RecentsViewTouchHandler.java revision 53ec42cb17693b2d631746e1e5d31021a3359163 
1/*
2 * Copyright (C) 2014 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.systemui.recents.views;
18
19import android.content.res.Configuration;
20import android.graphics.Point;
21import android.view.MotionEvent;
22import com.android.systemui.recents.Recents;
23import com.android.systemui.recents.RecentsConfiguration;
24import com.android.systemui.recents.events.EventBus;
25import com.android.systemui.recents.events.ui.dragndrop.DragDockStateChangedEvent;
26import com.android.systemui.recents.events.ui.dragndrop.DragEndEvent;
27import com.android.systemui.recents.events.ui.dragndrop.DragStartEvent;
28import com.android.systemui.recents.misc.ReferenceCountedTrigger;
29import com.android.systemui.recents.model.Task;
30import com.android.systemui.recents.model.TaskStack;
31
32
33/**
34 * Represents the dock regions for each orientation.
35 */
36class DockRegion {
37    public static TaskStack.DockState[] PHONE_LANDSCAPE = {
38            // We only allow docking to the left for now on small devices
39            TaskStack.DockState.LEFT
40    };
41    public static TaskStack.DockState[] PHONE_PORTRAIT = {
42            // We only allow docking to the top for now on small devices
43            TaskStack.DockState.TOP
44    };
45    public static TaskStack.DockState[] TABLET_LANDSCAPE = {
46            TaskStack.DockState.LEFT,
47            TaskStack.DockState.RIGHT
48    };
49    public static TaskStack.DockState[] TABLET_PORTRAIT = PHONE_PORTRAIT;
50}
51
52/**
53 * Handles touch events for a RecentsView.
54 */
55class RecentsViewTouchHandler {
56
57    private RecentsView mRv;
58
59    private Task mDragTask;
60    private TaskView mTaskView;
61    private DragView mDragView;
62
63    private Point mDownPos = new Point();
64    private boolean mDragging;
65    private TaskStack.DockState mLastDockState = TaskStack.DockState.NONE;
66
67    public RecentsViewTouchHandler(RecentsView rv) {
68        mRv = rv;
69    }
70
71    /**
72     * Returns the preferred dock states for the current orientation.
73     */
74    public TaskStack.DockState[] getDockStatesForCurrentOrientation() {
75        boolean isLandscape = mRv.getResources().getConfiguration().orientation ==
76                Configuration.ORIENTATION_LANDSCAPE;
77        RecentsConfiguration config = Recents.getConfiguration();
78        TaskStack.DockState[] dockStates = isLandscape ?
79                (config.isLargeScreen ? DockRegion.TABLET_LANDSCAPE : DockRegion.PHONE_LANDSCAPE) :
80                (config.isLargeScreen ? DockRegion.TABLET_PORTRAIT : DockRegion.PHONE_PORTRAIT);
81        return dockStates;
82    }
83
84    /** Touch preprocessing for handling below */
85    public boolean onInterceptTouchEvent(MotionEvent ev) {
86        handleTouchEvent(ev);
87        return mDragging;
88    }
89
90    /** Handles touch events once we have intercepted them */
91    public boolean onTouchEvent(MotionEvent ev) {
92        handleTouchEvent(ev);
93        return mDragging;
94    }
95
96    /**** Events ****/
97
98    public final void onBusEvent(DragStartEvent event) {
99        mRv.getParent().requestDisallowInterceptTouchEvent(true);
100        mDragging = true;
101        mDragTask = event.task;
102        mTaskView = event.taskView;
103        mDragView = event.dragView;
104
105        float x = mDownPos.x - mDragView.getTopLeftOffset().x;
106        float y = mDownPos.y - mDragView.getTopLeftOffset().y;
107        mDragView.setTranslationX(x);
108        mDragView.setTranslationY(y);
109    }
110
111    public final void onBusEvent(DragEndEvent event) {
112        mDragging = false;
113        mDragTask = null;
114        mTaskView = null;
115        mDragView = null;
116        mLastDockState = TaskStack.DockState.NONE;
117    }
118
119    /**
120     * Handles dragging touch events
121     * @param ev
122     */
123    private void handleTouchEvent(MotionEvent ev) {
124        boolean isLandscape = mRv.getResources().getConfiguration().orientation ==
125                Configuration.ORIENTATION_LANDSCAPE;
126        int action = ev.getAction();
127        switch (action & MotionEvent.ACTION_MASK) {
128            case MotionEvent.ACTION_DOWN:
129                mDownPos.set((int) ev.getX(), (int) ev.getY());
130                break;
131            case MotionEvent.ACTION_MOVE: {
132                if (mDragging) {
133                    int width = mRv.getMeasuredWidth();
134                    int height = mRv.getMeasuredHeight();
135                    float evX = ev.getX();
136                    float evY = ev.getY();
137                    float x = evX - mDragView.getTopLeftOffset().x;
138                    float y = evY - mDragView.getTopLeftOffset().y;
139
140                    // Update the dock state
141                    TaskStack.DockState[] dockStates = getDockStatesForCurrentOrientation();
142                    TaskStack.DockState foundDockState = TaskStack.DockState.NONE;
143                    for (int i = dockStates.length - 1; i >= 0; i--) {
144                        TaskStack.DockState state = dockStates[i];
145                        if (state.touchAreaContainsPoint(width, height, evX, evY)) {
146                            foundDockState = state;
147                            break;
148                        }
149                    }
150                    if (mLastDockState != foundDockState) {
151                        mLastDockState = foundDockState;
152                        EventBus.getDefault().send(new DragDockStateChangedEvent(mDragTask,
153                                foundDockState));
154                    }
155
156                    mDragView.setTranslationX(x);
157                    mDragView.setTranslationY(y);
158                }
159                break;
160            }
161            case MotionEvent.ACTION_UP:
162            case MotionEvent.ACTION_CANCEL: {
163                if (mDragging) {
164                    ReferenceCountedTrigger postAnimationTrigger = new ReferenceCountedTrigger(
165                            mRv.getContext(), null, null, null);
166                    postAnimationTrigger.increment();
167                    EventBus.getDefault().send(new DragEndEvent(mDragTask, mTaskView, mDragView,
168                            mLastDockState, postAnimationTrigger));
169                    postAnimationTrigger.decrement();
170                    break;
171                }
172            }
173        }
174    }
175}
176