Modernize legacy RecyclerView adapters (#694)

* Modernize legacy RecyclerView adapters

Introduces new adapters based on the SearchableRepositoryViewModel and
using androidx.recyclerview.selection for multiselection support.

The following positive effects in behavior are observable to end-users:

- Search and navigation actions are executed on IO threads.
- RecyclerViews are now animated during searches (but not navigations).
- Exact scroll position is restored when navigating back.
- The ActionBar title is updated with the current folder name.

The following negative effects may warrant attention:

- Support for the "always search from root" setting has been removed.
- Due to a limitation of the fast scroll dependency, using the scroller
  may result in unwanted multiselections. If this is not fixed in the
  library, native fast scroller capabilities could be used, but these
  are more limited in appearance and to not offer popups.

* Fix lint

* Fix FastScroller/SelectionTracker incompatibility

* Immediately react to settings changes

* List directory entries when search term is blank

* Use isEmpty() instead of == ""

* Replace adapter inheritance with builders and fix selection drags

* Remove dividers in password lists

* Run spotlessApply

* Use a more logical string in action mode

* Commonize and constify path bundle key

* Make lambda parameter name explicit

Signed-off-by: Harsh Shandilya <me@msfjarvis.dev>
Co-authored-by: Harsh Shandilya <me@msfjarvis.dev>

app/build.gradle

@@ -86,12 +86,13 @@ dependencies {
     implementation deps.androidx.documentfile
     implementation deps.androidx.fragment_ktx
     implementation deps.androidx.lifecycle_livedata_ktx
-    implementation deps.androidx.lifecycle_runtime_ktx
+    implementation deps.androidx.lifecycle_viewmodel_ktx
     implementation deps.androidx.local_broadcast_manager
     implementation deps.androidx.material
     implementation deps.androidx.preference
     implementation deps.androidx.swiperefreshlayout
-    implementation(deps.androidx.recycler_view)
+    implementation deps.androidx.recycler_view
+    implementation deps.androidx.recycler_view_selection
 
     implementation deps.kotlin.coroutines.android
     implementation deps.kotlin.coroutines.core

app/src/main/java/com/zeapo/pwdstore/PasswordFragment.kt

@@ -6,57 +6,43 @@ package com.zeapo.pwdstore
 
 import android.content.Context
 import android.content.Intent
-import android.content.SharedPreferences
 import android.os.Bundle
+import android.os.Parcelable
 import android.view.LayoutInflater
+import android.view.Menu
+import android.view.MenuItem
 import android.view.View
 import android.view.ViewGroup
-import androidx.appcompat.app.AppCompatActivity
+import androidx.appcompat.view.ActionMode
 import androidx.fragment.app.Fragment
-import androidx.preference.PreferenceManager
+import androidx.fragment.app.activityViewModels
-import androidx.recyclerview.widget.DividerItemDecoration
+import androidx.lifecycle.observe
 import androidx.recyclerview.widget.LinearLayoutManager
 import androidx.recyclerview.widget.RecyclerView
 import androidx.swiperefreshlayout.widget.SwipeRefreshLayout
 import com.google.android.material.floatingactionbutton.FloatingActionButton
 import com.google.android.material.snackbar.Snackbar
 import com.zeapo.pwdstore.git.GitActivity
-import com.zeapo.pwdstore.ui.adapters.PasswordRecyclerAdapter
+import com.zeapo.pwdstore.ui.OnOffItemAnimator
+import com.zeapo.pwdstore.ui.adapters.PasswordItemRecyclerAdapter
 import com.zeapo.pwdstore.utils.PasswordItem
 import com.zeapo.pwdstore.utils.PasswordRepository
-import com.zeapo.pwdstore.utils.PasswordRepository.Companion.getPasswords
-import com.zeapo.pwdstore.utils.PasswordRepository.Companion.getRepositoryDirectory
-import com.zeapo.pwdstore.utils.PasswordRepository.PasswordSortOrder.Companion.getSortOrder
 import java.io.File
 import java.util.Stack
 import me.zhanghai.android.fastscroll.FastScrollerBuilder
 
-/**
- * A fragment representing a list of Items.
- *
- * Large screen devices (such as tablets) are supported by replacing the ListView with a
- * GridView.
- *
- */
-
 class PasswordFragment : Fragment() {
-    // store the pass files list in a stack
+    private lateinit var recyclerAdapter: PasswordItemRecyclerAdapter
-    private var passListStack: Stack<ArrayList<PasswordItem>> = Stack()
-    private var pathStack: Stack<File> = Stack()
-    private var scrollPosition: Stack<Int> = Stack()
-    private lateinit var recyclerAdapter: PasswordRecyclerAdapter
     private lateinit var recyclerView: RecyclerView
     private lateinit var listener: OnFragmentInteractionListener
-    private lateinit var settings: SharedPreferences
     private lateinit var swipeRefresher: SwipeRefreshLayout
 
-    override fun onCreate(savedInstanceState: Bundle?) {
+    private var recyclerViewStateToRestore: Parcelable? = null
-        super.onCreate(savedInstanceState)
+    private var actionMode: ActionMode? = null
-        val path = requireNotNull(requireArguments().getString("Path"))
+
-        settings = PreferenceManager.getDefaultSharedPreferences(requireActivity())
+    private val model: SearchableRepositoryViewModel by activityViewModels()
-        recyclerAdapter = PasswordRecyclerAdapter((requireActivity() as PasswordStore),
+
-                listener, getPasswords(File(path), getRepositoryDirectory(requireContext()), sortOrder))
+    private fun requireStore() = requireActivity() as PasswordStore
-    }
 
     override fun onCreateView(
         inflater: LayoutInflater,
@@ -64,12 +50,28 @@ class PasswordFragment : Fragment() {
         savedInstanceState: Bundle?
     ): View? {
         val view = inflater.inflate(R.layout.password_recycler_view, container, false)
-        // use a linear layout manager
+        initializePasswordList(view)
-        val layoutManager = LinearLayoutManager(requireContext())
+        val fab = view.findViewById<FloatingActionButton>(R.id.fab)
-        swipeRefresher = view.findViewById(R.id.swipe_refresher)
+        fab.setOnClickListener {
+            toggleFabExpand(fab)
+        }
+        view.findViewById<FloatingActionButton>(R.id.create_folder).setOnClickListener {
+            requireStore().createFolder()
+            toggleFabExpand(fab)
+        }
+        view.findViewById<FloatingActionButton>(R.id.create_password).setOnClickListener {
+            requireStore().createPassword()
+            toggleFabExpand(fab)
+        }
+        return view
+    }
+
+    private fun initializePasswordList(rootView: View) {
+        swipeRefresher = rootView.findViewById(R.id.swipe_refresher)
         swipeRefresher.setOnRefreshListener {
             if (!PasswordRepository.isGitRepo()) {
-                Snackbar.make(view, getString(R.string.clone_git_repo), Snackbar.LENGTH_SHORT).show()
+                Snackbar.make(rootView, getString(R.string.clone_git_repo), Snackbar.LENGTH_SHORT)
+                    .show()
                 swipeRefresher.isRefreshing = false
             } else {
                 val intent = Intent(context, GitActivity::class.java)
@@ -77,30 +79,54 @@ class PasswordFragment : Fragment() {
                 startActivityForResult(intent, GitActivity.REQUEST_SYNC)
             }
         }
-        recyclerView = view.findViewById(R.id.pass_recycler)
+
-        recyclerView.layoutManager = layoutManager
+        recyclerAdapter = PasswordItemRecyclerAdapter()
-        // use divider
+            .onItemClicked { _, item ->
-        recyclerView.addItemDecoration(DividerItemDecoration(requireContext(), DividerItemDecoration.VERTICAL))
+                listener.onFragmentInteraction(item)
-        // Set the adapter
+            }
-        recyclerView.adapter = recyclerAdapter
+            .onSelectionChanged { selection ->
-        // Setup fast scroller
+                // In order to not interfere with drag selection, we disable the SwipeRefreshLayout
+                // once an item is selected.
+                swipeRefresher.isEnabled = selection.isEmpty
+
+                if (actionMode == null)
+                    actionMode = requireStore().startSupportActionMode(actionModeCallback)
+                        ?: return@onSelectionChanged
+
+                if (!selection.isEmpty) {
+                    actionMode!!.title = resources.getQuantityString(R.plurals.delete_title, selection.size(), selection.size())
+                    actionMode!!.invalidate()
+                } else {
+                    actionMode!!.finish()
+                }
+            }
+        recyclerView = rootView.findViewById(R.id.pass_recycler)
+        recyclerView.apply {
+            layoutManager = LinearLayoutManager(requireContext())
+            itemAnimator = OnOffItemAnimator()
+            adapter = recyclerAdapter
+        }
+
+        // FastScrollerBuilder.build() needs to be called *before* recyclerAdapter.makeSelectable(),
+        // as otherwise dragging the fast scroller will lead to items being selected.
+        // See https://github.com/zhanghai/AndroidFastScroll/issues/13
         FastScrollerBuilder(recyclerView).build()
-        val fab = view.findViewById<FloatingActionButton>(R.id.fab)
+        recyclerAdapter.makeSelectable(recyclerView)
-        fab.setOnClickListener {
-            toggleFabExpand(fab)
-        }
-
-        view.findViewById<FloatingActionButton>(R.id.create_folder).setOnClickListener {
-            (requireActivity() as PasswordStore).createFolder()
-            toggleFabExpand(fab)
-        }
-
-        view.findViewById<FloatingActionButton>(R.id.create_password).setOnClickListener {
-            (requireActivity() as PasswordStore).createPassword()
-            toggleFabExpand(fab)
-        }
         registerForContextMenu(recyclerView)
-        return view
+
+        val path = requireNotNull(requireArguments().getString(PasswordStore.REQUEST_ARG_PATH))
+        model.navigateTo(File(path), pushPreviousLocation = false)
+        model.searchResult.observe(this) { result ->
+            // Only run animations when the new list is filtered, i.e., the user submitted a search,
+            // and not on folder navigations since the latter leads to too many removal animations.
+            (recyclerView.itemAnimator as OnOffItemAnimator).isEnabled = result.isFiltered
+            recyclerAdapter.submitList(result.passwordItems) {
+                recyclerViewStateToRestore?.let {
+                    recyclerView.layoutManager!!.onRestoreInstanceState(it)
+                }
+                recyclerViewStateToRestore = null
+            }
+        }
     }
 
     private fun toggleFabExpand(fab: FloatingActionButton) = with(fab) {
@@ -109,30 +135,80 @@ class PasswordFragment : Fragment() {
         animate().rotationBy(if (isExpanded) -45f else 45f).setDuration(100).start()
     }
 
