Swipe delete without reloading all of the cards and add some comments and other cleanup

We can use adapter.notifyItemRemoved and remove it from the cardList in adapater directly since we do understand the position in this case. It works better because it does not require reloading everything and causes less bugs with the view model.

I am not sure if this was the proper way to do this. If not I can revert the change to this method

It also removes the need for a callback in DownloadButtonSetup

app/src/main/java/com/lagradost/cloudstream3/ui/download/DownloadButtonSetup.kt

@@ -1,5 +1,6 @@
 package com.lagradost.cloudstream3.ui.download
 
+import android.app.Activity
 import android.content.DialogInterface
 import android.widget.Toast
 import androidx.appcompat.app.AlertDialog
@@ -19,7 +20,7 @@ import com.lagradost.cloudstream3.utils.VideoDownloadHelper
 import com.lagradost.cloudstream3.utils.VideoDownloadManager
 
 object DownloadButtonSetup {
-    fun handleDownloadClick(click: DownloadClickEvent, deleteCallback: () -> Unit = {}) {
+    fun handleDownloadClick(click: DownloadClickEvent) {
         val id = click.data.id
         if (click.data !is VideoDownloadHelper.DownloadEpisodeCached) return
         when (click.action) {
@@ -31,7 +32,6 @@ object DownloadButtonSetup {
                             when (which) {
                                 DialogInterface.BUTTON_POSITIVE -> {
                                     VideoDownloadManager.deleteFileAndUpdateSettings(ctx, id)
-                                    deleteCallback.invoke()
                                 }
                                 DialogInterface.BUTTON_NEGATIVE -> {
                                 }

app/src/main/java/com/lagradost/cloudstream3/ui/download/DownloadFragment.kt

@@ -66,7 +66,7 @@ class DownloadFragment : Fragment() {
     @SuppressLint("NotifyDataSetChanged")
     private fun setList(list: List<VisualDownloadHeaderCached>) {
         main {
-            (binding?.downloadList?.adapter as DownloadHeaderAdapter?)?.cardList = list
+            (binding?.downloadList?.adapter as DownloadHeaderAdapter?)?.cardList = list.toMutableList()
             binding?.downloadList?.adapter?.notifyDataSetChanged()
         }
     }
@@ -147,7 +147,7 @@ class DownloadFragment : Fragment() {
                     when (click.action) {
                         0 -> {
                             if (click.data.type.isMovieType()) {
-                                //wont be called
+                                // Won't be called
                             } else {
                                 val folder = DataStore.getFolderName(
                                     DOWNLOAD_EPISODE_CACHE,
@@ -173,26 +173,21 @@ class DownloadFragment : Fragment() {
                     if (downloadClickEvent.data !is VideoDownloadHelper.DownloadEpisodeCached) return@DownloadHeaderAdapter
                     handleDownloadClick(downloadClickEvent)
                     if (downloadClickEvent.action == DOWNLOAD_ACTION_DELETE_FILE) {
-                        context?.let { ctx ->
+                        downloadDeleteEventListener = { id ->
-                            downloadsViewModel.updateList(ctx)
+                            val list = (binding?.downloadList?.adapter as DownloadHeaderAdapter?)?.cardList
+                            if (list != null) {
+                                if (list.any { it.data.id == id }) {
+                                    context?.let { ctx ->
+                                        downloadsViewModel.updateList(ctx)
+                                    }
+                                }
+                            }
                         }
+                        downloadDeleteEventListener?.let { VideoDownloadManager.downloadDeleteEvent += it }
                     }
                 }
             )
 
-        downloadDeleteEventListener = { id ->
-            val list = (binding?.downloadList?.adapter as DownloadHeaderAdapter?)?.cardList
-            if (list != null) {
-                if (list.any { it.data.id == id }) {
-                    context?.let { ctx ->
-                        downloadsViewModel.updateList(ctx)
-                    }
-                }
-            }
-        }
-
-        downloadDeleteEventListener?.let { VideoDownloadManager.downloadDeleteEvent += it }
-
         binding?.downloadList?.apply {
             setHasFixedSize(true)
             setItemViewCacheSize(20)
@@ -203,10 +198,9 @@ class DownloadFragment : Fragment() {
                 nextUp = FOCUS_SELF,
                 nextDown = FOCUS_SELF
             )
-            //layoutManager = GridLayoutManager(context, 1)
 
             val itemTouchHelper = ItemTouchHelper(
-                DownloadSwipeToDeleteCallback(
+                DownloadSwipeDeleteCallback(
                     this.adapter as DownloadHeaderAdapter,
                     context
                 )

app/src/main/java/com/lagradost/cloudstream3/ui/download/DownloadHeaderAdapter.kt

