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 17 package com.android.launcher3.dragndrop; 18 19 import android.content.Context; 20 import android.view.DragEvent; 21 import android.view.MotionEvent; 22 import com.android.launcher3.DropTarget.DragObject; 23 import com.android.launcher3.Utilities; 24 25 /** 26 * Base class for driving a drag/drop operation. 27 */ 28 public abstract class DragDriver { 29 protected final EventListener mEventListener; 30 31 public interface EventListener { onDriverDragMove(float x, float y)32 void onDriverDragMove(float x, float y); onDriverDragExitWindow()33 void onDriverDragExitWindow(); onDriverDragEnd(float x, float y)34 void onDriverDragEnd(float x, float y); onDriverDragCancel()35 void onDriverDragCancel(); 36 } 37 DragDriver(EventListener eventListener)38 public DragDriver(EventListener eventListener) { 39 mEventListener = eventListener; 40 } 41 42 /** 43 * Handles ending of the DragView animation. 44 */ onDragViewAnimationEnd()45 public void onDragViewAnimationEnd() { } 46 onTouchEvent(MotionEvent ev)47 public boolean onTouchEvent(MotionEvent ev) { 48 final int action = ev.getAction(); 49 50 switch (action) { 51 case MotionEvent.ACTION_MOVE: 52 mEventListener.onDriverDragMove(ev.getX(), ev.getY()); 53 break; 54 case MotionEvent.ACTION_UP: 55 mEventListener.onDriverDragMove(ev.getX(), ev.getY()); 56 mEventListener.onDriverDragEnd(ev.getX(), ev.getY()); 57 break; 58 case MotionEvent.ACTION_CANCEL: 59 mEventListener.onDriverDragCancel(); 60 break; 61 } 62 63 return true; 64 } 65 onDragEvent(DragEvent event)66 public abstract boolean onDragEvent (DragEvent event); 67 68 onInterceptTouchEvent(MotionEvent ev)69 public boolean onInterceptTouchEvent(MotionEvent ev) { 70 final int action = ev.getAction(); 71 72 switch (action) { 73 case MotionEvent.ACTION_UP: 74 mEventListener.onDriverDragEnd(ev.getX(), ev.getY()); 75 break; 76 case MotionEvent.ACTION_CANCEL: 77 mEventListener.onDriverDragCancel(); 78 break; 79 } 80 81 return true; 82 } 83 create(Context context, DragController dragController, DragObject dragObject, DragOptions options)84 public static DragDriver create(Context context, DragController dragController, 85 DragObject dragObject, DragOptions options) { 86 if (Utilities.ATLEAST_NOUGAT && options.systemDndStartPoint != null) { 87 return new SystemDragDriver(dragController, context, dragObject); 88 } else { 89 return new InternalDragDriver(dragController); 90 } 91 } 92 } 93 94 /** 95 * Class for driving a system (i.e. framework) drag/drop operation. 96 */ 97 class SystemDragDriver extends DragDriver { 98 99 float mLastX = 0; 100 float mLastY = 0; 101 SystemDragDriver(DragController dragController, Context context, DragObject dragObject)102 SystemDragDriver(DragController dragController, Context context, DragObject dragObject) { 103 super(dragController); 104 } 105 106 @Override onTouchEvent(MotionEvent ev)107 public boolean onTouchEvent(MotionEvent ev) { 108 return false; 109 } 110 111 @Override onInterceptTouchEvent(MotionEvent ev)112 public boolean onInterceptTouchEvent(MotionEvent ev) { 113 return false; 114 } 115 116 @Override onDragEvent(DragEvent event)117 public boolean onDragEvent (DragEvent event) { 118 final int action = event.getAction(); 119 120 switch (action) { 121 case DragEvent.ACTION_DRAG_STARTED: 122 mLastX = event.getX(); 123 mLastY = event.getY(); 124 return true; 125 126 case DragEvent.ACTION_DRAG_ENTERED: 127 return true; 128 129 case DragEvent.ACTION_DRAG_LOCATION: 130 mLastX = event.getX(); 131 mLastY = event.getY(); 132 mEventListener.onDriverDragMove(event.getX(), event.getY()); 133 return true; 134 135 case DragEvent.ACTION_DROP: 136 mLastX = event.getX(); 137 mLastY = event.getY(); 138 mEventListener.onDriverDragMove(event.getX(), event.getY()); 139 mEventListener.onDriverDragEnd(mLastX, mLastY); 140 return true; 141 case DragEvent.ACTION_DRAG_EXITED: 142 mEventListener.onDriverDragExitWindow(); 143 return true; 144 145 case DragEvent.ACTION_DRAG_ENDED: 146 mEventListener.onDriverDragCancel(); 147 return true; 148 149 default: 150 return false; 151 } 152 } 153 } 154 155 /** 156 * Class for driving an internal (i.e. not using framework) drag/drop operation. 157 */ 158 class InternalDragDriver extends DragDriver { InternalDragDriver(DragController dragController)159 InternalDragDriver(DragController dragController) { 160 super(dragController); 161 } 162 163 @Override onDragEvent(DragEvent event)164 public boolean onDragEvent (DragEvent event) { return false; } 165 } 166