Switch explorer from ListView to RecyclerView

app/src/main/java/sushi/hardcore/droidfs/adapters/ExplorerElementAdapter.kt

@@ -1,14 +1,13 @@
 package sushi.hardcore.droidfs.adapters
 
 import android.content.Context
-import android.graphics.Color
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
-import android.widget.BaseAdapter
 import android.widget.ImageView
+import android.widget.LinearLayout
 import android.widget.TextView
-import androidx.core.content.ContextCompat
+import androidx.recyclerview.widget.RecyclerView
 import sushi.hardcore.droidfs.ConstValues.Companion.getAssociatedDrawable
 import sushi.hardcore.droidfs.R
 import sushi.hardcore.droidfs.explorers.ExplorerElement
@@ -16,79 +15,47 @@ import sushi.hardcore.droidfs.util.PathUtils
 import java.text.DateFormat
 import java.util.*
 
-class ExplorerElementAdapter(private val context: Context) : BaseAdapter() {
+class ExplorerElementAdapter(
-    private val dateFormat: DateFormat = DateFormat.getDateTimeInstance(DateFormat.DEFAULT, DateFormat.DEFAULT, Locale.getDefault())
+    context: Context,
-    private var explorerElements = listOf<ExplorerElement>()
+    private val onExplorerElementClick: (Int) -> Unit,
+    private val onExplorerElementLongClick: (Int) -> Unit
+) : RecyclerView.Adapter<RecyclerView.ViewHolder>() {
+    private val dateFormat = DateFormat.getDateTimeInstance(DateFormat.DEFAULT, DateFormat.DEFAULT, Locale.getDefault())
+    var explorerElements = listOf<ExplorerElement>()
+        set(value) {
+            field = value
+            unSelectAll()
+        }
     private val inflater: LayoutInflater = LayoutInflater.from(context)
     val selectedItems: MutableList<Int> = ArrayList()
-    override fun getCount(): Int {
+
+    override fun getItemCount(): Int {
         return explorerElements.size
     }
 
-    override fun getItem(position: Int): ExplorerElement {
+    private fun toggleSelection(position: Int): Boolean {
-        return explorerElements[position]
+        if (!explorerElements[position].isParentFolder) {
-    }
-
-    override fun getItemId(position: Int): Long {
-        return 0
-    }
-
-    override fun getView(position: Int, convertView: View?, parent: ViewGroup): View {
-        val view: View = convertView ?: inflater.inflate(R.layout.adapter_explorer_element, parent, false)
-        val currentElement = getItem(position)
-        val textElementName = view.findViewById<TextView>(R.id.text_element_name)
-        textElementName.text = currentElement.name
-        val textElementMtime = view.findViewById<TextView>(R.id.text_element_mtime)
-        val textElementSize = view.findViewById<TextView>(R.id.text_element_size)
-        if (!currentElement.isParentFolder){
-            textElementSize.text = PathUtils.formatSize(currentElement.size)
-        } else {
-            textElementSize.text = ""
-        }
-        var drawableId = R.drawable.icon_folder
-        when {
-            currentElement.isDirectory -> {
-                textElementMtime.text = dateFormat.format(currentElement.mTime)
-            }
-            currentElement.isParentFolder -> {
-                textElementMtime.setText(R.string.parent_folder)
-            }
-            else -> {
-                textElementMtime.text = dateFormat.format(currentElement.mTime)
-                drawableId = getAssociatedDrawable(currentElement.name)
-            }
-        }
-        view.findViewById<ImageView>(R.id.icon_element).setImageResource(drawableId)
             if (selectedItems.contains(position)) {
-            view.setBackgroundColor(ContextCompat.getColor(context, R.color.itemSelected))
+                selectedItems.remove(position)
             } else {
-            view.setBackgroundColor(Color.alpha(0))
+                selectedItems.add(position)
+                return true
             }
-        return view
+        }
+        return false
     }
 
-    fun onItemClick(position: Int) {
+    private fun onItemClick(position: Int): Boolean {
+        onExplorerElementClick(position)
         if (selectedItems.isNotEmpty()) {
-            if (!explorerElements[position].isParentFolder) {
+            return toggleSelection(position)
-                if (selectedItems.contains(position)) {
-                    selectedItems.remove(position)
-                } else {
-                    selectedItems.add(position)
-                }
-                notifyDataSetChanged()
-            }
         }
+        return false
     }
 
