1 /*
2  * Copyright (C) 2017 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 
17 package com.android.systemui.recents.views.grid;
18 
19 import android.content.Context;
20 import android.graphics.Rect;
21 import android.util.AttributeSet;
22 import android.view.View;
23 
24 import android.view.ViewTreeObserver.OnGlobalFocusChangeListener;
25 import com.android.systemui.R;
26 import com.android.systemui.recents.model.TaskStack;
27 import com.android.systemui.recents.views.TaskStackView;
28 
29 public class TaskViewFocusFrame extends View implements OnGlobalFocusChangeListener {
30 
31     private TaskStackView mSv;
32     private TaskGridLayoutAlgorithm mTaskGridLayoutAlgorithm;
TaskViewFocusFrame(Context context)33     public TaskViewFocusFrame(Context context) {
34         this(context, null);
35     }
36 
TaskViewFocusFrame(Context context, AttributeSet attrs)37     public TaskViewFocusFrame(Context context, AttributeSet attrs) {
38         this(context, attrs, 0);
39     }
40 
TaskViewFocusFrame(Context context, AttributeSet attrs, int defStyleAttr)41     public TaskViewFocusFrame(Context context, AttributeSet attrs, int defStyleAttr) {
42         this(context, attrs, defStyleAttr, 0);
43     }
44 
TaskViewFocusFrame(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes)45     public TaskViewFocusFrame(Context context, AttributeSet attrs, int defStyleAttr,
46         int defStyleRes) {
47         super(context, attrs, defStyleAttr, defStyleRes);
48         setBackground(mContext.getDrawable(
49             R.drawable.recents_grid_task_view_focus_frame_background));
50         setFocusable(false);
51         hide();
52     }
53 
TaskViewFocusFrame(Context context, TaskStackView stackView, TaskGridLayoutAlgorithm taskGridLayoutAlgorithm)54     public TaskViewFocusFrame(Context context, TaskStackView stackView,
55         TaskGridLayoutAlgorithm taskGridLayoutAlgorithm) {
56         this(context);
57         mSv = stackView;
58         mTaskGridLayoutAlgorithm = taskGridLayoutAlgorithm;
59     }
60 
61     /**
62      * Measure the width and height of the focus frame according to the current grid task view size.
63      */
measure()64     public void measure() {
65         int thickness = mTaskGridLayoutAlgorithm.getFocusFrameThickness();
66         Rect rect = mTaskGridLayoutAlgorithm.getTaskGridRect();
67         measure(
68             MeasureSpec.makeMeasureSpec(rect.width() + thickness * 2, MeasureSpec.EXACTLY),
69             MeasureSpec.makeMeasureSpec(rect.height() + thickness * 2, MeasureSpec.EXACTLY));
70     }
71 
72     /**
73      * Layout the focus frame with its size.
74      */
layout()75     public void layout() {
76         layout(0, 0, getMeasuredWidth(), getMeasuredHeight());
77     }
78 
79     /**
80      * Update the current size of grid task view and the focus frame.
81      */
resize()82     public void resize() {
83         if (mSv.useGridLayout()) {
84             mTaskGridLayoutAlgorithm.updateTaskGridRect(mSv.getStack().getTaskCount());
85             measure();
86             requestLayout();
87         }
88     }
89 
90     /**
91      * Move the task view focus frame to surround the newly focused view. If it's {@code null} or
92      * it's not an instance of GridTaskView, we hide the focus frame.
93      * @param newFocus The newly focused view.
94      */
moveGridTaskViewFocus(View newFocus)95     public void moveGridTaskViewFocus(View newFocus) {
96         if (mSv.useGridLayout()) {
97             // The frame only shows up in the grid layout. It shouldn't show up in the stack
98             // layout including when we're in the split screen.
99             if (newFocus instanceof GridTaskView) {
100                 // If the focus goes to a GridTaskView, we show the frame and layout it.
101                 int[] location = new int[2];
102                 newFocus.getLocationInWindow(location);
103                 int thickness = mTaskGridLayoutAlgorithm.getFocusFrameThickness();
104                 setTranslationX(location[0] - thickness);
105                 setTranslationY(location[1] - thickness);
106                 show();
107             } else {
108                 // If focus goes to other views, we hide the frame.
109                 hide();
110             }
111         }
112     }
113 
114     @Override
onGlobalFocusChanged(View oldFocus, View newFocus)115     public void onGlobalFocusChanged(View oldFocus, View newFocus) {
116         if (!mSv.useGridLayout()) {
117             return;
118         }
119         if (newFocus == null) {
120             // We're going to touch mode, unset the focus.
121             moveGridTaskViewFocus(null);
122             return;
123         }
124         if (oldFocus == null) {
125             // We're returning from touch mode, set the focus to the previously focused task.
126             final TaskStack stack = mSv.getStack();
127             final int taskCount = stack.getTaskCount();
128             final int k = stack.indexOfTask(mSv.getFocusedTask());
129             final int taskIndexToFocus = k == -1 ? (taskCount - 1) : (k % taskCount);
130             mSv.setFocusedTask(taskIndexToFocus, false, true);
131         }
132     }
133 
show()134     private void show() {
135         setAlpha(1f);
136     }
137 
hide()138     private void hide() {
139         setAlpha(0f);
140     }
141 }
142