@@ -29,7 +29,7 @@ data class DownloadHeaderClickEvent(
 )
 
 class DownloadHeaderAdapter(
-    var cardList: List<VisualDownloadHeaderCached>,
+    var cardList: MutableList<VisualDownloadHeaderCached>,
     private val clickCallback: (DownloadHeaderClickEvent) -> Unit,
     private val movieClickCallback: (DownloadClickEvent) -> Unit,
 ) : RecyclerView.Adapter<RecyclerView.ViewHolder>() {
@@ -55,7 +55,7 @@ class DownloadHeaderAdapter(
     }
 
     override fun getItemCount(): Int {
-        return cardList.size
+        return cardList.count()
     }
 
     class DownloadHeaderViewHolder
@@ -94,7 +94,7 @@ class DownloadHeaderAdapter(
                 if (card.child != null) {
                     //downloadHeaderProgressDownloaded.visibility = View.VISIBLE
 
-                   // downloadHeaderEpisodeDownload.visibility = View.VISIBLE
+                    // downloadHeaderEpisodeDownload.visibility = View.VISIBLE
                     binding.downloadHeaderGotoChild.visibility = View.GONE
 
                     downloadButton.setDefaultClickListener(card.child, downloadHeaderInfo, movieClickCallback)
@@ -119,8 +119,8 @@ class DownloadHeaderAdapter(
                     }
                 } else {
                     downloadButton.isVisible = false
-                   // downloadHeaderProgressDownloaded.visibility = View.GONE
+                    // downloadHeaderProgressDownloaded.visibility = View.GONE
-                   // downloadHeaderEpisodeDownload.visibility = View.GONE
+                    // downloadHeaderEpisodeDownload.visibility = View.GONE
                     binding.downloadHeaderGotoChild.visibility = View.VISIBLE
 
                     try {
@@ -146,4 +146,4 @@ class DownloadHeaderAdapter(
             }
         }
     }
-}
+}

app/src/main/java/com/lagradost/cloudstream3/ui/download/DownloadSwipeDeleteCallback.kt

@@ -16,12 +16,15 @@ import com.lagradost.cloudstream3.R
 import com.lagradost.cloudstream3.isEpisodeBased
 import com.lagradost.cloudstream3.ui.download.DownloadButtonSetup.handleDownloadClick
 import com.lagradost.cloudstream3.utils.Coroutines.runOnMainThread
+import com.lagradost.cloudstream3.utils.VideoDownloadManager.downloadDeleteEvent
 
-class DownloadSwipeToDeleteCallback(
+class DownloadSwipeDeleteCallback(
     private val adapter: DownloadHeaderAdapter,
     private val context: Context
 ) : ItemTouchHelper.Callback() {
 
+    private var downloadDeleteEventListener: ((Int) -> Unit)? = null
+
     private val swipeOpenItems: MutableSet<Int> = mutableSetOf()
     private val deleteIcon: Drawable? by lazy {
         ContextCompat.getDrawable(context, R.drawable.ic_baseline_delete_outline_24)
@@ -39,7 +42,8 @@ class DownloadSwipeToDeleteCallback(
         val position = viewHolder.bindingAdapterPosition
         val item = adapter.cardList[position]
         return if (item.data.type.isEpisodeBased()) 0 else {
-            makeMovementFlags(0, ItemTouchHelper.LEFT or ItemTouchHelper.RIGHT)
+            val swipeFlags = ItemTouchHelper.LEFT or ItemTouchHelper.RIGHT
+            makeMovementFlags(0, swipeFlags)
         }
     }
 
@@ -102,7 +106,12 @@ class DownloadSwipeToDeleteCallback(
                         itemView.right.toFloat(),
                         itemView.bottom.toFloat()
                     ),
-                    floatArrayOf(0f, 0f, 20f, 20f, 20f, 20f, 0f, 0f),
+                    floatArrayOf(
+                        0f, 0f,    // Top-left corner
+                        20f, 20f,  // Top-right corner
+                        20f, 20f,  // Bottom-right corner
+                        0f, 0f     // Bottom-left corner
+                    ),
                     Path.Direction.CW
                 )
             }
@@ -127,6 +136,14 @@ class DownloadSwipeToDeleteCallback(
         }
     }
 