-    fun onItemLongClick(position: Int) {
+    private fun onItemLongClick(position: Int): Boolean {
-        if (!explorerElements[position].isParentFolder) {
+        onExplorerElementLongClick(position)
-            if (!selectedItems.contains(position)) {
+        return toggleSelection(position)
-                selectedItems.add(position)
-            } else {
-                selectedItems.remove(position)
-            }
-            notifyDataSetChanged()
-        }
     }
 
     fun selectAll() {
@@ -105,8 +72,112 @@ class ExplorerElementAdapter(private val context: Context) : BaseAdapter() {
         notifyDataSetChanged()
     }
 
-    fun setExplorerElements(explorer_elements: List<ExplorerElement>) {
+    open class ExplorerElementViewHolder(
-        this.explorerElements = explorer_elements
+        itemView: View,
-        unSelectAll()
+        private val onClick: (Int) -> Boolean,
+        private val onLongClick: (Int) -> Boolean,
+    ) : RecyclerView.ViewHolder(itemView) {
+        private val textElementName by lazy {
+            itemView.findViewById<TextView>(R.id.text_element_name)
+        }
+        protected val textElementSize: TextView by lazy {
+            itemView.findViewById(R.id.text_element_size)
+        }
+        protected val textElementMtime: TextView by lazy {
+            itemView.findViewById(R.id.text_element_mtime)
+        }
+        protected val icon: ImageView by lazy {
+            itemView.findViewById(R.id.icon_element)
+        }
+        private val selectableContainer: LinearLayout by lazy {
+            itemView.findViewById(R.id.selectable_container)
+        }
+
+        protected fun setBackground(isSelected: Boolean) {
+            itemView.setBackgroundResource(if (isSelected) { R.color.itemSelected } else { 0 })
+        }
+
+        open fun bind(explorerElement: ExplorerElement, position: Int) {
+            textElementName.text = explorerElement.name
+            selectableContainer.setOnClickListener {
+                setBackground(onClick(position))
+            }
+            selectableContainer.setOnLongClickListener {
+                setBackground(onLongClick(position))
+                true
+            }
+        }
+    }
+
+    open class RegularElementViewHolder(
+        itemView: View,
+        private val dateFormat: DateFormat,
+        onClick: (Int) -> Boolean,
+        onLongClick: (Int) -> Boolean,
+    ) : ExplorerElementViewHolder(itemView, onClick, onLongClick) {
+        open fun bind(explorerElement: ExplorerElement, position: Int, isSelected: Boolean) {
+            super.bind(explorerElement, position)
+            textElementSize.text = PathUtils.formatSize(explorerElement.size)
+            textElementMtime.text = dateFormat.format(explorerElement.mTime)
+            setBackground(isSelected)
+        }
+    }
+
+    class FileViewHolder(
+        itemView: View,
+        dateFormat: DateFormat,
+        onClick: (Int) -> Boolean,
+        onLongClick: (Int) -> Boolean,
+    ) : RegularElementViewHolder(itemView, dateFormat, onClick, onLongClick) {
+        override fun bind(explorerElement: ExplorerElement, position: Int, isSelected: Boolean) {
+            super.bind(explorerElement, position, isSelected)
+            icon.setImageResource(getAssociatedDrawable(explorerElement.name))
+        }
+    }
+    class DirectoryViewHolder(
+        itemView: View,
+        dateFormat: DateFormat,
+        onClick: (Int) -> Boolean,
+        onLongClick: (Int) -> Boolean,
+    ) : RegularElementViewHolder(itemView, dateFormat, onClick, onLongClick) {
+        override fun bind(explorerElement: ExplorerElement, position: Int, isSelected: Boolean) {
+            super.bind(explorerElement, position, isSelected)
+            icon.setImageResource(R.drawable.icon_folder)
+        }
+    }
+    class ParentFolderViewHolder(
+        itemView: View,
+        onClick: (Int) -> Boolean,
+        onLongClick: (Int) -> Boolean,
+    ): ExplorerElementViewHolder(itemView, onClick, onLongClick) {
+        override fun bind(explorerElement: ExplorerElement, position: Int) {
+            super.bind(explorerElement, position)
+            textElementSize.text = ""
+            textElementMtime.setText(R.string.parent_folder)
+            icon.setImageResource(R.drawable.icon_folder)
+        }
+    }
+
+    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): RecyclerView.ViewHolder {
+        val view = inflater.inflate(R.layout.adapter_explorer_element, parent, false)
+        return when (viewType) {
+            ExplorerElement.REGULAR_FILE_TYPE -> FileViewHolder(view, dateFormat, ::onItemClick, ::onItemLongClick)
+            ExplorerElement.DIRECTORY_TYPE -> DirectoryViewHolder(view, dateFormat, ::onItemClick, ::onItemLongClick)
+            ExplorerElement.PARENT_FOLDER_TYPE -> ParentFolderViewHolder(view, ::onItemClick, ::onItemLongClick)
+            else -> throw IllegalArgumentException()
+        }
+    }
+
+    override fun onBindViewHolder(holder: RecyclerView.ViewHolder, position: Int) {
+        val element = explorerElements[position]
+        if (element.isParentFolder) {
+            (holder as ParentFolderViewHolder).bind(element, position)
+        } else {
+            (holder as RegularElementViewHolder).bind(element, position, selectedItems.contains(position))
+        }
+    }
+
+    override fun getItemViewType(position: Int): Int {
+        return explorerElements[position].elementType.toInt()
     }
 }

