| /* |
| * Copyright (C) 2017 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 com.android.documentsui.dirlist; |
| |
| import android.os.Bundle; |
| import android.view.View; |
| |
| import androidx.annotation.NonNull; |
| import androidx.annotation.Nullable; |
| import androidx.core.view.AccessibilityDelegateCompat; |
| import androidx.core.view.accessibility.AccessibilityNodeInfoCompat; |
| import androidx.core.view.accessibility.AccessibilityNodeInfoCompat.AccessibilityActionCompat; |
| import androidx.recyclerview.widget.RecyclerView; |
| import androidx.recyclerview.widget.RecyclerViewAccessibilityDelegate; |
| |
| import java.util.function.Function; |
| |
| /** |
| * Custom Accessibility Delegate for RecyclerViews to route click events on its child views to |
| * proper handlers, and to surface selection state to a11y events. |
| * <p> |
| * The majority of event handling isdone using TouchDetector instead of View.OnCLickListener, which |
| * most a11y services use to understand whether a particular view is clickable or not. Thus, we need |
| * to use a custom accessibility delegate to manually add ACTION_CLICK to clickable child views' |
| * accessibility node, and then correctly route these clicks done by a11y services to responsible |
| * click callbacks. |
| * <p> |
| * DocumentsUI uses {@link View#setActivated(boolean)} instead of {@link View#setSelected(boolean)} |
| * for marking a view as selected. We will surface that selection state to a11y services in this |
| * class. |
| */ |
| public class AccessibilityEventRouter extends RecyclerViewAccessibilityDelegate { |
| |
| private final ItemDelegate mItemDelegate; |
| private final Function<View, Boolean> mClickCallback; |
| private final Function<View, Boolean> mLongClickCallback; |
| |
| public AccessibilityEventRouter( |
| RecyclerView recyclerView, @NonNull Function<View, Boolean> clickCallback, |
| @Nullable Function<View, Boolean> longClickCallback) { |
| super(recyclerView); |
| mClickCallback = clickCallback; |
| mLongClickCallback = longClickCallback; |
| mItemDelegate = new ItemDelegate(this) { |
| @Override |
| public void onInitializeAccessibilityNodeInfo(View host, |
| AccessibilityNodeInfoCompat info) { |
| super.onInitializeAccessibilityNodeInfo(host, info); |
| final RecyclerView.ViewHolder holder = recyclerView.getChildViewHolder(host); |
| // if the viewHolder is a DocumentsHolder instance and the ItemDetails |
| // is null, it can't be clicked |
| if (holder instanceof DocumentHolder) { |
| if (((DocumentHolder)holder).getItemDetails() != null) { |
| addAction(info); |
| } |
| } else { |
| addAction(info); |
| } |
| info.setSelected(host.isActivated()); |
| } |
| |
| @Override |
| public boolean performAccessibilityAction(View host, int action, Bundle args) { |
| // We are only handling click events; route all other to default implementation |
| if (action == AccessibilityNodeInfoCompat.ACTION_CLICK) { |
| return mClickCallback.apply(host); |
| } else if (action == AccessibilityNodeInfoCompat.ACTION_LONG_CLICK |
| && mLongClickCallback != null) { |
| return mLongClickCallback.apply(host); |
| } |
| return super.performAccessibilityAction(host, action, args); |
| } |
| }; |
| } |
| |
| @Override |
| public AccessibilityDelegateCompat getItemDelegate() { |
| return mItemDelegate; |
| } |
| |
| private void addAction(AccessibilityNodeInfoCompat info) { |
| info.addAction(AccessibilityActionCompat.ACTION_CLICK); |
| if (mLongClickCallback != null) { |
| info.addAction(AccessibilityNodeInfoCompat.ACTION_LONG_CLICK); |
| } |
| } |
| } |