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
158
159
160
161
162
163
164
165
166
167
168
169
170
171
|
/*
* Copyright (C) 2016 Cyanogen, Inc.
* Copyright (C) 2016 The CyanogenMod 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 org.cyanogenmod.theme.chooser;
import android.graphics.Canvas;
import android.graphics.drawable.Drawable;
import android.graphics.drawable.LayerDrawable;
import android.os.SystemClock;
/**
* An extension of LayerDrawables that is intended to cross-fade between
* the first and second layer. To start the transition, call {@link #startTransition(int)}. To
* display just the first layer, call {@link #resetTransition()}.
* <p>
* It can be defined in an XML file with the <code><transition></code> element.
* Each Drawable in the transition is defined in a nested <code><item></code>. For more
* information, see the guide to <a
* href="{@docRoot}guide/topics/resources/drawable-resource.html">Drawable Resources</a>.</p>
*
* @attr ref android.R.styleable#LayerDrawableItem_left
* @attr ref android.R.styleable#LayerDrawableItem_top
* @attr ref android.R.styleable#LayerDrawableItem_right
* @attr ref android.R.styleable#LayerDrawableItem_bottom
* @attr ref android.R.styleable#LayerDrawableItem_drawable
* @attr ref android.R.styleable#LayerDrawableItem_id
*
*/
public class IconTransitionDrawable extends LayerDrawable {
/**
* A transition is about to start.
*/
private static final int TRANSITION_STARTING = 0;
/**
* The transition has started and the animation is in progress
*/
private static final int TRANSITION_RUNNING = 1;
/**
* No transition will be applied
*/
private static final int TRANSITION_NONE = 2;
/**
* The current state of the transition. One of {@link #TRANSITION_STARTING},
* {@link #TRANSITION_RUNNING} and {@link #TRANSITION_NONE}
*/
private int mTransitionState = TRANSITION_NONE;
private long mStartTimeMillis;
private int mFrom;
private int mTo;
private int mDuration;
private int mAlpha = 0;
private float mFromScale;
private float mToScale;
/**
* Create a new transition drawable with the specified list of layers. At least
* 2 layers are required for this drawable to work properly.
*/
public IconTransitionDrawable(Drawable[] layers) {
super(layers);
}
/**
* Begin the second layer on top of the first layer.
*
* @param durationMillis The length of the transition in milliseconds
*/
public void startTransition(int durationMillis) {
mFrom = 0;
mTo = 255;
mAlpha = 0;
mFromScale = 0f;
mToScale = 1.0f;
mDuration = durationMillis;
mTransitionState = TRANSITION_STARTING;
invalidateSelf();
}
/**
* Show only the first layer.
*/
public void resetTransition() {
mAlpha = 0;
mTransitionState = TRANSITION_NONE;
invalidateSelf();
}
@Override
public void draw(Canvas canvas) {
boolean done = true;
float scale = 0f;
switch (mTransitionState) {
case TRANSITION_STARTING:
mStartTimeMillis = SystemClock.uptimeMillis();
done = false;
mTransitionState = TRANSITION_RUNNING;
break;
case TRANSITION_RUNNING:
if (mStartTimeMillis >= 0) {
float normalized = (float)
(SystemClock.uptimeMillis() - mStartTimeMillis) / mDuration;
done = normalized >= 1.0f;
normalized = Math.min(normalized, 1.0f);
mAlpha = (int) (mFrom + (mTo - mFrom) * normalized);
scale = mFromScale + (mToScale - mFromScale) * normalized;
}
break;
}
final int alpha = mAlpha;
if (done) {
// the setAlpha() calls below trigger invalidation and redraw. If we're done, just draw
// the appropriate drawable[s] and return
if (alpha == 0) {
getDrawable(0).draw(canvas);
}
if (alpha == 0xFF) {
getDrawable(1).draw(canvas);
}
return;
}
Drawable d;
d = getDrawable(0);
d.setAlpha(255 - alpha);
int cx = getIntrinsicWidth() / 2;
int cy = getIntrinsicHeight() / 2;
canvas.save();
canvas.scale(1.0f - scale, 1.0f - scale, cx, cy);
d.draw(canvas);
canvas.restore();
d.setAlpha(0xFF);
if (alpha > 0) {
d = getDrawable(1);
d.setAlpha(alpha);
canvas.save();
canvas.scale(scale, scale, cx, cy);
d.draw(canvas);
canvas.restore();
d.setAlpha(0xFF);
}
if (!done) {
invalidateSelf();
}
}
}
|
