Java tutorial
/* * Copyright (C) 2014 Google Inc. * * 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.talkback.menurules; import android.view.Menu; import com.android.talkback.R; import android.annotation.TargetApi; import android.content.Context; import android.os.Build; import android.support.v4.view.accessibility.AccessibilityNodeInfoCompat; import android.support.v4.view.accessibility.AccessibilityNodeInfoCompat.AccessibilityActionCompat; import android.text.TextUtils; import android.view.MenuItem; import com.google.android.marvin.talkback.TalkBackService; import com.android.talkback.contextmenu.ContextMenuItem; import com.android.talkback.contextmenu.ContextMenuItemBuilder; import com.android.utils.AccessibilityNodeInfoUtils; import com.android.utils.PerformActionUtils; import java.util.LinkedList; import java.util.List; /** * Adds custom actions to the local context menu. */ @TargetApi(Build.VERSION_CODES.LOLLIPOP) public class RuleCustomAction implements NodeMenuRule { public static final int MIN_API_LEVEL = Build.VERSION_CODES.LOLLIPOP; @Override public boolean accept(TalkBackService service, AccessibilityNodeInfoCompat node) { List<AccessibilityActionCompat> actions = node.getActionList(); return actions != null && !actions.isEmpty(); } @Override public List<ContextMenuItem> getMenuItemsForNode(TalkBackService service, ContextMenuItemBuilder menuItemBuilder, AccessibilityNodeInfoCompat node) { List<ContextMenuItem> menu = new LinkedList<>(); recursivelyPopulateMenuItemsForNode(service, menuItemBuilder, node, menu); return menu; } /** * Populates a menu with the context menu items for a node, searching up its ancestor * hierarchy if the current node has no custom actions. */ private void recursivelyPopulateMenuItemsForNode(TalkBackService service, ContextMenuItemBuilder menuItemBuilder, AccessibilityNodeInfoCompat node, List<ContextMenuItem> menu) { if (node == null) { return; } for (AccessibilityActionCompat action : AccessibilityNodeInfoUtils.getCustomActions(node)) { CharSequence label = action.getLabel(); int id = action.getId(); if (TextUtils.isEmpty(label)) { continue; } ContextMenuItem item = menuItemBuilder.createMenuItem(service, Menu.NONE, id, Menu.NONE, label); item.setOnMenuItemClickListener(new CustomMenuItem(id, AccessibilityNodeInfoCompat.obtain(node))); item.setCheckable(false); menu.add(item); } if (menu.isEmpty()) { recursivelyPopulateMenuItemsForNode(service, menuItemBuilder, node.getParent(), menu); } } @Override public boolean canCollapseMenu() { return true; } @Override public CharSequence getUserFriendlyMenuName(Context context) { return context.getString(R.string.title_custom_action); } private static class CustomMenuItem implements MenuItem.OnMenuItemClickListener { final int mId; final AccessibilityNodeInfoCompat mNode; CustomMenuItem(int id, AccessibilityNodeInfoCompat node) { mId = id; mNode = node; } @Override public boolean onMenuItemClick(MenuItem item) { boolean ret = PerformActionUtils.performAction(mNode, mId); mNode.recycle(); return ret; } } }