app/src/main/java/sushi/hardcore/droidfs/explorers/BaseExplorerActivity.kt

@@ -11,16 +11,15 @@ import android.view.Menu
 import android.view.MenuItem
 import android.view.View
 import android.view.WindowManager
-import android.widget.AdapterView.OnItemClickListener
-import android.widget.AdapterView.OnItemLongClickListener
 import android.widget.EditText
-import android.widget.ListView
 import android.widget.TextView
 import android.widget.Toast
 import androidx.core.content.ContextCompat
 import androidx.documentfile.provider.DocumentFile
 import androidx.lifecycle.ViewModel
 import androidx.lifecycle.ViewModelProvider
+import androidx.recyclerview.widget.LinearLayoutManager
+import androidx.recyclerview.widget.RecyclerView
 import androidx.swiperefreshlayout.widget.SwipeRefreshLayout
 import sushi.hardcore.droidfs.BaseActivity
 import sushi.hardcore.droidfs.ConstValues
@@ -67,7 +66,7 @@ open class BaseExplorerActivity : BaseActivity() {
     protected var usf_keep_open = false
     private lateinit var toolbar: androidx.appcompat.widget.Toolbar
     private lateinit var titleText: TextView
-    private lateinit var listExplorer: ListView
+    private lateinit var recycler_view_explorer: RecyclerView
     private lateinit var refresher: SwipeRefreshLayout
     private lateinit var textDirEmpty: TextView
     private lateinit var currentPathText: TextView
@@ -88,7 +87,7 @@ open class BaseExplorerActivity : BaseActivity() {
         init()
         toolbar = findViewById(R.id.toolbar)
         titleText = findViewById(R.id.title_text)
-        listExplorer = findViewById(R.id.list_explorer)
+        recycler_view_explorer = findViewById(R.id.recycler_view_explorer)
         refresher = findViewById(R.id.refresher)
         textDirEmpty = findViewById(R.id.text_dir_empty)
         currentPathText = findViewById(R.id.current_path_text)
@@ -96,14 +95,13 @@ open class BaseExplorerActivity : BaseActivity() {
         setSupportActionBar(toolbar)
         title = ""
         titleText.text = getString(R.string.volume, volumeName)
-        explorerAdapter = ExplorerElementAdapter(this)
+        explorerAdapter = ExplorerElementAdapter(this, ::onExplorerItemClick, ::onExplorerItemLongClick)
         explorerViewModel= ViewModelProvider(this).get(ExplorerViewModel::class.java)
         currentDirectoryPath = explorerViewModel.currentDirectoryPath
         setCurrentPath(currentDirectoryPath)
-        listExplorer.apply {
+        recycler_view_explorer.apply {
             adapter = explorerAdapter
-            onItemClickListener = OnItemClickListener { _, _, position, _ -> onExplorerItemClick(position) }
+            layoutManager = LinearLayoutManager(this@BaseExplorerActivity)
-            onItemLongClickListener = OnItemLongClickListener { _, _, position, _ -> onExplorerItemLongClick(position); true }
         }
         refresher.setOnRefreshListener {
             setCurrentPath(currentDirectoryPath)
@@ -172,7 +170,6 @@ open class BaseExplorerActivity : BaseActivity() {
 
     protected open fun onExplorerItemClick(position: Int) {
         val wasSelecting = explorerAdapter.selectedItems.isNotEmpty()
-        explorerAdapter.onItemClick(position)
         if (explorerAdapter.selectedItems.isEmpty()) {
             if (!wasSelecting) {
                 val fullPath = explorerElements[position].fullPath
@@ -203,7 +200,6 @@ open class BaseExplorerActivity : BaseActivity() {
     }
 
     protected open fun onExplorerItemLongClick(position: Int) {
-        explorerAdapter.onItemLongClick(position)
         invalidateOptionsMenu()
     }
 
