| /* |
| * Copyright 2018 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package androidx.recyclerview.widget; |
| |
| import android.os.Bundle; |
| import android.view.View; |
| import android.view.ViewGroup; |
| import android.view.accessibility.AccessibilityEvent; |
| |
| import androidx.annotation.NonNull; |
| import androidx.annotation.Nullable; |
| import androidx.core.view.AccessibilityDelegateCompat; |
| import androidx.core.view.ViewCompat; |
| import androidx.core.view.accessibility.AccessibilityNodeInfoCompat; |
| import androidx.core.view.accessibility.AccessibilityNodeProviderCompat; |
| |
| import java.util.Map; |
| import java.util.WeakHashMap; |
| |
| /** |
| * The AccessibilityDelegate used by RecyclerView. |
| * <p> |
| * This class handles basic accessibility actions and delegates them to LayoutManager. |
| */ |
| public class RecyclerViewAccessibilityDelegate extends AccessibilityDelegateCompat { |
| final RecyclerView mRecyclerView; |
| private final ItemDelegate mItemDelegate; |
| |
| |
| public RecyclerViewAccessibilityDelegate(@NonNull RecyclerView recyclerView) { |
| mRecyclerView = recyclerView; |
| AccessibilityDelegateCompat itemDelegate = getItemDelegate(); |
| if (itemDelegate != null && itemDelegate instanceof ItemDelegate) { |
| mItemDelegate = (ItemDelegate) itemDelegate; |
| } else { |
| mItemDelegate = new ItemDelegate(this); |
| } |
| } |
| |
| boolean shouldIgnore() { |
| return mRecyclerView.hasPendingAdapterUpdates(); |
| } |
| |
| @Override |
| public boolean performAccessibilityAction(View host, int action, Bundle args) { |
| if (super.performAccessibilityAction(host, action, args)) { |
| return true; |
| } |
| if (!shouldIgnore() && mRecyclerView.getLayoutManager() != null) { |
| return mRecyclerView.getLayoutManager().performAccessibilityAction(action, args); |
| } |
| |
| return false; |
| } |
| |
| @Override |
| public void onInitializeAccessibilityNodeInfo(View host, AccessibilityNodeInfoCompat info) { |
| super.onInitializeAccessibilityNodeInfo(host, info); |
| if (!shouldIgnore() && mRecyclerView.getLayoutManager() != null) { |
| mRecyclerView.getLayoutManager().onInitializeAccessibilityNodeInfo(info); |
| } |
| } |
| |
| @Override |
| public void onInitializeAccessibilityEvent(View host, AccessibilityEvent event) { |
| super.onInitializeAccessibilityEvent(host, event); |
| if (host instanceof RecyclerView && !shouldIgnore()) { |
| RecyclerView rv = (RecyclerView) host; |
| if (rv.getLayoutManager() != null) { |
| rv.getLayoutManager().onInitializeAccessibilityEvent(event); |
| } |
| } |
| } |
| |
| /** |
| * Gets the AccessibilityDelegate for an individual item in the RecyclerView. |
| * A basic item delegate is provided by default, but you can override this |
| * method to provide a custom per-item delegate. |
| * For now, returning an {@code AccessibilityDelegateCompat} as opposed to an |
| * {@code ItemDelegate} will prevent use of the {@code ViewCompat} accessibility API on |
| * item views. |
| */ |
| @NonNull |
| public AccessibilityDelegateCompat getItemDelegate() { |
| return mItemDelegate; |
| } |
| |
| /** |
| * The default implementation of accessibility delegate for the individual items of the |
| * RecyclerView. |
| * <p> |
| * If you are overriding {@code RecyclerViewAccessibilityDelegate#getItemDelegate()} but still |
| * want to keep some default behavior, you can create an instance of this class and delegate to |
| * the parent as necessary. |
| */ |
| public static class ItemDelegate extends AccessibilityDelegateCompat { |
| final RecyclerViewAccessibilityDelegate mRecyclerViewDelegate; |
| private Map<View, AccessibilityDelegateCompat> mOriginalItemDelegates = new WeakHashMap<>(); |
| |
| /** |
| * Creates an item delegate for the given {@code RecyclerViewAccessibilityDelegate}. |
| * |
| * @param recyclerViewDelegate The parent RecyclerView's accessibility delegate. |
| */ |
| public ItemDelegate(@NonNull RecyclerViewAccessibilityDelegate recyclerViewDelegate) { |
| mRecyclerViewDelegate = recyclerViewDelegate; |
| } |
| |
| /** |
| * Saves a reference to the original delegate of the itemView so that it's behavior can be |
| * combined with the ItemDelegate's behavior. |
| */ |
| void saveOriginalDelegate(View itemView) { |
| AccessibilityDelegateCompat delegate = ViewCompat.getAccessibilityDelegate(itemView); |
| if (delegate != null && delegate != this) { |
| mOriginalItemDelegates.put(itemView, delegate); |
| } |
| } |
| |
| /** |
