/*
|
* Copyright (C) 2008 The Android Open Source Project, Romain Guy
|
*
|
* 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.
|
*/
|
|
/*
|
* 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.ysvideo.zhibo.lib.common.drawable;
|
|
import android.graphics.Canvas;
|
import android.graphics.drawable.Drawable;
|
import android.os.SystemClock;
|
|
public class TransitionDrawable extends LayerDrawable implements Drawable.Callback {
|
|
/**
|
* 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 boolean mReverse;
|
private long mStartTimeMillis;
|
private int mFrom;
|
private int mTo;
|
private int mDuration;
|
private TransitionState mState;
|
|
public TransitionDrawable(Drawable... layers) {
|
this(new TransitionState(null, null), layers);
|
}
|
|
TransitionDrawable() {
|
this(new TransitionState(null, null));
|
}
|
|
private TransitionDrawable(TransitionState state) {
|
super(state);
|
mState = state;
|
}
|
|
private TransitionDrawable(TransitionState state, Drawable... layers) {
|
super(state, layers);
|
mState = state;
|
}
|
|
@Override
|
LayerState createConstantState(LayerState state) {
|
return new TransitionState((TransitionState) state, this);
|
}
|
|
/**
|
* 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;
|
mState.mAlpha = 0;
|
mState.mDuration = mDuration = durationMillis;
|
mReverse = false;
|
mTransitionState = TRANSITION_STARTING;
|
invalidateSelf();
|
}
|
|
/**
|
* Show only the first layer.
|
*/
|
public void resetTransition() {
|
mState.mAlpha = 0;
|
mTransitionState = TRANSITION_NONE;
|
invalidateSelf();
|
}
|
|
/**
|
* Reverses the transition, picking up where the transition currently is.
|
* If the transition is not currently running, this will start the transition
|
* with the specified duration. If the transition is already running, the last
|
* known duration will be used.
|
*
|
* @param duration The duration to use if no transition is running.
|
*/
|
public void reverseTransition(int duration) {
|
final long time = SystemClock.uptimeMillis();
|
// Animation is over
|
if (time - mStartTimeMillis > mState.mDuration) {
|
if (mState.mAlpha == 0) {
|
mFrom = 0;
|
mTo = 255;
|
mState.mAlpha = 0;
|
mReverse = false;
|
} else {
|
mFrom = 255;
|
mTo = 0;
|
mState.mAlpha = 255;
|
mReverse = true;
|
}
|
mDuration = mState.mDuration = duration;
|
mTransitionState = TRANSITION_STARTING;
|
invalidateSelf();
|
return;
|
}
|
|
mReverse = !mReverse;
|
mFrom = mState.mAlpha;
|
mTo = mReverse ? 0 : 255;
|
mDuration = (int) (mReverse ? time - mStartTimeMillis :
|
mState.mDuration - (time - mStartTimeMillis));
|
mTransitionState = TRANSITION_STARTING;
|
}
|
|
@Override
|
public void draw(Canvas canvas) {
|
boolean done = true;
|
final TransitionState state = mState;
|
|
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);
|
state.mAlpha = (int) (mFrom + (mTo - mFrom) * normalized);
|
}
|
break;
|
}
|
|
final int alpha = state.mAlpha;
|
final boolean crossFade = state.mCrossFade;
|
final Rec[] array = mLayerState.mArray;
|
Drawable d;
|
|
d = array[0].mDrawable;
|
if (crossFade) {
|
d.setAlpha(255 - alpha);
|
}
|
d.draw(canvas);
|
if (crossFade) {
|
d.setAlpha(0xFF);
|
}
|
|
if (alpha > 0) {
|
d = array[1].mDrawable;
|
d.setAlpha(alpha);
|
d.draw(canvas);
|
d.setAlpha(0xFF);
|
}
|
|
if (!done) {
|
invalidateSelf();
|
}
|
}
|
|
/**
|
* Enables or disables the cross fade of the drawables. When cross fade
|
* is disabled, the first drawable is always drawn opaque. With cross
|
* fade enabled, the first drawable is drawn with the opposite alpha of
|
* the second drawable.
|
*
|
* @param enabled True to enable cross fading, false otherwise.
|
*/
|
public void setCrossFadeEnabled(boolean enabled) {
|
mState.mCrossFade = enabled;
|
}
|
|
/**
|
* Indicates whether the cross fade is enabled for this transition.
|
*
|
* @return True if cross fading is enabled, false otherwise.
|
*/
|
public boolean isCrossFadeEnabled() {
|
return mState.mCrossFade;
|
}
|
|
static class TransitionState extends LayerState {
|
int mAlpha = 0;
|
int mDuration;
|
boolean mCrossFade;
|
|
TransitionState(TransitionState orig, TransitionDrawable owner) {
|
super(orig, owner);
|
}
|
|
@Override
|
public Drawable newDrawable() {
|
return new TransitionDrawable(this);
|
}
|
|
@Override
|
public int getChangingConfigurations() {
|
return mChangingConfigurations;
|
}
|
}
|
}
|