+    private val actionModeCallback = object : ActionMode.Callback {
+
+        // Called when the action mode is created; startActionMode() was called
+        override fun onCreateActionMode(mode: ActionMode, menu: Menu): Boolean {
+            // Inflate a menu resource providing context menu items
+            mode.menuInflater.inflate(R.menu.context_pass, menu)
+            // hide the fab
+            requireActivity().findViewById<View>(R.id.fab).visibility = View.GONE
+            return true
+        }
+
+        // Called each time the action mode is shown. Always called after onCreateActionMode, but
+        // may be called multiple times if the mode is invalidated.
+        override fun onPrepareActionMode(mode: ActionMode, menu: Menu): Boolean {
+            menu.findItem(R.id.menu_edit_password).isVisible =
+                recyclerAdapter.getSelectedItems(requireContext())
+                    .map { it.type == PasswordItem.TYPE_PASSWORD }
+                    .singleOrNull() == true
+            return true // Return false if nothing is done
+        }
+
+        // Called when the user selects a contextual menu item
+        override fun onActionItemClicked(mode: ActionMode, item: MenuItem): Boolean {
+            when (item.itemId) {
+                R.id.menu_delete_password -> {
+                    requireStore().deletePasswords(
+                        Stack<PasswordItem>().apply {
+                            recyclerAdapter.getSelectedItems(requireContext()).forEach { push(it) }
+                        }
+                    )
+                    mode.finish() // Action picked, so close the CAB
+                    return true
+                }
+                R.id.menu_edit_password -> {
+                    requireStore().editPassword(
+                        recyclerAdapter.getSelectedItems(requireContext()).first()
+                    )
+                    mode.finish()
+                    return true
+                }
+                R.id.menu_move_password -> {
+                    requireStore().movePasswords(recyclerAdapter.getSelectedItems(requireContext()))
+                    return false
+                }
+                else -> return false
+            }
+        }
+
+        // Called when the user exits the action mode
+        override fun onDestroyActionMode(mode: ActionMode) {
+            recyclerAdapter.requireSelectionTracker().clearSelection()
+            actionMode = null
+            // show the fab
+            requireActivity().findViewById<View>(R.id.fab).visibility = View.VISIBLE
+        }
+    }
+
     override fun onAttach(context: Context) {
         super.onAttach(context)
         try {
             listener = object : OnFragmentInteractionListener {
                 override fun onFragmentInteraction(item: PasswordItem) {
-                    if (item.type == PasswordItem.TYPE_CATEGORY) { // push the current password list (non filtered plz!)
+                    if (item.type == PasswordItem.TYPE_CATEGORY) {
-                        passListStack.push(
+                        requireStore().clearSearch()
-                                if (pathStack.isEmpty())
+                        model.navigateTo(
-                                    getPasswords(getRepositoryDirectory(context), sortOrder)
+                            item.file,
-                                else
+                            recyclerViewState = recyclerView.layoutManager!!.onSaveInstanceState()
-                                    getPasswords(pathStack.peek(), getRepositoryDirectory(context), sortOrder)
                         )
-                        // push the category were we're going
+                        requireStore().supportActionBar?.setDisplayHomeAsUpEnabled(true)
-                        pathStack.push(item.file)
-                        scrollPosition.push((recyclerView.layoutManager as LinearLayoutManager).findLastCompletelyVisibleItemPosition())
-                        recyclerView.scrollToPosition(0)
-                        recyclerAdapter.clear()
-                        recyclerAdapter.addAll(getPasswords(item.file, getRepositoryDirectory(context), sortOrder))
-                        (requireActivity() as AppCompatActivity).supportActionBar?.setDisplayHomeAsUpEnabled(true)
                     } else {
                         if (requireArguments().getBoolean("matchWith", false)) {
-                            (requireActivity() as PasswordStore).matchPasswordWithApp(item)
+                            requireStore().matchPasswordWithApp(item)
                         } else {
-                            (requireActivity() as PasswordStore).decryptPassword(item)
+                            requireStore().decryptPassword(item)
                         }
                     }
                 }
@@ -146,120 +222,27 @@ class PasswordFragment : Fragment() {
         swipeRefresher.isRefreshing = false
     }
 
-    /** clears the adapter content and sets it back to the root view  */
-    fun updateAdapter() {
-        passListStack.clear()
-        pathStack.clear()
-        scrollPosition.clear()
-        recyclerAdapter.clear()
-        recyclerAdapter.addAll(getPasswords(getRepositoryDirectory(requireContext()), sortOrder))
-        (requireActivity() as AppCompatActivity).supportActionBar?.setDisplayHomeAsUpEnabled(false)
-    }
-
-    /** refreshes the adapter with the latest opened category  */
-    fun refreshAdapter() {
-        recyclerAdapter.clear()
-        val currentDir = if (pathStack.isEmpty()) getRepositoryDirectory(requireContext()) else pathStack.peek()
-        recyclerAdapter.addAll(
-                if (pathStack.isEmpty())
-                    getPasswords(currentDir, sortOrder)
-                else
-                    getPasswords(currentDir, getRepositoryDirectory(requireContext()), sortOrder)
-        )
-    }
-
     /**
-     * filters the list adapter
+     * Returns true if the back press was handled by the [Fragment].
-     *
-     * @param filter the filter to apply
      */
-    fun filterAdapter(filter: String) {
+    fun onBackPressedInActivity(): Boolean {
-        if (filter.isEmpty()) {
+        if (!model.canNavigateBack)
-            refreshAdapter()
+            return false
-        } else {
+        // The RecyclerView state is restored when the asynchronous update operation on the
-            recursiveFilter(
+        // adapter is completed.
-                    filter,
+        recyclerViewStateToRestore = model.navigateBack()
-                    if (pathStack.isEmpty() ||
+        if (!model.canNavigateBack)
-                            settings.getBoolean("search_from_root", false))
+            requireStore().supportActionBar?.setDisplayHomeAsUpEnabled(false)
-                        null
+        return true
-                    else pathStack.peek())
-        }
     }
 
-    /**
+    val currentDir: File
-     * fuzzy matches the filter against the given string
+        get() = model.currentDir.value!!
-     *
-     * based on https://www.forrestthewoods.com/blog/reverse_engineering_sublime_texts_fuzzy_match/
-     *
-     * @param filter the filter to apply
-     * @param str the string to filter against
-     *
-     * @return true if the filter fuzzymatches the string
-     */
-    private fun fuzzyMatch(filter: String, str: String): Boolean {
-        var i = 0
-        var j = 0
-        while (i < filter.length && j < str.length) {
-            if (filter[i].isWhitespace() || filter[i].toLowerCase() == str[j].toLowerCase())
-                i++
-            j++
-        }
-        return i == filter.length
-    }
-
-    /**
-     * recursively filters a directory and extract all the matching items
-     *
-     * @param filter the filter to apply
-     * @param dir the directory to filter
-     */
-    private fun recursiveFilter(filter: String, dir: File?) { // on the root the pathStack is empty
-        val passwordItems = if (dir == null)
-            getPasswords(getRepositoryDirectory(requireContext()), sortOrder)
-        else
-            getPasswords(dir, getRepositoryDirectory(requireContext()), sortOrder)
-        val rec = settings.getBoolean("filter_recursively", true)
-        for (item in passwordItems) {
-            if (item.type == PasswordItem.TYPE_CATEGORY && rec) {
-                recursiveFilter(filter, item.file)
-            }
-            val matches = fuzzyMatch(filter, item.longName)
-            val inAdapter = recyclerAdapter.values.contains(item)
-            if (matches && !inAdapter) {
-                recyclerAdapter.add(item)
-            } else if (!matches && inAdapter) {
-                recyclerAdapter.remove(recyclerAdapter.values.indexOf(item))
-            }
-        }
-    }
-
-    /** Goes back one level back in the path  */
-    fun popBack() {
-        if (passListStack.isEmpty()) return
-        (recyclerView.layoutManager as LinearLayoutManager).scrollToPosition(scrollPosition.pop())
-        recyclerAdapter.clear()
-        recyclerAdapter.addAll(passListStack.pop())
-        pathStack.pop()
-    }
-
-    /**
-     * gets the current directory
-     *
-     * @return the current directory
-     */
-    val currentDir: File?
-        get() = if (pathStack.isEmpty()) getRepositoryDirectory(requireContext()) else pathStack.peek()
-
-    val isNotEmpty: Boolean
-        get() = !passListStack.isEmpty()
 
     fun dismissActionMode() {
-        recyclerAdapter.actionMode?.finish()
+        actionMode?.finish()
     }
 
-    private val sortOrder: PasswordRepository.PasswordSortOrder
-        get() = getSortOrder(settings)
-
     interface OnFragmentInteractionListener {
         fun onFragmentInteraction(item: PasswordItem)
     }

app/src/main/java/com/zeapo/pwdstore/PasswordStore.kt

@@ -22,6 +22,7 @@ import android.view.Menu
 import android.view.MenuItem
 import android.view.MenuItem.OnActionExpandListener
 import android.view.View
+import androidx.activity.viewModels
 import androidx.appcompat.app.AppCompatActivity
 import androidx.appcompat.widget.AppCompatTextView
 import androidx.appcompat.widget.SearchView
@@ -29,6 +30,8 @@ import androidx.appcompat.widget.SearchView.OnQueryTextListener
 import androidx.core.app.ActivityCompat
 import androidx.core.content.ContextCompat
 import androidx.fragment.app.FragmentManager
+import androidx.lifecycle.ViewModelProvider
+import androidx.lifecycle.observe
 import androidx.preference.PreferenceManager
 import com.google.android.material.dialog.MaterialAlertDialogBuilder
 import com.google.android.material.snackbar.Snackbar
@@ -38,7 +41,6 @@ import com.zeapo.pwdstore.crypto.PgpActivity.Companion.getLongName
 import com.zeapo.pwdstore.git.GitActivity
 import com.zeapo.pwdstore.git.GitAsyncTask
 import com.zeapo.pwdstore.git.GitOperation
-import com.zeapo.pwdstore.ui.adapters.PasswordRecyclerAdapter
 import com.zeapo.pwdstore.ui.dialogs.FolderCreationDialogFragment
 import com.zeapo.pwdstore.utils.PasswordItem
 import com.zeapo.pwdstore.utils.PasswordRepository
@@ -52,6 +54,7 @@ import com.zeapo.pwdstore.utils.PasswordRepository.Companion.isInitialized
 import com.zeapo.pwdstore.utils.PasswordRepository.PasswordSortOrder.Companion.getSortOrder
 import java.io.File
 import java.lang.Character.UnicodeBlock
+import java.util.Stack
 import org.apache.commons.io.FileUtils
 import org.apache.commons.io.FilenameUtils
 import org.eclipse.jgit.api.Git
@@ -68,6 +71,10 @@ class PasswordStore : AppCompatActivity() {
     private var plist: PasswordFragment? = null
     private var shortcutManager: ShortcutManager? = null
 