@@ -262,7 +258,7 @@ open class BaseExplorerActivity : BaseActivity() {
                         )
                     }
                 }
-                explorerAdapter.setExplorerElements(explorerElements)
+                explorerAdapter.explorerElements = explorerElements
             }
         }.start()
     }

app/src/main/java/sushi/hardcore/droidfs/explorers/ExplorerActivity.kt

@@ -235,9 +235,8 @@ class ExplorerActivity : BaseExplorerActivity() {
     }
 
     override fun onExplorerItemLongClick(position: Int) {
+        super.onExplorerItemLongClick(position)
         cancelItemAction()
-        explorerAdapter.onItemLongClick(position)
-        invalidateOptionsMenu()
     }
 
     private fun createNewFile(fileName: String){
@@ -380,7 +379,7 @@ class ExplorerActivity : BaseExplorerActivity() {
                 if (size > 1) {
                     dialog.setMessage(getString(R.string.multiple_delete_confirm, explorerAdapter.selectedItems.size.toString()))
                 } else {
-                    dialog.setMessage(getString(R.string.single_delete_confirm, explorerAdapter.getItem(explorerAdapter.selectedItems[0]).name))
+                    dialog.setMessage(getString(R.string.single_delete_confirm, explorerAdapter.explorerElements[explorerAdapter.selectedItems[0]].name))
                 }
                 dialog.show()
                 true
@@ -441,7 +440,7 @@ class ExplorerActivity : BaseExplorerActivity() {
     private fun removeSelectedItems() {
         var failedItem: String? = null
         for (i in explorerAdapter.selectedItems) {
-            val element = explorerAdapter.getItem(i)
+            val element = explorerAdapter.explorerElements[i]
             val fullPath = PathUtils.pathJoin(currentDirectoryPath, element.name)
             if (element.isDirectory) {
                 val result = gocryptfsVolume.recursiveRemoveDirectory(fullPath)

app/src/main/java/sushi/hardcore/droidfs/explorers/ExplorerActivityPick.kt

@@ -23,7 +23,6 @@ class ExplorerActivityPick : BaseExplorerActivity() {
 
     override fun onExplorerItemClick(position: Int) {
         val wasSelecting = explorerAdapter.selectedItems.isNotEmpty()
-        explorerAdapter.onItemClick(position)
         if (explorerAdapter.selectedItems.isEmpty()) {
             if (!wasSelecting) {
                 val fullPath = PathUtils.pathJoin(currentDirectoryPath, explorerElements[position].name)

app/src/main/java/sushi/hardcore/droidfs/explorers/ExplorerElement.kt

@@ -8,15 +8,19 @@ class ExplorerElement(val name: String, val elementType: Short, var size: Long =
     val fullPath: String = PathUtils.pathJoin(parentPath, name)
 
     val isDirectory: Boolean
-        get() = elementType.toInt() == 0
+        get() = elementType.toInt() == DIRECTORY_TYPE
 
     val isParentFolder: Boolean
-        get() = elementType.toInt() == -1
+        get() = elementType.toInt() == PARENT_FOLDER_TYPE
 
     val isRegularFile: Boolean
-        get() = elementType.toInt() == 1
+        get() = elementType.toInt() == REGULAR_FILE_TYPE
 
     companion object {
+        const val DIRECTORY_TYPE = 0
+        const val PARENT_FOLDER_TYPE = -1
+        const val REGULAR_FILE_TYPE = 1
+
         @JvmStatic
         //this function is needed because I had some problems calling the constructor from JNI, probably due to arguments with default values
         fun new(name: String, elementType: Short, size: Long, mTime: Long, parentPath: String): ExplorerElement {

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

@@ -14,27 +14,7 @@
         android:layout_width="match_parent"
         android:layout_height="match_parent">
 
