For #13156, #13280 - Use payloads to bind bookmark viewholders.

Change the DiffUtil callback for bookmarks to use the generated equals()
method instead of only checking the title and url fields. This prevents
the BookmarkNode in our state from getting out of sync with the
BookmarkNode the viewholder is bound to.

app/src/main/java/org/mozilla/fenix/library/bookmarks/BookmarkAdapter.kt

@@ -59,9 +59,20 @@ class BookmarkAdapter(val emptyView: View, val interactor: BookmarkViewInteracto
             old[oldItemPosition].guid == new[newItemPosition].guid
 
         override fun areContentsTheSame(oldItemPosition: Int, newItemPosition: Int): Boolean =
+            oldMode::class == newMode::class &&
             old[oldItemPosition] in oldMode.selectedItems == new[newItemPosition] in newMode.selectedItems &&
-                    old[oldItemPosition].title == new[newItemPosition].title &&
+                    old[oldItemPosition] == new[newItemPosition]
-                    old[oldItemPosition].url == new[newItemPosition].url
+
+        override fun getChangePayload(oldItemPosition: Int, newItemPosition: Int): Any? {
+            val oldItem = old[oldItemPosition]
+            val newItem = new[newItemPosition]
+            return BookmarkPayload(
+                titleChanged = oldItem.title != newItem.title,
+                urlChanged = oldItem.url != newItem.url,
+                selectedChanged = oldItem in oldMode.selectedItems != newItem in newMode.selectedItems,
+                modeChanged = oldMode::class != newMode::class
+            )
+        }
 
         override fun getOldListSize(): Int = old.size
         override fun getNewListSize(): Int = new.size
@@ -90,9 +101,36 @@ class BookmarkAdapter(val emptyView: View, val interactor: BookmarkViewInteracto
 
     override fun getItemCount(): Int = tree.size
 
+    override fun onBindViewHolder(
+        holder: BookmarkNodeViewHolder,
+        position: Int,
+        payloads: MutableList<Any>
+    ) {
+        if (payloads.isNotEmpty() && payloads[0] is BookmarkPayload) {
+            holder.bind(tree[position], mode, payloads[0] as BookmarkPayload)
+        } else {
+            super.onBindViewHolder(holder, position, payloads)
+        }
+    }
+
     override fun onBindViewHolder(holder: BookmarkNodeViewHolder, position: Int) {
         holder.bind(tree[position], mode)
     }
 }
 
+/**
+ * A RecyclerView Adapter payload class that contains information about changes to a [BookmarkNode].
+ *
+ * @property titleChanged true if there has been a change to [BookmarkNode.title].
+ * @property urlChanged true if there has been a change to [BookmarkNode.url].
+ * @property selectedChanged true if there has been a change in the BookmarkNode's selected state.
+ * @property modeChanged true if there has been a change in the state's mode type.
+ */
+data class BookmarkPayload(
+    val titleChanged: Boolean,
+    val urlChanged: Boolean,
+    val selectedChanged: Boolean,
+    val modeChanged: Boolean
+)
+
 fun BookmarkNode.inRoots() = enumValues<BookmarkRoot>().any { it.id == guid }

app/src/main/java/org/mozilla/fenix/library/bookmarks/BookmarkView.kt

@@ -139,7 +139,6 @@ class BookmarkView(
     }
 
     fun update(state: BookmarkFragmentState) {
-        val oldMode = mode
         tree = state.tree
         if (state.mode != mode) {
             mode = state.mode
@@ -149,9 +148,6 @@ class BookmarkView(
         }
 
         bookmarkAdapter.updateData(state.tree, mode)
-        if (state.mode != oldMode) {
-            bookmarkAdapter.notifyDataSetChanged()
-        }
 
         when (mode) {
             is BookmarkFragmentState.Mode.Normal -> {

app/src/main/java/org/mozilla/fenix/library/bookmarks/viewholders/BookmarkFolderViewHolder.kt

@@ -14,6 +14,7 @@ import org.mozilla.fenix.ext.showAndEnable
 import org.mozilla.fenix.library.LibrarySiteItemView
 import org.mozilla.fenix.library.SelectionHolder
 import org.mozilla.fenix.library.bookmarks.BookmarkFragmentState
+import org.mozilla.fenix.library.bookmarks.BookmarkPayload
 import org.mozilla.fenix.library.bookmarks.BookmarkViewInteractor
 import org.mozilla.fenix.library.bookmarks.inRoots
 
@@ -28,28 +29,39 @@ class BookmarkFolderViewHolder(
 
     override var item: BookmarkNode? = null
 
+    init {
+        containerView.displayAs(LibrarySiteItemView.ItemType.FOLDER)
+    }
+
     override fun bind(
         item: BookmarkNode,
         mode: BookmarkFragmentState.Mode
     ) {
-        this.item = item
+        bind(item, mode, BookmarkPayload(true, true, true, true))
+    }
 
-        containerView.displayAs(LibrarySiteItemView.ItemType.FOLDER)
+    override fun bind(item: BookmarkNode, mode: BookmarkFragmentState.Mode, payload: BookmarkPayload) {
+        this.item = item
 
         setSelectionListeners(item, selectionHolder)
 
         if (!item.inRoots()) {
             setupMenu(item)
-            if (mode is BookmarkFragmentState.Mode.Selecting) {
+            if (payload.modeChanged) {
-                containerView.overflowView.hideAndDisable()
+                if (mode is BookmarkFragmentState.Mode.Selecting) {
-            } else {
+                    containerView.overflowView.hideAndDisable()
-                containerView.overflowView.showAndEnable()
+                } else {
+                    containerView.overflowView.showAndEnable()
+                }
             }
         } else {
             containerView.overflowView.visibility = View.GONE
         }
 