+    private val model: SearchableRepositoryViewModel by viewModels {
+        ViewModelProvider.AndroidViewModelFactory(application)
+    }
+
     override fun onKeyDown(keyCode: Int, event: KeyEvent): Boolean {
         // open search view on search key, or Ctr+F
         if ((keyCode == KeyEvent.KEYCODE_SEARCH || keyCode == KeyEvent.KEYCODE_F && event.isCtrlPressed) &&
@@ -106,6 +113,16 @@ class PasswordStore : AppCompatActivity() {
         }
         super.onCreate(savedInstance)
         setContentView(R.layout.activity_pwdstore)
+
+        model.currentDir.observe(this) { dir ->
+            val basePath = getRepositoryDirectory(applicationContext).absoluteFile
+            supportActionBar!!.apply {
+                if (dir != basePath)
+                    title = dir.name
+                else
+                    setTitle(R.string.app_name)
+            }
+        }
     }
 
     public override fun onResume() {
@@ -165,19 +182,26 @@ class PasswordStore : AppCompatActivity() {
     }
 
     override fun onPrepareOptionsMenu(menu: Menu): Boolean {
-        // Inflate the menu; this adds items to the action bar if it is present.
         searchItem = menu.findItem(R.id.action_search)
         searchView = searchItem.actionView as SearchView
         searchView.setOnQueryTextListener(
                 object : OnQueryTextListener {
                     override fun onQueryTextSubmit(s: String): Boolean {
-                        filterListAdapter(s)
                         searchView.clearFocus()
                         return true
                     }
 
                     override fun onQueryTextChange(s: String): Boolean {
-                        filterListAdapter(s)
+                        val filter = s.trim()
+                        // List the contents of the current directory if the user enters a blank
+                        // search term.
+                        if (filter.isEmpty())
+                            model.navigateTo(
+                                newDirectory = model.currentDir.value!!,
+                                pushPreviousLocation = false
+                            )
+                        else
+                            model.search(filter)
                         return true
                     }
                 })
@@ -187,7 +211,7 @@ class PasswordStore : AppCompatActivity() {
         searchItem.setOnActionExpandListener(
                 object : OnActionExpandListener {
                     override fun onMenuItemActionCollapse(item: MenuItem): Boolean {
-                        refreshListAdapter()
+                        refreshPasswordList()
                         return true
                     }
 
@@ -251,7 +275,7 @@ class PasswordStore : AppCompatActivity() {
                 return true
             }
             R.id.refresh -> {
-                updateListAdapter()
+                refreshPasswordList()
                 return true
             }
             android.R.id.home -> onBackPressed()
@@ -266,6 +290,10 @@ class PasswordStore : AppCompatActivity() {
         super.onDestroy()
     }
 
+    fun clearSearch() {
+        searchItem.collapseActionView()
+    }
+
     fun openSettings(view: View?) {
         val intent: Intent
         try {
@@ -354,7 +382,7 @@ class PasswordStore : AppCompatActivity() {
                 settings.edit().putBoolean("repo_changed", false).apply()
                 plist = PasswordFragment()
                 val args = Bundle()
-                args.putString("Path", getRepositoryDirectory(applicationContext).absolutePath)
+                args.putString(REQUEST_ARG_PATH, getRepositoryDirectory(applicationContext).absolutePath)
 
                 // if the activity was started from the autofill settings, the
                 // intent is to match a clicked pwd with app. pass this to fragment
@@ -378,15 +406,9 @@ class PasswordStore : AppCompatActivity() {
     }
 
     override fun onBackPressed() {
-        if (null != plist && plist!!.isNotEmpty) {
+        if (plist?.onBackPressedInActivity() != true)
-            plist!!.popBack()
-        } else {
             super.onBackPressed()
     }
-        if (null != plist && !plist!!.isNotEmpty) {
-            supportActionBar!!.setDisplayHomeAsUpEnabled(false)
-        }
-    }
 
     private fun getRelativePath(fullPath: String, repositoryPath: String): String {
         return fullPath.replace(repositoryPath, "").replace("/+".toRegex(), "/")
@@ -450,7 +472,7 @@ class PasswordStore : AppCompatActivity() {
         val intent = Intent(this, PgpActivity::class.java)
         intent.putExtra("NAME", item.toString())
         intent.putExtra("FILE_PATH", item.file.absolutePath)
-        intent.putExtra("PARENT_PATH", currentDir!!.absolutePath)
+        intent.putExtra("PARENT_PATH", item.file.parentFile.absolutePath)
         intent.putExtra("REPO_PATH", getRepositoryDirectory(applicationContext).absolutePath)
         intent.putExtra("OPERATION", "EDIT")
         startActivityForResult(intent, REQUEST_CODE_EDIT)
@@ -481,7 +503,7 @@ class PasswordStore : AppCompatActivity() {
     fun createPassword() {
         if (!validateState()) return
         val currentDir = currentDir
-        Timber.tag(TAG).i("Adding file to : ${currentDir!!.absolutePath}")
+        Timber.tag(TAG).i("Adding file to : ${currentDir.absolutePath}")
         val intent = Intent(this, PgpActivity::class.java)
         intent.putExtra("FILE_PATH", currentDir.absolutePath)
         intent.putExtra("REPO_PATH", getRepositoryDirectory(applicationContext).absolutePath)
@@ -491,17 +513,16 @@ class PasswordStore : AppCompatActivity() {
 
     fun createFolder() {
         if (!validateState()) return
-        FolderCreationDialogFragment.newInstance(currentDir!!.path).show(supportFragmentManager, null)
+        FolderCreationDialogFragment.newInstance(currentDir.path).show(supportFragmentManager, null)
     }
 
     // deletes passwords in order from top to bottom
-    fun deletePasswords(adapter: PasswordRecyclerAdapter, selectedItems: MutableSet<Int>) {
+    fun deletePasswords(selectedItems: Stack<PasswordItem>) {
-        val it: MutableIterator<*> = selectedItems.iterator()
+        if (selectedItems.isEmpty()) {
-        if (!it.hasNext()) {
+            refreshPasswordList()
             return
         }
-        val position = it.next() as Int
+        val item = selectedItems.pop()
-        val item = adapter.values[position]
         MaterialAlertDialogBuilder(this)
                 .setMessage(resources.getString(R.string.delete_dialog_text, item.longName))
                 .setPositiveButton(resources.getString(R.string.dialog_yes)) { _, _ ->
@@ -512,20 +533,16 @@ class PasswordStore : AppCompatActivity() {
                     }
                     AutofillMatcher.updateMatches(applicationContext, delete = filesToDelete)
                     item.file.deleteRecursively()
-                    adapter.remove(position)
-                    it.remove()
-                    adapter.updateSelectedItems(position, selectedItems)
                     commitChange(resources.getString(R.string.git_commit_remove_text, item.longName))
-                    deletePasswords(adapter, selectedItems)
+                    deletePasswords(selectedItems)
                 }
                 .setNegativeButton(this.resources.getString(R.string.dialog_no)) { _, _ ->
-                    it.remove()
+                    deletePasswords(selectedItems)
-                    deletePasswords(adapter, selectedItems)
                 }
                 .show()
     }
 
-    fun movePasswords(values: ArrayList<PasswordItem>) {
+    fun movePasswords(values: List<PasswordItem>) {
         val intent = Intent(this, SelectFolderActivity::class.java)
         val fileLocations = ArrayList<String>()
         for ((_, _, _, file) in values) {
@@ -536,21 +553,28 @@ class PasswordStore : AppCompatActivity() {
         startActivityForResult(intent, REQUEST_CODE_SELECT_FOLDER)
     }
 
-    /** clears adapter's content and updates it with a fresh list of passwords from the root  */
+    /**
-    fun updateListAdapter() {
+     * Resets navigation to the repository root and refreshes the password list accordingly.
-        plist?.updateAdapter()
+     *
+     * Use this rather than [refreshPasswordList] after major file system operations that may remove
+     * the current directory and thus require a full reset of the navigation stack.
+     */
+    fun resetPasswordList() {
+        model.reset()
+        supportActionBar!!.setDisplayHomeAsUpEnabled(false)
     }
 
-    /** Updates the adapter with the current view of passwords  */
+    /**
-    private fun refreshListAdapter() {
+     * Refreshes the password list by re-executing the last navigation or search action.
-        plist?.refreshAdapter()
+     *
+     * Use this rather than [resetPasswordList] after file system operations limited to the current
+     * folder since it preserves the scroll position and navigation stack.
+     */
+    fun refreshPasswordList() {
+        model.forceRefresh()
     }
 
-    private fun filterListAdapter(filter: String) {
+    private val currentDir: File
-        plist?.filterAdapter(filter)
-    }
-
-    private val currentDir: File?
         get() = plist?.currentDir ?: getRepositoryDirectory(applicationContext)
 
     private fun commitChange(message: String) {
@@ -578,14 +602,14 @@ class PasswordStore : AppCompatActivity() {
                                             data.extras!!.getString("LONG_NAME")))
                         }
                     }
-                    refreshListAdapter()
+                    refreshPasswordList()
                 }
                 REQUEST_CODE_ENCRYPT -> {
                     commitChange(this.resources
                             .getString(
                                     R.string.git_commit_add_text,
                                     data!!.extras!!.getString("LONG_NAME")))
-                    refreshListAdapter()
+                    refreshPasswordList()
                 }
                 REQUEST_CODE_EDIT -> {
                     commitChange(
@@ -593,10 +617,10 @@ class PasswordStore : AppCompatActivity() {
                                     .getString(
                                             R.string.git_commit_edit_text,
                                             data!!.extras!!.getString("LONG_NAME")))
-                    refreshListAdapter()
+                    refreshPasswordList()
                 }
                 GitActivity.REQUEST_INIT, NEW_REPO_BUTTON -> initializeRepositoryInfo()
-                GitActivity.REQUEST_SYNC, GitActivity.REQUEST_PULL -> updateListAdapter()
+                GitActivity.REQUEST_SYNC, GitActivity.REQUEST_PULL -> resetPasswordList()
                 HOME -> checkLocalRepository()
                 // duplicate code
                 CLONE_REPO_BUTTON -> {
@@ -677,7 +701,7 @@ class PasswordStore : AppCompatActivity() {
                                             destinationLongName))
                         }
                     }
-                    updateListAdapter()
+                    resetPasswordList()
                     if (plist != null) {
                         plist!!.dismissActionMode()
                     }
@@ -760,6 +784,7 @@ class PasswordStore : AppCompatActivity() {
         const val REQUEST_CODE_GET_KEY_IDS = 9915
         const val REQUEST_CODE_EDIT = 9916
         const val REQUEST_CODE_SELECT_FOLDER = 9917
+        const val REQUEST_ARG_PATH = "PATH"
         private val TAG = PasswordStore::class.java.name
         private const val CLONE_REPO_BUTTON = 401
         private const val NEW_REPO_BUTTON = 402

app/src/main/java/com/zeapo/pwdstore/SearchableRepositoryViewModel.kt

@@ -5,14 +5,23 @@
 package com.zeapo.pwdstore
 
 import android.app.Application
+import android.content.Context
+import android.os.Parcelable
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
 import androidx.lifecycle.AndroidViewModel
+import androidx.lifecycle.LiveData
 import androidx.lifecycle.MutableLiveData
 import androidx.lifecycle.asFlow
 import androidx.lifecycle.asLiveData
 import androidx.preference.PreferenceManager
+import androidx.recyclerview.selection.ItemDetailsLookup
+import androidx.recyclerview.selection.ItemKeyProvider
+import androidx.recyclerview.selection.Selection
+import androidx.recyclerview.selection.SelectionPredicates
+import androidx.recyclerview.selection.SelectionTracker
+import androidx.recyclerview.selection.StorageStrategy
 import androidx.recyclerview.widget.DiffUtil
 import androidx.recyclerview.widget.ListAdapter
 import androidx.recyclerview.widget.RecyclerView
@@ -22,6 +31,8 @@ import com.zeapo.pwdstore.utils.PasswordItem
 import com.zeapo.pwdstore.utils.PasswordRepository
 import java.io.File
 import java.text.Collator
+import java.util.Locale
+import java.util.Stack
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.ExperimentalCoroutinesApi
 import kotlinx.coroutines.FlowPreview
@@ -32,8 +43,10 @@ import kotlinx.coroutines.flow.emptyFlow
 import kotlinx.coroutines.flow.filter
 import kotlinx.coroutines.flow.map
 import kotlinx.coroutines.flow.mapLatest
+import kotlinx.coroutines.flow.merge
 import kotlinx.coroutines.flow.toList
 import kotlinx.coroutines.yield
+import me.zhanghai.android.fastscroll.PopupTextProvider
 
 private fun File.toPasswordItem(root: File) = if (isFile)
     PasswordItem.newPassword(name, this, root)
@@ -89,8 +102,11 @@ private fun PasswordItem.Companion.makeComparator(
         .then(compareBy(CaseInsensitiveComparator) { directoryStructure.getUsernameFor(it.file) })
 }
 