-        <TextView
+        <include layout="@layout/explorer_content"/>
-            android:id="@+id/text_dir_empty"
-            android:layout_width="match_parent"
-            android:layout_height="match_parent"
-            android:gravity="center"
-            android:textSize="30sp"
-            android:text="@string/dir_empty"
-            android:visibility="invisible"/>
-
-        <androidx.swiperefreshlayout.widget.SwipeRefreshLayout
-            android:id="@+id/refresher"
-            android:layout_width="match_parent"
-            android:layout_height="match_parent">
-
-            <ListView
-                android:id="@+id/list_explorer"
-                android:layout_width="match_parent"
-                android:layout_height="match_parent"
-                style="@style/listViewNoDivider"/>
-
-        </androidx.swiperefreshlayout.widget.SwipeRefreshLayout>
 
         <com.google.android.material.floatingactionbutton.FloatingActionButton
             android:id="@+id/fab"

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

@@ -14,27 +14,7 @@
         android:layout_width="match_parent"
         android:layout_height="match_parent">
 
-        <TextView
+        <include layout="@layout/explorer_content"/>
-            android:id="@+id/text_dir_empty"
-            android:layout_width="match_parent"
-            android:layout_height="match_parent"
-            android:gravity="center"
-            android:textSize="30sp"
-            android:text="@string/dir_empty"
-            android:visibility="invisible"/>
-
-        <androidx.swiperefreshlayout.widget.SwipeRefreshLayout
-            android:id="@+id/refresher"
-            android:layout_width="match_parent"
-            android:layout_height="match_parent">
-
-            <ListView
-                android:id="@+id/list_explorer"
-                android:layout_width="match_parent"
-                android:layout_height="match_parent"
-                style="@style/listViewNoDivider"/>
-
-        </androidx.swiperefreshlayout.widget.SwipeRefreshLayout>
 
     </RelativeLayout>
 

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

@@ -12,27 +12,7 @@
         android:layout_width="match_parent"
         android:layout_height="match_parent">
 
-        <TextView
+        <include layout="@layout/explorer_content"/>
-            android:id="@+id/text_dir_empty"
-            android:layout_width="match_parent"
-            android:layout_height="match_parent"
-            android:gravity="center"
-            android:textSize="30sp"
-            android:text="@string/dir_empty"
-            android:visibility="invisible"/>
-
-        <androidx.swiperefreshlayout.widget.SwipeRefreshLayout
-            android:id="@+id/refresher"
-            android:layout_width="match_parent"
-            android:layout_height="match_parent">
-
-            <ListView
-                android:id="@+id/list_explorer"
-                android:layout_width="match_parent"
-                android:layout_height="match_parent"
-                style="@style/listViewNoDivider"/>
-
-        </androidx.swiperefreshlayout.widget.SwipeRefreshLayout>
 
         <com.google.android.material.floatingactionbutton.FloatingActionButton
             android:id="@+id/fab"

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

@@ -4,6 +4,12 @@
     android:layout_width="match_parent"
     android:layout_height="wrap_content">
 
+    <LinearLayout
+        android:id="@+id/selectable_container"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:background="?attr/selectableItemBackground">
+
         <ImageView
             android:id="@+id/icon_element"
             android:layout_width="50dp"
@@ -45,4 +51,6 @@
 
         </LinearLayout>
 
+    </LinearLayout>
+
 </LinearLayout>

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

@@ -0,0 +1,25 @@
+<?xml version="1.0" encoding="utf-8"?>
+<merge xmlns:android="http://schemas.android.com/apk/res/android">
+
+    <TextView
+        android:id="@+id/text_dir_empty"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:gravity="center"
+        android:textSize="30sp"
+        android:text="@string/dir_empty"
+        android:visibility="invisible"/>
+
+    <androidx.swiperefreshlayout.widget.SwipeRefreshLayout
+        android:id="@+id/refresher"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent">
+
+        <androidx.recyclerview.widget.RecyclerView
+            android:id="@+id/recycler_view_explorer"
+            android:layout_width="match_parent"
+            android:layout_height="match_parent"/>
+
+    </androidx.swiperefreshlayout.widget.SwipeRefreshLayout>
+
+</merge>

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

@@ -53,10 +53,6 @@
         <item name="android:background">@drawable/button_background</item>
     </style>
 
-    <style name="listViewNoDivider">
-        <item name="android:divider">#000000</item>
-        <item name="android:dividerHeight">0dp</item>
-    </style>
     <style name="infoBarTextView">
         <item name="android:ellipsize">start</item>
         <item name="android:singleLine">true</item>