1/*
2 * Copyright (C) 2015 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.android.launcher3.accessibility;
18
19import android.annotation.TargetApi;
20import android.content.Context;
21import android.os.Build;
22import android.os.Bundle;
23import android.util.SparseArray;
24import android.view.View;
25import android.view.View.AccessibilityDelegate;
26import android.view.accessibility.AccessibilityNodeInfo;
27import android.view.accessibility.AccessibilityNodeInfo.AccessibilityAction;
28import com.android.launcher3.R;
29import com.android.launcher3.Utilities;
30import com.android.launcher3.Workspace;
31
32@TargetApi(Build.VERSION_CODES.LOLLIPOP)
33public class OverviewScreenAccessibilityDelegate extends AccessibilityDelegate {
34
35    private static final int MOVE_BACKWARD = R.id.action_move_screen_backwards;
36    private static final int MOVE_FORWARD = R.id.action_move_screen_forwards;
37
38    private final SparseArray<AccessibilityAction> mActions = new SparseArray<>();
39    private final Workspace mWorkspace;
40
41    public OverviewScreenAccessibilityDelegate(Workspace workspace) {
42        mWorkspace = workspace;
43
44        Context context = mWorkspace.getContext();
45        boolean isRtl = Utilities.isRtl(context.getResources());
46        mActions.put(MOVE_BACKWARD, new AccessibilityAction(MOVE_BACKWARD,
47                context.getText(isRtl ? R.string.action_move_screen_right :
48                    R.string.action_move_screen_left)));
49        mActions.put(MOVE_FORWARD, new AccessibilityAction(MOVE_FORWARD,
50                context.getText(isRtl ? R.string.action_move_screen_left :
51                    R.string.action_move_screen_right)));
52    }
53
54    @Override
55    public boolean performAccessibilityAction(View host, int action, Bundle args) {
56        if (host != null) {
57            if (action == AccessibilityNodeInfo.ACTION_ACCESSIBILITY_FOCUS ) {
58                int index = mWorkspace.indexOfChild(host);
59                mWorkspace.setCurrentPage(index);
60            } else if (action == MOVE_FORWARD) {
61                movePage(mWorkspace.indexOfChild(host) + 1, host);
62                return true;
63            } else if (action == MOVE_BACKWARD) {
64                movePage(mWorkspace.indexOfChild(host) - 1, host);
65                return true;
66            }
67        }
68
69        return super.performAccessibilityAction(host, action, args);
70    }
71
72    private void movePage(int finalIndex, View view) {
73        mWorkspace.onStartReordering();
74        mWorkspace.removeView(view);
75        mWorkspace.addView(view, finalIndex);
76        mWorkspace.onEndReordering();
77        mWorkspace.announceForAccessibility(mWorkspace.getContext().getText(R.string.screen_moved));
78
79        mWorkspace.updateAccessibilityFlags();
80        view.performAccessibilityAction(AccessibilityNodeInfo.ACTION_ACCESSIBILITY_FOCUS, null);
81    }
82
83    @Override
84    public void onInitializeAccessibilityNodeInfo(View host, AccessibilityNodeInfo info) {
85        super.onInitializeAccessibilityNodeInfo(host, info);
86
87        int index = mWorkspace.indexOfChild(host);
88        if (index < mWorkspace.getChildCount() - 1) {
89            info.addAction(mActions.get(MOVE_FORWARD));
90        }
91        if (index > mWorkspace.numCustomPages()) {
92            info.addAction(mActions.get(MOVE_BACKWARD));
93        }
94    }
95}
96