+val PasswordItem.stableId: String
+    get() = file.absolutePath
+
 enum class FilterMode {
-    ListOnly,
+    NoFilter,
     StrictDomain,
     Fuzzy
 }
@@ -100,65 +116,109 @@ enum class SearchMode {
     InCurrentDirectoryOnly
 }
 
-private data class SearchAction(
+enum class ListMode {
-    val currentDir: File,
+    FilesOnly,
-    val filter: String,
+    DirectoriesOnly,
-    val filterMode: FilterMode,
+    AllEntries
-    val searchMode: SearchMode,
+}
-    val listFilesOnly: Boolean
-)
 
 @ExperimentalCoroutinesApi
 @FlowPreview
 class SearchableRepositoryViewModel(application: Application) : AndroidViewModel(application) {
-    private val root = PasswordRepository.getRepositoryDirectory(application)
+
+    private var _updateCounter = 0
+    private val updateCounter: Int
+        get() = _updateCounter
+
+    private fun forceUpdateOnNextSearchAction() {
+        _updateCounter++
+    }
+
+    private val root
+        get() = PasswordRepository.getRepositoryDirectory(getApplication())
     private val settings = PreferenceManager.getDefaultSharedPreferences(getApplication())
-    private val showHiddenDirs = settings.getBoolean("show_hidden_folders", false)
+    private val showHiddenDirs
-    private val searchFromRoot = settings.getBoolean("search_from_root", false)
+        get() = settings.getBoolean("show_hidden_folders", false)
-    private val defaultSearchMode = if (settings.getBoolean("filter_recursively", true)) {
+    private val defaultSearchMode
+        get() = if (settings.getBoolean("filter_recursively", true)) {
         SearchMode.RecursivelyInSubdirectories
     } else {
         SearchMode.InCurrentDirectoryOnly
     }
 
-    private val typeSortOrder = PasswordRepository.PasswordSortOrder.getSortOrder(settings)
+    private val typeSortOrder
-    private val directoryStructure = AutofillPreferences.directoryStructure(application)
+        get() = PasswordRepository.PasswordSortOrder.getSortOrder(settings)
-    private val itemComparator = PasswordItem.makeComparator(typeSortOrder, directoryStructure)
+    private val directoryStructure
+        get() = AutofillPreferences.directoryStructure(getApplication())
+    private val itemComparator
+        get() = PasswordItem.makeComparator(typeSortOrder, directoryStructure)
+
+    private data class SearchAction(
+        val baseDirectory: File,
+        val filter: String,
+        val filterMode: FilterMode,
+        val searchMode: SearchMode,
+        val listMode: ListMode,
+        // This counter can be increased to force a reexecution of the search action even if all
+        // other arguments are left unchanged.
+        val updateCounter: Int
+    )
+
+    private fun makeSearchAction(
+        baseDirectory: File,
+        filter: String,
+        filterMode: FilterMode,
+        searchMode: SearchMode,
+        listMode: ListMode
+    ): SearchAction {
+        return SearchAction(
+            baseDirectory = baseDirectory,
+            filter = filter,
+            filterMode = filterMode,
+            searchMode = searchMode,
+            listMode = listMode,
+            updateCounter = updateCounter
+        )
+    }
+
+    private fun updateSearchAction(action: SearchAction) =
+        action.copy(updateCounter = updateCounter)
 
     private val searchAction = MutableLiveData(
-        SearchAction(
+        makeSearchAction(
-            currentDir = root,
+            baseDirectory = root,
             filter = "",
-            filterMode = FilterMode.ListOnly,
+            filterMode = FilterMode.NoFilter,
             searchMode = SearchMode.InCurrentDirectoryOnly,
-            listFilesOnly = true
+            listMode = ListMode.AllEntries
         )
     )
-    private val searchActionFlow = searchAction.asFlow()
+    private val searchActionFlow = searchAction.asFlow().distinctUntilChanged()
-        .map { it.copy(filter = it.filter.trim()) }
-        .distinctUntilChanged()
 
-    private val passwordItemsFlow = searchActionFlow
+    data class SearchResult(val passwordItems: List<PasswordItem>, val isFiltered: Boolean)
+
+    private val newResultFlow = searchActionFlow
         .mapLatest { searchAction ->
-            val dirToSearch =
-                if (searchFromRoot && searchAction.filterMode != FilterMode.ListOnly) root else searchAction.currentDir
             val listResultFlow = when (searchAction.searchMode) {
-                SearchMode.RecursivelyInSubdirectories -> listFilesRecursively(dirToSearch)
+                SearchMode.RecursivelyInSubdirectories -> listFilesRecursively(searchAction.baseDirectory)
-                SearchMode.InCurrentDirectoryOnly -> listFiles(dirToSearch)
+                SearchMode.InCurrentDirectoryOnly -> listFiles(searchAction.baseDirectory)
+            }
+            val prefilteredResultFlow = when (searchAction.listMode) {
+                ListMode.FilesOnly -> listResultFlow.filter { it.isFile }
+                ListMode.DirectoriesOnly -> listResultFlow.filter { it.isDirectory }
+                ListMode.AllEntries -> listResultFlow
             }
-            val prefilteredResultFlow =
-                if (searchAction.listFilesOnly) listResultFlow.filter { it.isFile } else listResultFlow
             val filterModeToUse =
-                if (searchAction.filter == "") FilterMode.ListOnly else searchAction.filterMode
+                if (searchAction.filter == "") FilterMode.NoFilter else searchAction.filterMode
-            when (filterModeToUse) {
+            val passwordList = when (filterModeToUse) {
-                FilterMode.ListOnly -> {
+                FilterMode.NoFilter -> {
                     prefilteredResultFlow
                         .map { it.toPasswordItem(root) }
                         .toList()
                         .sortedWith(itemComparator)
                 }
                 FilterMode.StrictDomain -> {
-                    check(searchAction.listFilesOnly) { "Searches with StrictDomain search mode can only list files" }
+                    check(searchAction.listMode == ListMode.FilesOnly) { "Searches with StrictDomain search mode can only list files" }
                     prefilteredResultFlow
                         .filter { file ->
                             val toMatch =
@@ -190,39 +250,7 @@ class SearchableRepositoryViewModel(application: Application) : AndroidViewModel
                         .map { it.second }
                 }
             }
-        }
+            SearchResult(passwordList, isFiltered = searchAction.filterMode != FilterMode.NoFilter)
-
-    val passwordItemsList = passwordItemsFlow.asLiveData(Dispatchers.IO)
-
-    fun list(currentDir: File) {
-        require(currentDir.isDirectory) { "Can only list files in a directory" }
-        searchAction.postValue(
-            SearchAction(
-                filter = "",
-                currentDir = currentDir,
-                filterMode = FilterMode.ListOnly,
-                searchMode = SearchMode.InCurrentDirectoryOnly,
-                listFilesOnly = false
-            )
-        )
-    }
-
-    fun search(
-        filter: String,
-        currentDir: File? = null,
-        filterMode: FilterMode = FilterMode.Fuzzy,
-        searchMode: SearchMode? = null,
-        listFilesOnly: Boolean = false
-    ) {
-        require(currentDir?.isDirectory != false) { "Can only search in a directory" }
-        val action = SearchAction(
-            filter = filter.trim(),
-            currentDir = currentDir ?: searchAction.value!!.currentDir,
-            filterMode = filterMode,
-            searchMode = searchMode ?: defaultSearchMode,
-            listFilesOnly = listFilesOnly
-        )
-        searchAction.postValue(action)
         }
 
     private fun shouldTake(file: File) = with(file) {
@@ -247,6 +275,114 @@ class SearchableRepositoryViewModel(application: Application) : AndroidViewModel
             }
             .filter { file -> shouldTake(file) }
     }
+
+    private val cachedResult = MutableLiveData<SearchResult>()
+    val searchResult =
+        listOf(newResultFlow, cachedResult.asFlow()).merge().asLiveData(Dispatchers.IO)
+
+    private val _currentDir = MutableLiveData(root)
+    val currentDir = _currentDir as LiveData<File>
+
+    data class NavigationStackEntry(
+        val dir: File,
+        val items: List<PasswordItem>?,
+        val recyclerViewState: Parcelable?
+    )
+
+    private val navigationStack = Stack<NavigationStackEntry>()
+
+    fun navigateTo(
+        newDirectory: File = root,
+        listMode: ListMode = ListMode.AllEntries,
+        recyclerViewState: Parcelable? = null,
+        pushPreviousLocation: Boolean = true
+    ) {
+        require(newDirectory.isDirectory) { "Can only navigate to a directory" }
+        if (pushPreviousLocation) {
+            // We cache the current list entries only if the current list has not been filtered,
+            // otherwise it will be regenerated when moving back.
+            if (searchAction.value?.filterMode == FilterMode.NoFilter) {
+                navigationStack.push(
+                    NavigationStackEntry(
+                        _currentDir.value!!,
+                        searchResult.value?.passwordItems,
+                        recyclerViewState
+                    )
+                )
+            } else {
+                navigationStack.push(
+                    NavigationStackEntry(
+                        _currentDir.value!!,
+                        null,
+                        recyclerViewState
+                    )
+                )
+            }
+        }
+        searchAction.postValue(
+            makeSearchAction(
+                filter = "",
+                baseDirectory = newDirectory,
+                filterMode = FilterMode.NoFilter,
+                searchMode = SearchMode.InCurrentDirectoryOnly,
+                listMode = listMode
+            )
+        )
+        _currentDir.postValue(newDirectory)
+    }
+
+    val canNavigateBack
+        get() = navigationStack.isNotEmpty()
+
+    /**
+     * Navigate back to the last location on the [navigationStack] using a cached list of entries
+     * if possible.
+     *
+     * Returns the old RecyclerView's LinearLayoutManager state as a [Parcelable] if it was cached.
+     */
+    fun navigateBack(): Parcelable? {
+        if (!canNavigateBack) return null
+        val (oldDir, oldPasswordItems, oldRecyclerViewState) = navigationStack.pop()
+        return if (oldPasswordItems != null) {
+            // We cached the contents of oldDir and restore them directly without file operations.
+            cachedResult.postValue(SearchResult(oldPasswordItems, isFiltered = false))
+            _currentDir.postValue(oldDir)
+            oldRecyclerViewState
+        } else {
+            navigateTo(oldDir, pushPreviousLocation = false)
+            null
+        }
+    }
+
+    fun reset() {
+        navigationStack.clear()
+        forceUpdateOnNextSearchAction()
+        navigateTo(pushPreviousLocation = false)
+    }
+
+    fun search(
+        filter: String,
+        baseDirectory: File? = null,
+        filterMode: FilterMode = FilterMode.Fuzzy,
+        searchMode: SearchMode? = null,
+        listMode: ListMode = ListMode.AllEntries
+    ) {
+        require(baseDirectory?.isDirectory != false) { "Can only search in a directory" }
+        searchAction.postValue(
+            makeSearchAction(
+                filter = filter,
+                baseDirectory = baseDirectory ?: _currentDir.value!!,
+                filterMode = filterMode,
+                searchMode = searchMode ?: defaultSearchMode,
+                listMode = listMode
+            )
+        )
+    }
+
+    fun forceRefresh() {
+        forceUpdateOnNextSearchAction()
+        searchAction.postValue(updateSearchAction(searchAction.value!!))
+    }
 }
 