-        containerView.changeSelected(item in selectionHolder.selectedItems)
+        if (payload.selectedChanged) {
+            containerView.changeSelected(item in selectionHolder.selectedItems)
+        }
+
         containerView.iconView.setImageDrawable(
             AppCompatResources.getDrawable(
                 containerView.context,
@@ -63,6 +75,9 @@ class BookmarkFolderViewHolder(
                 )
             }
         )
-        containerView.titleView.text = item.title
+
+        if (payload.titleChanged) {
+            containerView.titleView.text = item.title
+        }
     }
 }

app/src/main/java/org/mozilla/fenix/library/bookmarks/viewholders/BookmarkItemViewHolder.kt

@@ -10,6 +10,7 @@ import org.mozilla.fenix.ext.showAndEnable
 import org.mozilla.fenix.library.LibrarySiteItemView
 import org.mozilla.fenix.library.SelectionHolder
 import org.mozilla.fenix.library.bookmarks.BookmarkFragmentState
+import org.mozilla.fenix.library.bookmarks.BookmarkPayload
 import org.mozilla.fenix.library.bookmarks.BookmarkViewInteractor
 
 /**
@@ -23,27 +24,46 @@ class BookmarkItemViewHolder(
 
     override var item: BookmarkNode? = null
 
+    init {
+        containerView.displayAs(LibrarySiteItemView.ItemType.SITE)
+    }
+
     override fun bind(
         item: BookmarkNode,
         mode: BookmarkFragmentState.Mode
     ) {
+        bind(item, mode, BookmarkPayload(true, true, true, true))
+    }
+
+    override fun bind(item: BookmarkNode, mode: BookmarkFragmentState.Mode, payload: BookmarkPayload) {
         this.item = item
 
-        containerView.displayAs(LibrarySiteItemView.ItemType.SITE)
-
-        if (mode is BookmarkFragmentState.Mode.Selecting) {
-            containerView.overflowView.hideAndDisable()
-        } else {
-            containerView.overflowView.showAndEnable()
-        }
         setupMenu(item)
-        containerView.titleView.text = if (item.title.isNullOrBlank()) item.url else item.title
+
-        containerView.urlView.text = item.url
+        if (payload.modeChanged) {
+            if (mode is BookmarkFragmentState.Mode.Selecting) {
+                containerView.overflowView.hideAndDisable()
+            } else {
+                containerView.overflowView.showAndEnable()
+            }
+        }
+
+        if (payload.selectedChanged) {
+            containerView.changeSelected(item in selectionHolder.selectedItems)
+        }
+
+        if (payload.titleChanged) {
+            containerView.titleView.text = if (item.title.isNullOrBlank()) item.url else item.title
+        } else if (payload.urlChanged && item.title.isNullOrBlank()) {
+            containerView.titleView.text = item.url
+        }
+
+        if (payload.urlChanged) {
+            containerView.urlView.text = item.url
+            setColorsAndIcons(item.url)
+        }
 
         setSelectionListeners(item, selectionHolder)
-
-        containerView.changeSelected(item in selectionHolder.selectedItems)
-        setColorsAndIcons(item.url)
     }
 
     private fun setColorsAndIcons(url: String?) {

app/src/main/java/org/mozilla/fenix/library/bookmarks/viewholders/BookmarkNodeViewHolder.kt

@@ -11,6 +11,7 @@ import org.mozilla.fenix.library.LibrarySiteItemView
 import org.mozilla.fenix.library.SelectionHolder
 import org.mozilla.fenix.library.bookmarks.BookmarkFragmentState
 import org.mozilla.fenix.library.bookmarks.BookmarkItemMenu
+import org.mozilla.fenix.library.bookmarks.BookmarkPayload
 import org.mozilla.fenix.library.bookmarks.BookmarkViewInteractor
 
 /**
@@ -28,6 +29,12 @@ abstract class BookmarkNodeViewHolder(
         mode: BookmarkFragmentState.Mode
     )
 
+    abstract fun bind(
+        item: BookmarkNode,
+        mode: BookmarkFragmentState.Mode,
+        payload: BookmarkPayload
+    )
+
     protected fun setSelectionListeners(item: BookmarkNode, selectionHolder: SelectionHolder<BookmarkNode>) {
         containerView.setSelectionInteractor(item, selectionHolder, interactor)
     }

app/src/main/java/org/mozilla/fenix/library/bookmarks/viewholders/BookmarkSeparatorViewHolder.kt

@@ -7,6 +7,7 @@ package org.mozilla.fenix.library.bookmarks.viewholders
 import mozilla.components.concept.storage.BookmarkNode
 import org.mozilla.fenix.library.LibrarySiteItemView
 import org.mozilla.fenix.library.bookmarks.BookmarkFragmentState
+import org.mozilla.fenix.library.bookmarks.BookmarkPayload
 import org.mozilla.fenix.library.bookmarks.BookmarkViewInteractor
 
 /**
@@ -27,4 +28,12 @@ class BookmarkSeparatorViewHolder(
         containerView.displayAs(LibrarySiteItemView.ItemType.SEPARATOR)
         setupMenu(item)
     }
+
+    override fun bind(
+        item: BookmarkNode,
+        mode: BookmarkFragmentState.Mode,
+        payload: BookmarkPayload
+    ) {
+        bind(item, mode)
+    }
 }