1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
|
/*
* Copyright (C) 2008 The Android Open Source Project
*
* 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.launcher2;
import android.graphics.Rect;
/**
* Interface defining an object that can receive a drag.
*
*/
public interface DropTarget {
class DragObject {
public int x = -1;
public int y = -1;
/** X offset from the upper-left corner of the cell to where we touched. */
public int xOffset = -1;
/** Y offset from the upper-left corner of the cell to where we touched. */
public int yOffset = -1;
/** This indicates whether a drag is in final stages, either drop or cancel. It
* differentiates onDragExit, since this is called when the drag is ending, above
* the current drag target, or when the drag moves off the current drag object.
*/
public boolean dragComplete = false;
/** The view that moves around while you drag. */
public DragView dragView = null;
/** The data associated with the object being dragged */
public Object dragInfo = null;
/** Where the drag originated */
public DragSource dragSource = null;
/** Post drag animation runnable */
public Runnable postAnimationRunnable = null;
public DragObject() {
}
}
/**
* Used to temporarily disable certain drop targets
*
* @return boolean specifying whether this drop target is currently enabled
*/
boolean isDropEnabled();
/**
* Handle an object being dropped on the DropTarget
*
* @param source DragSource where the drag started
* @param x X coordinate of the drop location
* @param y Y coordinate of the drop location
* @param xOffset Horizontal offset with the object being dragged where the original
* touch happened
* @param yOffset Vertical offset with the object being dragged where the original
* touch happened
* @param dragView The DragView that's being dragged around on screen.
* @param dragInfo Data associated with the object being dragged
*
*/
void onDrop(DragObject dragObject);
void onDragEnter(DragObject dragObject);
void onDragOver(DragObject dragObject);
void onDragExit(DragObject dragObject);
/**
* Allows a DropTarget to delegate drag and drop events to another object.
*
* Most subclasses will should just return null from this method.
*
* @param source DragSource where the drag started
* @param x X coordinate of the drop location
* @param y Y coordinate of the drop location
* @param xOffset Horizontal offset with the object being dragged where the original
* touch happened
* @param yOffset Vertical offset with the object being dragged where the original
* touch happened
* @param dragView The DragView that's being dragged around on screen.
* @param dragInfo Data associated with the object being dragged
*
* @return The DropTarget to delegate to, or null to not delegate to another object.
*/
DropTarget getDropTargetDelegate(DragObject dragObject);
/**
* Check if a drop action can occur at, or near, the requested location.
* This will be called just before onDrop.
*
* @param source DragSource where the drag started
* @param x X coordinate of the drop location
* @param y Y coordinate of the drop location
* @param xOffset Horizontal offset with the object being dragged where the
* original touch happened
* @param yOffset Vertical offset with the object being dragged where the
* original touch happened
* @param dragView The DragView that's being dragged around on screen.
* @param dragInfo Data associated with the object being dragged
* @return True if the drop will be accepted, false otherwise.
*/
boolean acceptDrop(DragObject dragObject);
// These methods are implemented in Views
void getHitRect(Rect outRect);
void getLocationInDragLayer(int[] loc);
int getLeft();
int getTop();
}
|