 private object PasswordItemDiffCallback : DiffUtil.ItemCallback<PasswordItem>() {
@@ -256,19 +392,85 @@ private object PasswordItemDiffCallback : DiffUtil.ItemCallback<PasswordItem>()
     override fun areContentsTheSame(oldItem: PasswordItem, newItem: PasswordItem) = oldItem == newItem
 }
 
-class DelegatedSearchableRepositoryAdapter<T : RecyclerView.ViewHolder>(
+open class SearchableRepositoryAdapter<T : RecyclerView.ViewHolder>(
     private val layoutRes: Int,
     private val viewHolderCreator: (view: View) -> T,
     private val viewHolderBinder: T.(item: PasswordItem) -> Unit
-) : ListAdapter<PasswordItem, T>(PasswordItemDiffCallback) {
+) : ListAdapter<PasswordItem, T>(PasswordItemDiffCallback), PopupTextProvider {
 
-    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): T {
+    fun <T : ItemDetailsLookup<String>> makeSelectable(
+        recyclerView: RecyclerView,
+        itemDetailsLookupCreator: (recyclerView: RecyclerView) -> T
+    ) {
+        selectionTracker = SelectionTracker.Builder(
+            "SearchableRepositoryAdapter",
+            recyclerView,
+            itemKeyProvider,
+            itemDetailsLookupCreator(recyclerView),
+            StorageStrategy.createStringStorage()
+        ).withSelectionPredicate(SelectionPredicates.createSelectAnything()).build().apply {
+            addObserver(object : SelectionTracker.SelectionObserver<String>() {
+                override fun onSelectionChanged() {
+                    this@SearchableRepositoryAdapter.onSelectionChangedListener?.invoke(
+                        requireSelectionTracker().selection
+                    )
+                }
+            })
+        }
+    }
+
+    private var onItemClickedListener: ((holder: T, item: PasswordItem) -> Unit)? = null
+    open fun onItemClicked(listener: (holder: T, item: PasswordItem) -> Unit): SearchableRepositoryAdapter<T> {
+        check(onItemClickedListener == null) { "Only a single listener can be registered for onItemClicked" }
+        onItemClickedListener = listener
+        return this
+    }
+
+    private var onSelectionChangedListener: ((selection: Selection<String>) -> Unit)? = null
+    open fun onSelectionChanged(listener: (selection: Selection<String>) -> Unit): SearchableRepositoryAdapter<T> {
+        check(onSelectionChangedListener == null) { "Only a single listener can be registered for onSelectionChanged" }
+        onSelectionChangedListener = listener
+        return this
+    }
+
+    private val itemKeyProvider = object : ItemKeyProvider<String>(SCOPE_MAPPED) {
+        override fun getKey(position: Int) = getItem(position).stableId
+
+        override fun getPosition(key: String) =
+            (0 until itemCount).firstOrNull { getItem(it).stableId == key }
+                ?: RecyclerView.NO_POSITION
+    }
+
+    private var selectionTracker: SelectionTracker<String>? = null
+    fun requireSelectionTracker() = selectionTracker!!
+
+    private val selectedFiles
+        get() = requireSelectionTracker().selection.map { File(it) }
+    fun getSelectedItems(context: Context): List<PasswordItem> {
+        val root = PasswordRepository.getRepositoryDirectory(context)
+        return selectedFiles.map { it.toPasswordItem(root) }
+    }
+
+    final override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): T {
         val view = LayoutInflater.from(parent.context)
             .inflate(layoutRes, parent, false)
         return viewHolderCreator(view)
     }
 
-    override fun onBindViewHolder(holder: T, position: Int) {
+    final override fun onBindViewHolder(holder: T, position: Int) {
-        viewHolderBinder.invoke(holder, getItem(position))
+        val item = getItem(position)
+        holder.apply {
+            viewHolderBinder.invoke(this, item)
+            selectionTracker?.let { itemView.isSelected = it.isSelected(item.stableId) }
+            itemView.setOnClickListener {
+                // Do not emit custom click events while the user is selecting items.
+                if (selectionTracker?.hasSelection() != true)
+                    onItemClickedListener?.invoke(holder, item)
+            }
+        }
+    }
+
+    final override fun getPopupText(position: Int): String {
+        return getItem(position).name[0].toString().toUpperCase(Locale.getDefault())
     }
 }

app/src/main/java/com/zeapo/pwdstore/SelectFolderActivity.kt

@@ -27,7 +27,7 @@ class SelectFolderActivity : AppCompatActivity() {
 
         passwordList = SelectFolderFragment()
         val args = Bundle()
-        args.putString("Path", PasswordRepository.getRepositoryDirectory(applicationContext).absolutePath)
+        args.putString(PasswordStore.REQUEST_ARG_PATH, PasswordRepository.getRepositoryDirectory(applicationContext).absolutePath)
 
         passwordList.arguments = args
 
@@ -58,7 +58,7 @@ class SelectFolderActivity : AppCompatActivity() {
     }
 
     private fun selectFolder() {
-        intent.putExtra("SELECTED_FOLDER_PATH", passwordList.currentDir?.absolutePath)
+        intent.putExtra("SELECTED_FOLDER_PATH", passwordList.currentDir.absolutePath)
         setResult(Activity.RESULT_OK, intent)
         finish()
     }

app/src/main/java/com/zeapo/pwdstore/SelectFolderFragment.kt

@@ -11,40 +11,22 @@ import android.view.View
 import android.view.ViewGroup
 import androidx.appcompat.app.AppCompatActivity
 import androidx.fragment.app.Fragment
-import androidx.preference.PreferenceManager
+import androidx.fragment.app.activityViewModels
-import androidx.recyclerview.widget.DividerItemDecoration
+import androidx.lifecycle.observe
 import androidx.recyclerview.widget.LinearLayoutManager
 import androidx.recyclerview.widget.RecyclerView
 import com.google.android.material.floatingactionbutton.FloatingActionButton
-import com.zeapo.pwdstore.ui.adapters.FolderRecyclerAdapter
+import com.zeapo.pwdstore.ui.adapters.PasswordItemRecyclerAdapter
 import com.zeapo.pwdstore.utils.PasswordItem
-import com.zeapo.pwdstore.utils.PasswordRepository
-import com.zeapo.pwdstore.utils.PasswordRepository.Companion.getPasswords
-import com.zeapo.pwdstore.utils.PasswordRepository.Companion.getRepositoryDirectory
-import com.zeapo.pwdstore.utils.PasswordRepository.PasswordSortOrder.Companion.getSortOrder
 import java.io.File
-import java.util.Stack
+import me.zhanghai.android.fastscroll.FastScrollerBuilder
-
-/**
- * A fragment representing a list of Items.
- *
- * Large screen devices (such as tablets) are supported by replacing the ListView with a
- * GridView.
- *
- */
 
 class SelectFolderFragment : Fragment() {
-    // store the pass files list in a stack
+    private lateinit var recyclerAdapter: PasswordItemRecyclerAdapter
-    private var pathStack: Stack<File> = Stack()
-    private lateinit var recyclerAdapter: FolderRecyclerAdapter
     private lateinit var recyclerView: RecyclerView
     private lateinit var listener: OnFragmentInteractionListener
 
-    override fun onCreate(savedInstanceState: Bundle?) {
+    private val model: SearchableRepositoryViewModel by activityViewModels()
-        super.onCreate(savedInstanceState)
-        val path = requireNotNull(requireArguments().getString("Path"))
-        recyclerAdapter = FolderRecyclerAdapter(listener, getPasswords(File(path), getRepositoryDirectory(requireActivity()), sortOrder))
-    }
 
     override fun onCreateView(
         inflater: LayoutInflater,
@@ -52,35 +34,41 @@ class SelectFolderFragment : Fragment() {
         savedInstanceState: Bundle?
     ): View? {
         val view = inflater.inflate(R.layout.password_recycler_view, container, false)
-        // use a linear layout manager
+        initializePasswordList(view)
-        recyclerView = view.findViewById(R.id.pass_recycler)
-        recyclerView.layoutManager = LinearLayoutManager(requireContext())
-        // use divider
-        recyclerView.addItemDecoration(
-                DividerItemDecoration(requireContext(), DividerItemDecoration.VERTICAL))
-        // Set the adapter
-        recyclerView.adapter = recyclerAdapter
         val fab: FloatingActionButton = view.findViewById(R.id.fab)
         fab.hide()
-        registerForContextMenu(recyclerView)
         return view
     }
 
+    private fun initializePasswordList(rootView: View) {
+        recyclerAdapter = PasswordItemRecyclerAdapter()
+            .onItemClicked { _, item ->
+                listener.onFragmentInteraction(item)
+            }
+        recyclerView = rootView.findViewById(R.id.pass_recycler)
+        recyclerView.apply {
+            layoutManager = LinearLayoutManager(requireContext())
+            itemAnimator = null
+            adapter = recyclerAdapter
+        }
+
+        FastScrollerBuilder(recyclerView).build()
+        registerForContextMenu(recyclerView)
+
+        val path = requireNotNull(requireArguments().getString(PasswordStore.REQUEST_ARG_PATH))
+        model.navigateTo(File(path), listMode = ListMode.DirectoriesOnly, pushPreviousLocation = false)
+        model.searchResult.observe(this) { result ->
+            recyclerAdapter.submitList(result.passwordItems)
+        }
+    }
+
     override fun onAttach(context: Context) {
         super.onAttach(context)
         try {
             listener = object : OnFragmentInteractionListener {
                 override fun onFragmentInteraction(item: PasswordItem) {
                     if (item.type == PasswordItem.TYPE_CATEGORY) {
-                        // push the category were we're going
+                        model.navigateTo(item.file, listMode = ListMode.DirectoriesOnly)
-                        pathStack.push(item.file)
-                        recyclerView.scrollToPosition(0)
-                        recyclerAdapter.clear()
-                        recyclerAdapter.addAll(getPasswords(
-                                item.file,
-                                getRepositoryDirectory(context),
-                                sortOrder)
-                        )
                         (requireActivity() as AppCompatActivity).supportActionBar?.setDisplayHomeAsUpEnabled(true)
                     }
                 }
@@ -91,16 +79,8 @@ class SelectFolderFragment : Fragment() {
         }
     }
 
