static float getAnimatedFraction(ValueAnimator animator) {
float fraction =
animator.getDuration() > 0
? ((float) animator.getCurrentPlayTime()) / animator.getDuration()
: 0f;
fraction = min(fraction, 1f);
fraction = animator.getInterpolator().getInterpolation(fraction);
return fraction;
}
public void onAnimationUpdate(final ValueAnimator animation) {
final long currentTime = System.currentTimeMillis();
if (mStartTime == -1) {
mStartFrame = sGlobalFrameCounter;
mStartTime = currentTime;
}
final long currentPlayTime = animation.getCurrentPlayTime();
boolean isFinalFrame = Float.compare(1f, animation.getAnimatedFraction()) == 0;
if (!mHandlingOnAnimationUpdate
&& sVisible
&&
// If the current play time exceeds the duration, or the animated fraction is 1,
// the animation will get finished, even if we call setCurrentPlayTime -- therefore
// don't adjust the animation in that case
currentPlayTime < animation.getDuration()
&& !isFinalFrame) {
mHandlingOnAnimationUpdate = true;
long frameNum = sGlobalFrameCounter - mStartFrame;
// If we haven't drawn our first frame, reset the time to t = 0
// (give up after MAX_DELAY ms of waiting though - might happen, for example, if we
// are no longer in the foreground and no frames are being rendered ever)
if (frameNum == 0 && currentTime < mStartTime + MAX_DELAY && currentPlayTime > 0) {
// The first frame on animations doesn't always trigger an invalidate...
// force an invalidate here to make sure the animation continues to advance
mTarget.getRootView().invalidate();
animation.setCurrentPlayTime(0);
// For the second frame, if the first frame took more than 16ms,
// adjust the start time and pretend it took only 16ms anyway. This
// prevents a large jump in the animation due to an expensive first frame
} else if (frameNum == 1
&& currentTime < mStartTime + MAX_DELAY
&& !mAdjustedSecondFrameTime
&& currentTime > mStartTime + IDEAL_FRAME_DURATION
&& currentPlayTime > IDEAL_FRAME_DURATION) {
animation.setCurrentPlayTime(IDEAL_FRAME_DURATION);
mAdjustedSecondFrameTime = true;
} else {
if (frameNum > 1) {
mTarget.post(
new Runnable() {
public void run() {
animation.removeUpdateListener(FirstFrameAnimatorHelper.this);
}
});
}
if (DEBUG) print(animation);
}
mHandlingOnAnimationUpdate = false;
} else {
if (DEBUG) print(animation);
}
}
/**
* Returns the current duration of property animations. If the duration was set on this object,
* that value is returned. Otherwise, the default value of the underlying Animator is returned.
*
* @see #setDuration(long)
* @return The duration of animations, in milliseconds.
*/
public long getDuration() {
if (mDurationSet) {
return mDuration;
} else {
// Just return the default from ValueAnimator, since that's what we'd get if
// the value has not been set otherwise
if (mTempValueAnimator == null) {
mTempValueAnimator = new ValueAnimator();
}
return mTempValueAnimator.getDuration();
}
}
public void print(ValueAnimator animation) {
float flatFraction = animation.getCurrentPlayTime() / (float) animation.getDuration();
Log.d(
"FirstFrameAnimatorHelper",
sGlobalFrameCounter
+ "("
+ (sGlobalFrameCounter - mStartFrame)
+ ") "
+ mTarget
+ " dirty? "
+ mTarget.isDirty()
+ " "
+ flatFraction
+ " "
+ this
+ " "
+ animation);
}