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
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
|
/*
* Copyright (C) 2014 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 android.view;
import android.graphics.Canvas;
import android.graphics.Matrix;
import android.widget.FrameLayout;
/**
* This view draws another View in an Overlay without changing the parent. It will not be drawn
* by its parent because its visibility is set to INVISIBLE, but will be drawn
* here using its render node. When the GhostView is set to INVISIBLE, the View it is
* shadowing will become VISIBLE and when the GhostView becomes VISIBLE, the shadowed
* view becomes INVISIBLE.
* @hide
*/
public class GhostView extends View {
private final View mView;
private int mReferences;
private GhostView(View view) {
super(view.getContext());
mView = view;
mView.mGhostView = this;
final ViewGroup parent = (ViewGroup) mView.getParent();
setGhostedVisibility(View.INVISIBLE);
parent.mRecreateDisplayList = true;
parent.getDisplayList();
}
@Override
protected void onDraw(Canvas canvas) {
if (canvas instanceof HardwareCanvas) {
HardwareCanvas hwCanvas = (HardwareCanvas) canvas;
mView.mRecreateDisplayList = true;
RenderNode renderNode = mView.getDisplayList();
if (renderNode.isValid()) {
hwCanvas.drawRenderNode(renderNode);
}
}
}
public void setMatrix(Matrix matrix) {
mRenderNode.setAnimationMatrix(matrix);
}
@Override
public void setVisibility(@Visibility int visibility) {
super.setVisibility(visibility);
if (mView.mGhostView == this) {
int inverseVisibility = (visibility == View.VISIBLE) ? View.INVISIBLE : View.VISIBLE;
setGhostedVisibility(inverseVisibility);
}
}
private void setGhostedVisibility(int visibility) {
mView.mViewFlags = (mView.mViewFlags & ~View.VISIBILITY_MASK) | visibility;
}
@Override
protected void onDetachedFromWindow() {
super.onDetachedFromWindow();
setGhostedVisibility(View.VISIBLE);
mView.mGhostView = null;
final ViewGroup parent = (ViewGroup) mView.getParent();
if (parent != null) {
parent.mRecreateDisplayList = true;
parent.getDisplayList();
}
}
public static void calculateMatrix(View view, ViewGroup host, Matrix matrix) {
ViewGroup parent = (ViewGroup) view.getParent();
matrix.reset();
parent.transformMatrixToGlobal(matrix);
matrix.preTranslate(-parent.getScrollX(), -parent.getScrollY());
host.transformMatrixToLocal(matrix);
}
public static GhostView addGhost(View view, ViewGroup viewGroup, Matrix matrix) {
if (!(view.getParent() instanceof ViewGroup)) {
throw new IllegalArgumentException("Ghosted views must be parented by a ViewGroup");
}
ViewGroupOverlay overlay = viewGroup.getOverlay();
ViewOverlay.OverlayViewGroup overlayViewGroup = overlay.mOverlayViewGroup;
GhostView ghostView = view.mGhostView;
int previousRefCount = 0;
if (ghostView != null) {
View oldParent = (View) ghostView.getParent();
ViewGroup oldGrandParent = (ViewGroup) oldParent.getParent();
if (oldGrandParent != overlayViewGroup) {
previousRefCount = ghostView.mReferences;
oldGrandParent.removeView(oldParent);
ghostView = null;
}
}
if (ghostView == null) {
if (matrix == null) {
matrix = new Matrix();
calculateMatrix(view, viewGroup, matrix);
}
ghostView = new GhostView(view);
ghostView.setMatrix(matrix);
FrameLayout parent = new FrameLayout(view.getContext());
parent.setClipChildren(false);
copySize(viewGroup, parent);
copySize(viewGroup, ghostView);
parent.addView(ghostView);
overlay.add(parent);
ghostView.mReferences = previousRefCount;
} else if (matrix != null) {
ghostView.setMatrix(matrix);
}
ghostView.mReferences++;
return ghostView;
}
public static GhostView addGhost(View view, ViewGroup viewGroup) {
return addGhost(view, viewGroup, null);
}
public static void removeGhost(View view) {
GhostView ghostView = view.mGhostView;
if (ghostView != null) {
ghostView.mReferences--;
if (ghostView.mReferences == 0) {
ViewGroup parent = (ViewGroup) ghostView.getParent();
ViewGroup grandParent = (ViewGroup) parent.getParent();
grandParent.removeView(parent);
}
}
}
public static GhostView getGhost(View view) {
return view.mGhostView;
}
private static void copySize(View from, View to) {
to.setLeft(0);
to.setTop(0);
to.setRight(from.getWidth());
to.setBottom(from.getHeight());
}
}
|