-    /**
+    val currentDir: File
-     * gets the current directory
+        get() = model.currentDir.value!!
-     *
-     * @return the current directory
-     */
-    val currentDir: File?
-        get() = if (pathStack.isEmpty()) getRepositoryDirectory(requireContext()) else pathStack.peek()
-
-    private val sortOrder: PasswordRepository.PasswordSortOrder
-        get() = getSortOrder(PreferenceManager.getDefaultSharedPreferences(requireContext()))
 
     interface OnFragmentInteractionListener {
         fun onFragmentInteraction(item: PasswordItem)

app/src/main/java/com/zeapo/pwdstore/autofill/oreo/ui/AutofillFilterActivity.kt

@@ -19,15 +19,15 @@ import androidx.core.text.bold
 import androidx.core.text.buildSpannedString
 import androidx.core.text.underline
 import androidx.core.widget.addTextChangedListener
-import androidx.lifecycle.Observer
 import androidx.lifecycle.ViewModelProvider
-import androidx.recyclerview.widget.DividerItemDecoration
+import androidx.lifecycle.observe
 import androidx.recyclerview.widget.LinearLayoutManager
 import com.github.ajalt.timberkt.e
-import com.zeapo.pwdstore.DelegatedSearchableRepositoryAdapter
 import com.zeapo.pwdstore.FilterMode
+import com.zeapo.pwdstore.ListMode
 import com.zeapo.pwdstore.R
 import com.zeapo.pwdstore.SearchMode
+import com.zeapo.pwdstore.SearchableRepositoryAdapter
 import com.zeapo.pwdstore.SearchableRepositoryViewModel
 import com.zeapo.pwdstore.autofill.oreo.AutofillMatcher
 import com.zeapo.pwdstore.autofill.oreo.AutofillPreferences
@@ -35,11 +35,7 @@ import com.zeapo.pwdstore.autofill.oreo.DirectoryStructure
 import com.zeapo.pwdstore.autofill.oreo.FormOrigin
 import com.zeapo.pwdstore.utils.PasswordItem
 import kotlinx.android.synthetic.main.activity_oreo_autofill_filter.*
-import kotlinx.coroutines.ExperimentalCoroutinesApi
-import kotlinx.coroutines.FlowPreview
 
-@FlowPreview
-@ExperimentalCoroutinesApi
 @TargetApi(Build.VERSION_CODES.O)
 class AutofillFilterView : AppCompatActivity() {
 
@@ -116,10 +112,9 @@ class AutofillFilterView : AppCompatActivity() {
     }
 
     private fun bindUI() {
-        val searchableAdapter = DelegatedSearchableRepositoryAdapter(
+        val recyclerAdapter = SearchableRepositoryAdapter(
             R.layout.oreo_autofill_filter_row,
-            ::PasswordViewHolder
+            ::PasswordViewHolder) { item ->
-        ) { item ->
             val file = item.file.relativeTo(item.rootDir)
             val pathToIdentifier = directoryStructure.getPathToIdentifierFor(file)
             val identifier = directoryStructure.getIdentifierFor(file) ?: "INVALID"
@@ -129,12 +124,12 @@ class AutofillFilterView : AppCompatActivity() {
                 bold { underline { append(identifier) } }
             }
             subtitle.text = accountPart
-            itemView.setOnClickListener { decryptAndFill(item) }
+        }.onItemClicked { _, item ->
+            decryptAndFill(item)
         }
         rvPassword.apply {
-            adapter = searchableAdapter
+            adapter = recyclerAdapter
             layoutManager = LinearLayoutManager(context)
-            addItemDecoration(DividerItemDecoration(context, DividerItemDecoration.VERTICAL))
         }
 
         val initialFilter = formOrigin.getPrettyIdentifier(applicationContext, untrusted = false)
@@ -145,26 +140,26 @@ class AutofillFilterView : AppCompatActivity() {
             initialFilter,
             filterMode = filterMode,
             searchMode = SearchMode.RecursivelyInSubdirectories,
-            listFilesOnly = true
+            listMode = ListMode.FilesOnly
         )
         search.addTextChangedListener {
             model.search(
-                it.toString(),
+                it.toString().trim(),
                 filterMode = FilterMode.Fuzzy,
                 searchMode = SearchMode.RecursivelyInSubdirectories,
-                listFilesOnly = true
+                listMode = ListMode.FilesOnly
             )
         }
-        model.passwordItemsList.observe(
+        model.searchResult.observe(this) { result ->
-            this,
+            val list = result.passwordItems
-            Observer { list ->
+            recyclerAdapter.submitList(list)
-                searchableAdapter.submitList(list)
             // Switch RecyclerView out for a "no results" message if the new list is empty and
             // the message is not yet shown (and vice versa).
             if ((list.isEmpty() && rvPasswordSwitcher.nextView.id == rvPasswordEmpty.id) ||
-                    (list.isNotEmpty() && rvPasswordSwitcher.nextView.id == rvPassword.id))
+                (list.isNotEmpty() && rvPasswordSwitcher.nextView.id == rvPassword.id)
+            )
                 rvPasswordSwitcher.showNext()
-            })
+        }
 
         shouldMatch.text = getString(
             R.string.oreo_autofill_match_with,

app/src/main/java/com/zeapo/pwdstore/git/GitAsyncTask.java

@@ -131,7 +131,7 @@ public class GitAsyncTask extends AsyncTask<GitCommand, Integer, String> {
 
             if (refreshListOnEnd) {
                 try {
-                    ((PasswordStore) this.getActivity()).updateListAdapter();
+                    ((PasswordStore) this.getActivity()).resetPasswordList();
                 } catch (ClassCastException e) {
                     // oups, mistake
                 }

app/src/main/java/com/zeapo/pwdstore/ui/OnOffItemAnimator.kt

@@ -0,0 +1,71 @@
+/*
+ * Copyright © 2014-2020 The Android Password Store Authors. All Rights Reserved.
+ * SPDX-License-Identifier: GPL-3.0-only
+ */
+package com.zeapo.pwdstore.ui
+
+import androidx.recyclerview.widget.DefaultItemAnimator
+import androidx.recyclerview.widget.RecyclerView
+
+class OnOffItemAnimator : DefaultItemAnimator() {
+
+    var isEnabled: Boolean = true
+        set(value) {
+            // Defer update until no animation is running anymore.
+            isRunning { field = value }
+        }
+
+    private fun dontAnimate(viewHolder: RecyclerView.ViewHolder): Boolean {
+        dispatchAnimationFinished(viewHolder)
+        return false
+    }
+
+    override fun animateAppearance(
+        viewHolder: RecyclerView.ViewHolder,
+        preLayoutInfo: ItemHolderInfo?,
+        postLayoutInfo: ItemHolderInfo
+    ): Boolean {
+        return if (isEnabled) {
+            super.animateAppearance(viewHolder, preLayoutInfo, postLayoutInfo)
+        } else {
+            dontAnimate(viewHolder)
+        }
+    }
+
+    override fun animateChange(
+        oldHolder: RecyclerView.ViewHolder,
+        newHolder: RecyclerView.ViewHolder,
+        preInfo: ItemHolderInfo,
+        postInfo: ItemHolderInfo
+    ): Boolean {
+        return if (isEnabled) {
+            super.animateChange(oldHolder, newHolder, preInfo, postInfo)
+        } else {
+            dontAnimate(oldHolder)
+        }
+    }
+
+    override fun animateDisappearance(
+        viewHolder: RecyclerView.ViewHolder,
+        preLayoutInfo: ItemHolderInfo,
+        postLayoutInfo: ItemHolderInfo?
+    ): Boolean {
+        return if (isEnabled) {
+            super.animateDisappearance(viewHolder, preLayoutInfo, postLayoutInfo)
+        } else {
+            dontAnimate(viewHolder)
+        }
+    }
+
+    override fun animatePersistence(
+        viewHolder: RecyclerView.ViewHolder,
+        preInfo: ItemHolderInfo,
+        postInfo: ItemHolderInfo
+    ): Boolean {
+        return if (isEnabled) {
+            super.animatePersistence(viewHolder, preInfo, postInfo)
+        } else {
+            dontAnimate(viewHolder)
+        }
+    }
+}