| * @return The delegate associated with itemView before the view was bound. |
| */ |
| AccessibilityDelegateCompat getAndRemoveOriginalDelegateForItem(View itemView) { |
| return mOriginalItemDelegates.remove(itemView); |
| } |
| |
| @Override |
| public void onInitializeAccessibilityNodeInfo(View host, AccessibilityNodeInfoCompat info) { |
| if (!mRecyclerViewDelegate.shouldIgnore() |
| && mRecyclerViewDelegate.mRecyclerView.getLayoutManager() != null) { |
| mRecyclerViewDelegate.mRecyclerView.getLayoutManager() |
| .onInitializeAccessibilityNodeInfoForItem(host, info); |
| AccessibilityDelegateCompat originalDelegate = mOriginalItemDelegates.get(host); |
| if (originalDelegate != null) { |
| originalDelegate.onInitializeAccessibilityNodeInfo(host, info); |
| } else { |
| super.onInitializeAccessibilityNodeInfo(host, info); |
| } |
| } else { |
| super.onInitializeAccessibilityNodeInfo(host, info); |
| } |
| } |
| |
| @Override |
| public boolean performAccessibilityAction(View host, int action, Bundle args) { |
| if (!mRecyclerViewDelegate.shouldIgnore() |
| && mRecyclerViewDelegate.mRecyclerView.getLayoutManager() != null) { |
| AccessibilityDelegateCompat originalDelegate = mOriginalItemDelegates.get(host); |
| if (originalDelegate != null) { |
| if (originalDelegate.performAccessibilityAction(host, action, args)) { |
| return true; |
| } |
| } else if (super.performAccessibilityAction(host, action, args)) { |
| return true; |
| } |
| return mRecyclerViewDelegate.mRecyclerView.getLayoutManager() |
| .performAccessibilityActionForItem(host, action, args); |
| } else { |
| return super.performAccessibilityAction(host, action, args); |
| } |
| } |
| |
| @Override |
| public void sendAccessibilityEvent(@NonNull View host, int eventType) { |
| AccessibilityDelegateCompat originalDelegate = mOriginalItemDelegates.get(host); |
| if (originalDelegate != null) { |
| originalDelegate.sendAccessibilityEvent(host, eventType); |
| } else { |
| super.sendAccessibilityEvent(host, eventType); |
| } |
| } |
| |
| @Override |
| public void sendAccessibilityEventUnchecked(@NonNull View host, |
| @NonNull AccessibilityEvent event) { |
| AccessibilityDelegateCompat originalDelegate = mOriginalItemDelegates.get(host); |
| if (originalDelegate != null) { |
| originalDelegate.sendAccessibilityEventUnchecked(host, event); |
| } else { |
| super.sendAccessibilityEventUnchecked(host, event); |
| } |
| } |
| |
| @Override |
| public boolean dispatchPopulateAccessibilityEvent(@NonNull View host, |
| @NonNull AccessibilityEvent event) { |
| AccessibilityDelegateCompat originalDelegate = mOriginalItemDelegates.get(host); |
| if (originalDelegate != null) { |
| return originalDelegate.dispatchPopulateAccessibilityEvent(host, event); |
| } else { |
| return super.dispatchPopulateAccessibilityEvent(host, event); |
| } |
| } |
| |
| @Override |
| public void onPopulateAccessibilityEvent(@NonNull View host, |
| @NonNull AccessibilityEvent event) { |
| AccessibilityDelegateCompat originalDelegate = mOriginalItemDelegates.get(host); |
| if (originalDelegate != null) { |
| originalDelegate.onPopulateAccessibilityEvent(host, event); |
| } else { |
| super.onPopulateAccessibilityEvent(host, event); |
| } |
| } |
| |
| @Override |
| public void onInitializeAccessibilityEvent(@NonNull View host, |
| @NonNull AccessibilityEvent event) { |
| AccessibilityDelegateCompat originalDelegate = mOriginalItemDelegates.get(host); |
| if (originalDelegate != null) { |
| originalDelegate.onInitializeAccessibilityEvent(host, event); |
| } else { |
| super.onInitializeAccessibilityEvent(host, event); |
| } |
| } |
| |
| @Override |
| public boolean onRequestSendAccessibilityEvent(@NonNull ViewGroup host, |
| @NonNull View child, @NonNull AccessibilityEvent event) { |
| AccessibilityDelegateCompat originalDelegate = mOriginalItemDelegates.get(host); |
| if (originalDelegate != null) { |
| return originalDelegate.onRequestSendAccessibilityEvent(host, child, event); |
| } else { |
| return super.onRequestSendAccessibilityEvent(host, child, event); |
| } |
| } |
| |
| @Override |
| @Nullable |
| public AccessibilityNodeProviderCompat getAccessibilityNodeProvider(@NonNull View host) { |
| AccessibilityDelegateCompat originalDelegate = mOriginalItemDelegates.get(host); |
| if (originalDelegate != null) { |
| return originalDelegate.getAccessibilityNodeProvider(host); |
| } else { |
| return super.getAccessibilityNodeProvider(host); |
| } |
| } |
| } |
| } |
| |