+    override fun clearView(
+        recyclerView: RecyclerView,
+        viewHolder: RecyclerView.ViewHolder
+    ) {
+        clearDownloadDeleteEvent()
+        super.clearView(recyclerView, viewHolder)
+    }
+
     @SuppressLint("ClickableViewAccessibility")
     private fun setRecyclerViewTouchListener(
         recyclerView: RecyclerView,
@@ -136,14 +153,17 @@ class DownloadSwipeToDeleteCallback(
             if (event.action == MotionEvent.ACTION_UP) {
                 val x = event.x.toInt()
                 val y = event.y.toInt()
-                swipeOpenItems.forEach { pos ->
+                // We use toList() to avoid a very rare edge case
+                // where it gives concurrent modification errors
+                swipeOpenItems.toList().forEach { pos ->
                     val vh = recyclerView.findViewHolderForAdapterPosition(pos)
                     vh?.itemView?.let { swipeItemView ->
                         val backgroundLeft: Int = swipeItemView.right - swipeDistance.toInt()
                         val backgroundXRange: IntRange = backgroundLeft..swipeItemView.right
                         val backgroundYRange: IntRange = swipeItemView.top..swipeItemView.bottom
                         if (x in backgroundXRange && y in backgroundYRange) {
-                            handleDelete(pos)
+                            handleDeleteAction(pos)
+                            addDownloadDeleteEvent(pos, recyclerView)
                             return@setOnTouchListener true
                         }
                     }
@@ -154,11 +174,19 @@ class DownloadSwipeToDeleteCallback(
     }
 
     @SuppressLint("ClickableViewAccessibility")
-    private fun removeRecyclerViewTouchListener(
+    private fun removeRecyclerViewTouchListener(recyclerView: RecyclerView) {
-        recyclerView: RecyclerView
+        // We don't want to unnecessarily listen to unused touch events
-    ): Unit = recyclerView.setOnTouchListener(null)
+        recyclerView.setOnTouchListener(null)
 
-    private fun handleDelete(position: Int) {
+        /**
+         * If we are not listening to touch events, then
+         * we should clear the delete event as it will
+         * not be used at the moment.
+         */
+        clearDownloadDeleteEvent()
+    }
+
+    private fun handleDeleteAction(position: Int) {
         val item = adapter.cardList[position]
         runOnMainThread {
             item.child?.let { clickEvent ->
@@ -167,8 +195,55 @@ class DownloadSwipeToDeleteCallback(
                         DOWNLOAD_ACTION_DELETE_FILE,
                         clickEvent
                     )
-                ) { adapter.notifyItemRemoved(position) }
+                )
             }
         }
     }
+
+    private fun addDownloadDeleteEvent(
+        position: Int,
+        recyclerView: RecyclerView
+    ) {
+        // Clear any old events as we don't want to get
+        // concurrent modification errors
+        clearDownloadDeleteEvent()
+        downloadDeleteEventListener = { id: Int ->
+            val list = adapter.cardList
+            if (list.any { it.data.id == id }) {
+                /**
+                 * Seamlessly remove now-deleted item from adapter.
+                 * We don't need to reload from the viewModel,
+                 * that just causes more unnecessary actions and
+                 * unreliable data to be returned oftentimes,
+                 * as it would cause it to reload the entire
+                 * view model (which is all items) we only want
+                 * to target one item and this provides a more seamless
+                 * and performant solution to it since we do have access to
+                 * the position we need to target here.
+                 */
+                adapter.cardList.removeAt(position)
+                adapter.notifyItemRemoved(position)
+                adapter.notifyItemRangeChanged(
+                    position,
+                    adapter.cardList.size
+                ) // rebind to new positions
+
+                /**
+                 * we need to clear the listener now since nothing should be open
+                 * and it was closed outside of on onChildDraw so we don't
+                 * want to have random unexpected touch events.
+                 */
+                removeRecyclerViewTouchListener(recyclerView)
+            }
+        }
+
+        downloadDeleteEventListener?.let { downloadDeleteEvent += it }
+    }
+
+    private fun clearDownloadDeleteEvent() {
+        if (downloadDeleteEventListener != null) {
+            downloadDeleteEvent -= downloadDeleteEventListener!!
+            downloadDeleteEventListener = null
+        }
+    }
 }