app/src/main/java/com/zeapo/pwdstore/ui/adapters/EntryRecyclerAdapter.kt

@@ -1,148 +0,0 @@
-/*
- * Copyright © 2014-2020 The Android Password Store Authors. All Rights Reserved.
- * SPDX-License-Identifier: GPL-3.0-only
- */
-package com.zeapo.pwdstore.ui.adapters
-
-import android.content.SharedPreferences
-import android.text.SpannableString
-import android.text.style.RelativeSizeSpan
-import android.view.LayoutInflater
-import android.view.View
-import android.view.ViewGroup
-import androidx.appcompat.widget.AppCompatImageView
-import androidx.appcompat.widget.AppCompatTextView
-import androidx.preference.PreferenceManager
-import androidx.recyclerview.widget.RecyclerView
-import com.zeapo.pwdstore.R
-import com.zeapo.pwdstore.utils.PasswordItem
-import com.zeapo.pwdstore.widget.MultiselectableConstraintLayout
-import java.io.File
-import java.util.ArrayList
-import java.util.Locale
-import java.util.TreeSet
-import me.zhanghai.android.fastscroll.PopupTextProvider
-
-abstract class EntryRecyclerAdapter internal constructor(val values: ArrayList<PasswordItem>) : RecyclerView.Adapter<EntryRecyclerAdapter.ViewHolder>(), PopupTextProvider {
-    internal val selectedItems: MutableSet<Int> = TreeSet()
-    internal var settings: SharedPreferences? = null
-
-    // Return the size of your dataset (invoked by the layout manager)
-    override fun getItemCount(): Int {
-        return values.size
-    }
-
-    override fun getPopupText(position: Int): String {
-        return values[position].name[0].toString().toUpperCase(Locale.getDefault())
-    }
-
-    fun clear() {
-        this.values.clear()
-        this.notifyDataSetChanged()
-    }
-
-    fun addAll(list: ArrayList<PasswordItem>) {
-        this.values.addAll(list)
-        this.notifyDataSetChanged()
-    }
-
-    fun add(item: PasswordItem) {
-        this.values.add(item)
-        this.notifyItemInserted(itemCount)
-    }
-
-    internal fun toggleSelection(position: Int) {
-        if (!selectedItems.remove(position)) {
-            selectedItems.add(position)
-        }
-    }
-
-    // use this after an item is removed to update the positions of items in set
-    // that followed the removed position
-    fun updateSelectedItems(position: Int, selectedItems: MutableSet<Int>) {
-        val temp = TreeSet<Int>()
-        for (selected in selectedItems) {
-            if (selected > position) {
-                temp.add(selected - 1)
-            } else {
-                temp.add(selected)
-            }
-        }
-        selectedItems.clear()
-        selectedItems.addAll(temp)
-    }
-
-    fun remove(position: Int) {
-        this.values.removeAt(position)
-        this.notifyItemRemoved(position)
-
-        // keep selectedItems updated so we know what to notifyItemChanged
-        // (instead of just using notifyDataSetChanged)
-        updateSelectedItems(position, selectedItems)
-    }
-
-    internal open fun getOnLongClickListener(holder: ViewHolder, pass: PasswordItem): View.OnLongClickListener {
-        return View.OnLongClickListener { false }
-    }
-
-    // Replace the contents of a view (invoked by the layout manager)
-    override fun onBindViewHolder(holder: ViewHolder, position: Int) {
-        settings = settings
-                ?: PreferenceManager.getDefaultSharedPreferences(holder.view.context.applicationContext)
-        val pass = values[position]
-        val showHidden = settings?.getBoolean("show_hidden_folders", false) ?: false
-        holder.name.text = pass.toString()
-        if (pass.type == PasswordItem.TYPE_CATEGORY) {
-            holder.typeImage.setImageResource(R.drawable.ic_multiple_files_24dp)
-            holder.folderIndicator.visibility = View.VISIBLE
-            val children = pass.file.listFiles { pathname ->
-                !(!showHidden && (pathname.isDirectory && pathname.isHidden))
-            } ?: emptyArray<File>()
-            val childCount = children.size
-            holder.childCount.visibility = if (childCount > 0) View.VISIBLE else View.GONE
-            holder.childCount.text = "$childCount"
-        } else {
-            holder.typeImage.setImageResource(R.drawable.ic_action_secure_24dp)
-            val parentPath = pass.fullPathToParent.replace("(^/)|(/$)".toRegex(), "")
-            val source = "$parentPath\n$pass"
-            val spannable = SpannableString(source)
-            spannable.setSpan(RelativeSizeSpan(0.7f), 0, parentPath.length, 0)
-            holder.name.text = spannable
-            holder.childCount.visibility = View.GONE
-            holder.folderIndicator.visibility = View.GONE
-        }
-        holder.view.setOnClickListener(getOnClickListener(holder, pass))
-        holder.view.setOnLongClickListener(getOnLongClickListener(holder, pass))
-
-        // after removal, everything is rebound for some reason; views are shuffled?
-        val selected = selectedItems.contains(position)
-        holder.view.isSelected = selected
-        (holder.itemView as MultiselectableConstraintLayout).setMultiSelected(selected)
-    }
-
-    protected abstract fun getOnClickListener(holder: ViewHolder, pass: PasswordItem): View.OnClickListener
-
-    // Create new views (invoked by the layout manager)
-    override fun onCreateViewHolder(
-        parent: ViewGroup,
-        viewType: Int
-    ): ViewHolder {
-        // create a new view
-        val v = LayoutInflater.from(parent.context)
-                .inflate(R.layout.password_row_layout, parent, false)
-        return ViewHolder(v)
-    }
-
-    /*
-     Provide a reference to the views for each data item
-     Complex data items may need more than one view per item, and
-     you provide access to all the views for a data item in a view holder
-     each data item is just a string in this case
-    */
-    class ViewHolder(val view: View) : RecyclerView.ViewHolder(view) {
-        val name: AppCompatTextView = view.findViewById(R.id.label)
-        val typeImage: AppCompatImageView = view.findViewById(R.id.type_image)
-        val childCount: AppCompatTextView = view.findViewById(R.id.child_count)
-        val folderIndicator: AppCompatImageView = view.findViewById(R.id.folder_indicator)
-    }
-}

app/src/main/java/com/zeapo/pwdstore/ui/adapters/FolderRecyclerAdapter.kt

@@ -1,23 +0,0 @@
-/*
- * Copyright © 2014-2020 The Android Password Store Authors. All Rights Reserved.
- * SPDX-License-Identifier: GPL-3.0-only
- */
-package com.zeapo.pwdstore.ui.adapters
-
-import android.view.View
-import com.zeapo.pwdstore.SelectFolderFragment
-import com.zeapo.pwdstore.utils.PasswordItem
-import java.util.ArrayList
-
-class FolderRecyclerAdapter(
-    private val listener: SelectFolderFragment.OnFragmentInteractionListener,
-    values: ArrayList<PasswordItem>
-) : EntryRecyclerAdapter(values) {
-
-    override fun getOnClickListener(holder: ViewHolder, pass: PasswordItem): View.OnClickListener {
-        return View.OnClickListener {
-            listener.onFragmentInteraction(pass)
-            notifyItemChanged(holder.adapterPosition)
-        }
-    }
-}

app/src/main/java/com/zeapo/pwdstore/ui/adapters/PasswordItemRecyclerAdapter.kt

@@ -0,0 +1,88 @@
+/*
+ * Copyright © 2014-2020 The Android Password Store Authors. All Rights Reserved.
+ * SPDX-License-Identifier: GPL-3.0-only
+ */
+package com.zeapo.pwdstore.ui.adapters
+
+import android.text.SpannableString
+import android.text.style.RelativeSizeSpan
+import android.view.MotionEvent
+import android.view.View
+import androidx.appcompat.widget.AppCompatImageView
+import androidx.appcompat.widget.AppCompatTextView
+import androidx.preference.PreferenceManager
+import androidx.recyclerview.selection.ItemDetailsLookup
+import androidx.recyclerview.selection.Selection
+import androidx.recyclerview.widget.RecyclerView
+import com.zeapo.pwdstore.R
+import com.zeapo.pwdstore.SearchableRepositoryAdapter
+import com.zeapo.pwdstore.stableId
+import com.zeapo.pwdstore.utils.PasswordItem
+import java.io.File
+
+open class PasswordItemRecyclerAdapter :
+    SearchableRepositoryAdapter<PasswordItemRecyclerAdapter.PasswordItemViewHolder>(
+        R.layout.password_row_layout,
+        ::PasswordItemViewHolder,
+        PasswordItemViewHolder::bind
+    ) {
+
+    fun makeSelectable(recyclerView: RecyclerView) {
+        makeSelectable(recyclerView, ::PasswordItemDetailsLookup)
+    }
+
+    override fun onItemClicked(listener: (holder: PasswordItemViewHolder, item: PasswordItem) -> Unit): PasswordItemRecyclerAdapter {
+        return super.onItemClicked(listener) as PasswordItemRecyclerAdapter
+    }
+
+    override fun onSelectionChanged(listener: (selection: Selection<String>) -> Unit): PasswordItemRecyclerAdapter {
+        return super.onSelectionChanged(listener) as PasswordItemRecyclerAdapter
+    }
+
+    class PasswordItemViewHolder(view: View) : RecyclerView.ViewHolder(view) {
+        private val name: AppCompatTextView = itemView.findViewById(R.id.label)
+        private val typeImage: AppCompatImageView = itemView.findViewById(R.id.type_image)
+        private val childCount: AppCompatTextView = itemView.findViewById(R.id.child_count)
+        private val folderIndicator: AppCompatImageView =
+            itemView.findViewById(R.id.folder_indicator)
+        lateinit var itemDetails: ItemDetailsLookup.ItemDetails<String>
+
+        fun bind(item: PasswordItem) {
+            val settings =
+                PreferenceManager.getDefaultSharedPreferences(itemView.context.applicationContext)
+            val showHidden = settings.getBoolean("show_hidden_folders", false)
+            name.text = item.toString()
+            if (item.type == PasswordItem.TYPE_CATEGORY) {
+                typeImage.setImageResource(R.drawable.ic_multiple_files_24dp)
+                folderIndicator.visibility = View.VISIBLE
+                val children = item.file.listFiles { pathname ->
+                    !(!showHidden && (pathname.isDirectory && pathname.isHidden))
+                } ?: emptyArray<File>()
+                val count = children.size
+                childCount.visibility = if (count > 0) View.VISIBLE else View.GONE
+                childCount.text = "$count"
+            } else {
+                typeImage.setImageResource(R.drawable.ic_action_secure_24dp)
+                val parentPath = item.fullPathToParent.replace("(^/)|(/$)".toRegex(), "")
+                val source = "$parentPath\n$item"
+                val spannable = SpannableString(source)
+                spannable.setSpan(RelativeSizeSpan(0.7f), 0, parentPath.length, 0)
+                name.text = spannable
+                childCount.visibility = View.GONE
+                folderIndicator.visibility = View.GONE
+            }
+            itemDetails = object : ItemDetailsLookup.ItemDetails<String>() {
+                override fun getPosition() = absoluteAdapterPosition
+                override fun getSelectionKey() = item.stableId
+            }
+        }
+    }
+
+    class PasswordItemDetailsLookup(private val recyclerView: RecyclerView) :
+        ItemDetailsLookup<String>() {
+        override fun getItemDetails(event: MotionEvent): ItemDetails<String>? {
+            val view = recyclerView.findChildViewUnder(event.x, event.y) ?: return null
+            return (recyclerView.getChildViewHolder(view) as PasswordItemViewHolder).itemDetails
+        }
+    }
+}

app/src/main/java/com/zeapo/pwdstore/ui/adapters/PasswordRecyclerAdapter.kt

@@ -1,120 +0,0 @@
-/*
- * Copyright © 2014-2020 The Android Password Store Authors. All Rights Reserved.
- * SPDX-License-Identifier: GPL-3.0-only
- */
-package com.zeapo.pwdstore.ui.adapters
-
-import android.view.Menu
-import android.view.MenuItem
-import android.view.View
-import androidx.appcompat.view.ActionMode
-import com.zeapo.pwdstore.PasswordFragment
-import com.zeapo.pwdstore.PasswordStore
-import com.zeapo.pwdstore.R
-import com.zeapo.pwdstore.utils.PasswordItem
-import java.util.ArrayList
-import java.util.TreeSet
-
-class PasswordRecyclerAdapter(
-    private val activity: PasswordStore,
-    private val listener: PasswordFragment.OnFragmentInteractionListener,
-    values: ArrayList<PasswordItem>
-) : EntryRecyclerAdapter(values) {
-    var actionMode: ActionMode? = null
-    private var canEdit: Boolean = false
-    private val actionModeCallback = object : ActionMode.Callback {
-
-        // Called when the action mode is created; startActionMode() was called
-        override fun onCreateActionMode(mode: ActionMode, menu: Menu): Boolean {
-            // Inflate a menu resource providing context menu items
-            mode.menuInflater.inflate(R.menu.context_pass, menu)
-            // hide the fab
-            activity.findViewById<View>(R.id.fab).visibility = View.GONE
-            return true
-        }
-
-        // Called each time the action mode is shown. Always called after onCreateActionMode, but
-        // may be called multiple times if the mode is invalidated.
-        override fun onPrepareActionMode(mode: ActionMode, menu: Menu): Boolean {
-            menu.findItem(R.id.menu_edit_password).isVisible = canEdit
-            return true // Return false if nothing is done
-        }
-
-        // Called when the user selects a contextual menu item
-        override fun onActionItemClicked(mode: ActionMode, item: MenuItem): Boolean {
-            when (item.itemId) {
-                R.id.menu_delete_password -> {
-                    activity.deletePasswords(this@PasswordRecyclerAdapter, TreeSet(selectedItems))
-                    mode.finish() // Action picked, so close the CAB
-                    return true
-                }
-                R.id.menu_edit_password -> {
-                    activity.editPassword(values[selectedItems.iterator().next()])
-                    mode.finish()
-                    return true
-                }
-                R.id.menu_move_password -> {
-                    val selectedPasswords = ArrayList<PasswordItem>()
-                    for (id in selectedItems) {
-                        selectedPasswords.add(values[id])
-                    }
-                    activity.movePasswords(selectedPasswords)
-                    return false
-                }
-                else -> return false
-            }
-        }
-
-        // Called when the user exits the action mode
-        override fun onDestroyActionMode(mode: ActionMode) {
-            val it = selectedItems.iterator()
-            while (it.hasNext()) {
-                // need the setSelected line in onBind
-                notifyItemChanged(it.next())
-                it.remove()
-            }
-            actionMode = null
-            // show the fab
-            activity.findViewById<View>(R.id.fab).visibility = View.VISIBLE
-        }
-    }
-
-    override fun getOnLongClickListener(holder: ViewHolder, pass: PasswordItem): View.OnLongClickListener {
-        return View.OnLongClickListener {
-            if (actionMode != null) {
-                return@OnLongClickListener false
-            }
-            toggleSelection(holder.adapterPosition)
-            canEdit = pass.type == PasswordItem.TYPE_PASSWORD
-            // Start the CAB using the ActionMode.Callback
-            actionMode = activity.startSupportActionMode(actionModeCallback)
-            actionMode?.title = "" + selectedItems.size
-            actionMode?.invalidate()
-            notifyItemChanged(holder.adapterPosition)
-            true
-        }
-    }
-
-    override fun getOnClickListener(holder: ViewHolder, pass: PasswordItem): View.OnClickListener {
-        return View.OnClickListener {
-            if (actionMode != null) {
-                toggleSelection(holder.adapterPosition)
-                actionMode?.title = "" + selectedItems.size
-                if (selectedItems.isEmpty()) {
-                    actionMode?.finish()
-                } else if (selectedItems.size == 1 && (canEdit.not())) {
-                    if (values[selectedItems.iterator().next()].type == PasswordItem.TYPE_PASSWORD) {
-                        canEdit = true
-                        actionMode?.invalidate()
-                    }
-                } else if (selectedItems.size >= 1 && canEdit) {
-                    canEdit = false
-                    actionMode?.invalidate()
-                }
-            } else {
-                listener.onFragmentInteraction(pass)
-            }
-            notifyItemChanged(holder.adapterPosition)
-        }
-    }
-}

app/src/main/java/com/zeapo/pwdstore/ui/dialogs/FolderCreationDialogFragment.kt

@@ -48,7 +48,7 @@ class FolderCreationDialogFragment : DialogFragment() {
         val materialTextView = dialog.findViewById<TextInputEditText>(R.id.folder_name_text)
         val folderName = materialTextView.text.toString()
         File("$currentDir/$folderName").mkdir()
-        (requireActivity() as PasswordStore).updateListAdapter()
+        (requireActivity() as PasswordStore).refreshPasswordList()
         dismiss()
     }
 

app/src/main/java/com/zeapo/pwdstore/widget/MultiselectableConstraintLayout.kt

@@ -1,41 +0,0 @@
-/*
- * Copyright © 2014-2020 The Android Password Store Authors. All Rights Reserved.
- * SPDX-License-Identifier: GPL-3.0-only
- */
-package com.zeapo.pwdstore.widget
-
-import android.content.Context
-import android.util.AttributeSet
-import android.view.View
-import androidx.constraintlayout.widget.ConstraintLayout
-import com.zeapo.pwdstore.R
-
-class MultiselectableConstraintLayout @JvmOverloads constructor(
-    context: Context,
-    attrs: AttributeSet? = null,
-    defStyleAttr: Int = 0,
-    defStyleRes: Int = 0
-) : ConstraintLayout(context, attrs, defStyleAttr, defStyleRes) {
-    private var multiselected: Boolean = false
-
-    override fun onCreateDrawableState(extraSpace: Int): IntArray {
-        if (multiselected) {
-            val drawableState = super.onCreateDrawableState(extraSpace + 1)
-            View.mergeDrawableStates(drawableState, STATE_MULTISELECTED)
-            return drawableState
-        }
-        return super.onCreateDrawableState(extraSpace)
-    }
-
-    fun setMultiSelected(on: Boolean) {
-        if (!multiselected) {
-            multiselected = true
-            refreshDrawableState()
-        }
-        isActivated = on
-    }
-
-    companion object {
-        private val STATE_MULTISELECTED = intArrayOf(R.attr.state_multiselected)
-    }
-}

app/src/main/res/drawable/password_row_background.xml

@@ -1,12 +1,14 @@
 <?xml version="1.0" encoding="utf-8"?>
-<layer-list xmlns:android="http://schemas.android.com/apk/res/android"
+<!--
-    xmlns:app="http://schemas.android.com/apk/res-auto">
+Requires a layer-list since attributes cannot be resolved in selectors, see:
+https://stackoverflow.com/a/36424426/297261
+ -->
+<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
 <item>
     <selector>
-            <item app:state_multiselected="true" android:state_activated="true">
+        <item android:drawable="@color/list_multiselect_background" android:state_selected="true" />
-                <color android:color="@color/list_multiselect_background" />
+        <item android:drawable="@android:color/transparent"/>
-            </item>
     </selector>
 </item>
-    <item android:drawable="?attr/selectableItemBackground" />
+<item android:drawable="?android:attr/selectableItemBackground"/>
 </layer-list>

app/src/main/res/layout/oreo_autofill_filter_row.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<com.zeapo.pwdstore.widget.MultiselectableConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
@@ -61,4 +61,4 @@
         app:layout_constraintStart_toEndOf="@id/title"
         app:layout_constraintTop_toTopOf="parent" />
 
-</com.zeapo.pwdstore.widget.MultiselectableConstraintLayout>
+</androidx.constraintlayout.widget.ConstraintLayout>

app/src/main/res/layout/password_row_layout.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<com.zeapo.pwdstore.widget.MultiselectableConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:tools="http://schemas.android.com/tools"
     xmlns:app="http://schemas.android.com/apk/res-auto"
     android:layout_width="match_parent"
@@ -52,4 +52,4 @@
         app:layout_constraintTop_toTopOf="parent"
         app:layout_constraintBottom_toBottomOf="parent" />
 
-</com.zeapo.pwdstore.widget.MultiselectableConstraintLayout>
+</androidx.constraintlayout.widget.ConstraintLayout>

app/src/main/res/values-ru/strings.xml

@@ -318,8 +318,6 @@
     <string name="button_create">Создать</string>
     <string name="pref_search_on_start">Открыть поиск на старте</string>
     <string name="pref_search_on_start_hint">Открыть панель поиска при запуске приложения</string>
-    <string name="pref_search_from_root">Всегда начинать поиск от корня</string>
-    <string name="pref_search_from_root_hint">Искать от корня хранилища независимо от текущей открытой директории</string>
     <string name="password_generator_category_title">Генератор паролей</string>
     <string name="tap_clear_clipboard">Нажмите здесь чтобы очистить буфер обмена</string>
     <string name="clone_git_repo">Для синхронизации изменений клонируйте git репозиторий</string>

app/src/main/res/values/strings.xml

@@ -1,6 +1,11 @@
 <?xml version="1.0" encoding="utf-8"?>
 <resources>
 
+    <plurals name="delete_title">
+        <item quantity="one">%d item selected</item>
+        <item quantity="other">%d items selected</item>
+    </plurals>
+
     <!-- Activity names -->
     <string name="app_name" translatable="false">Password Store</string>
 
@@ -330,8 +335,6 @@
     <string name="button_create">Create</string>
     <string name="pref_search_on_start">Open search on start</string>
     <string name="pref_search_on_start_hint">Open search bar when app is launched</string>
-    <string name="pref_search_from_root">Always search from root</string>
-    <string name="pref_search_from_root_hint">Search from root of store regardless of currently open directory</string>
     <string name="password_generator_category_title">Password Generator</string>
     <string name="tap_clear_clipboard">Tap here to clear clipboard</string>
     <string name="clone_git_repo">Clone a git repository to sync changes</string>

app/src/main/res/xml/preference.xml

@@ -147,11 +147,6 @@
             app:key="search_on_start"
             app:summary="@string/pref_search_on_start_hint"
             app:title="@string/pref_search_on_start" />
-        <androidx.preference.CheckBoxPreference
-            app:defaultValue="false"
-            app:key="search_from_root"
-            app:summary="@string/pref_search_from_root_hint"
-            app:title="@string/pref_search_from_root" />
         <androidx.preference.ListPreference
             app:title="@string/pref_sort_order_title"
             app:defaultValue="FOLDER_FIRST"

dependencies.gradle

@@ -37,18 +37,19 @@ ext.deps = [
         documentfile: 'androidx.documentfile:documentfile:1.0.1',
         fragment_ktx: 'androidx.fragment:fragment-ktx:1.1.0',
         lifecycle_livedata_ktx: 'androidx.lifecycle:lifecycle-livedata-ktx:2.3.0-alpha01',
-        lifecycle_runtime_ktx: 'androidx.lifecycle:lifecycle-runtime-ktx:2.3.0-alpha01',
+        lifecycle_viewmodel_ktx: 'androidx.lifecycle:lifecycle-viewmodel-ktx:2.3.0-alpha01',
         local_broadcast_manager: 'androidx.localbroadcastmanager:localbroadcastmanager:1.1.0-alpha01',
         material: 'com.google.android.material:material:1.2.0-alpha05',
         preference: 'androidx.preference:preference:1.1.0',
-        recycler_view: 'androidx.recyclerview:recyclerview:1.2.0-alpha01',
+        recycler_view: 'androidx.recyclerview:recyclerview:1.2.0-alpha02',
+        recycler_view_selection: 'androidx.recyclerview:recyclerview-selection:1.1.0-rc01',
         swiperefreshlayout: 'androidx.swiperefreshlayout:swiperefreshlayout:1.1.0-beta01'
     ],
 
     third_party: [
         commons_io: 'commons-io:commons-io:2.5',
         commons_codec: 'commons-codec:commons-codec:1.13',
-        fastscroll: 'me.zhanghai.android.fastscroll:library:1.1.1',
+        fastscroll: 'me.zhanghai.android.fastscroll:library:1.1.2',
         jsch: 'com.jcraft:jsch:0.1.55',
         jgit: 'org.eclipse.jgit:org.eclipse.jgit:3.7.1.201504261725-r',
         leakcanary: 'com.squareup.leakcanary:leakcanary-android:2.2',