Develop Reference

How to create Accelerate - Linear - Decelerate animation effect in android using ValueAnimator?

Now I have to create an animation of a spinning fan. When user click POWER ON button, this fan begin to spin, then keep it's spinning speed at some level.When user click POWER OFF button, it slowing down then it stop.
I make some code as follows：
ImageView mFanImageview;
private ValueAnimator mFanValueAnimator;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_centripetal_particle);
ButterKnife.bind(this);
}
private void startFan() {
mFanValueAnimator = new ValueAnimator();
mFanValueAnimator.setDuration(1000);
mFanValueAnimator.setFloatValues(mFanImageview.getRotation(), mFanImageview.getRotation() + 360);
mFanValueAnimator.setInterpolator(new AccelerateInterpolator());
mFanValueAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
#Override
public void onAnimationUpdate(ValueAnimator animation) {
mFanImageview.setRotation((Float) animation.getAnimatedValue());
}
});
mFanValueAnimator.addListener(new AnimatorListenerAdapter() {
#Override
public void onAnimationEnd(Animator animation) {
mFanValueAnimator = new ValueAnimator();
mFanValueAnimator.setDuration(500);
mFanValueAnimator.setFloatValues(mFanImageview.getRotation(), mFanImageview.getRotation() + 360);
mFanValueAnimator.setRepeatCount(ValueAnimator.INFINITE);
mFanValueAnimator.setRepeatMode(ValueAnimator.RESTART);
mFanValueAnimator.setInterpolator(new LinearInterpolator());
mFanValueAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
#Override
public void onAnimationUpdate(ValueAnimator animation) {
mFanImageview.setRotation((Float) animation.getAnimatedValue());
}
});
mFanValueAnimator.addListener(new AnimatorListenerAdapter() {
#Override
public void onAnimationCancel(Animator animation) {
stopFanValueAnimator().start();
}
});
mFanValueAnimator.start();
}
#Override
public void onAnimationCancel(Animator animation) {
stopFanValueAnimator().start();
}
});
mFanValueAnimator.start();
}
private ValueAnimator stopFanValueAnimator() {
ValueAnimator stopAnimator = new ValueAnimator();
stopAnimator.setDuration(1000);
stopAnimator.setFloatValues(mFanImageview.getRotation(), mFanImageview.getRotation() + 360);
stopAnimator.setInterpolator(new DecelerateInterpolator());
stopAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
#Override
public void onAnimationUpdate(ValueAnimator animation) {
mFanImageview.setRotation((Float) animation.getAnimatedValue());
}
});
return stopAnimator;
}
#OnClick(R.id.stop_button)
public void onStopButtonClicked() {
mFanValueAnimator.cancel();
}
#OnClick(R.id.start_button)
public void onStartButtonClicked() {
startFan();
}
The animation above seems ok, but I found that the fan spinning speed at the end of AccelerateInterpolator animator is hard to match the beginning of LinearInterpolator.I have to adjust duration of LinearInterpolator animator carefully.
How can I get the update rate at the end of AccelerateInterpolator animator then set the right duration of LinearInterpolator animator?

I think the best approach is set accelerate interpolator initially, and on repeat again set LinearInterpolator. Now in case of repeat put a flag for handling switch off. If the switch off demanded then change value of switch Off flag that will apply Decelerate interpolator and make sure that the animation will not run again.
mFanValueAnimator.addListener(new AnimatorListenerAdapter() {
#Override
public void onAnimationRepeat(Animator animation) {
if (switchOff) {
animation.setInterpolator(new DecelerateInterpolator());
} else {
animation.setInterpolator(new LinearInterpolator());
}
}
});

how do i know ObjectAnimator has runned?

I put three ObjectAnimator into AnimatorSet ,when I cancel AnimatorSet or AnimatorSet finishes ,i need record the getAnimatedValue . But when I cancel the AnimatorSet, a ObjectAnimator maybe not had runned and i can call isRunning in onAnimationCancel but how do I judge this ObjectAnimator had runned at onAnimationEnd .
animatorSet.addListener(new Animator.AnimatorListener() {
#Override
public void onAnimationStart(Animator animation) {
}
#Override
public void onAnimationEnd(Animator animation) {
mSunMovPos = (float) sunAnimator.getAnimatedValue();
mCurSunSetColor = (int) sunSetAnimator.getAnimatedValue();
//How do judge nightAnimator had runned ?
mCurNightColor = (int) nightAnimator.getAnimatedValue();
}
#Override
public void onAnimationCancel(Animator animation) {
mSunMovPos = (float) sunAnimator.getAnimatedValue();
mCurSunSetColor = (int) sunSetAnimator.getAnimatedValue();
if (nightAnimator.isRunning())
mCurNightColor = (int) nightAnimator.getAnimatedValue();
}
#Override
public void onAnimationRepeat(Animator animation) {
}
});

How to reset ObjectAnimator to it's initial status?

I want to vibrate a view with scaleX and scaleY, and I am doing it with this code, but the problem is that sometimes the view is not correctly reset, and it shows with the scale applied...
I want that when the animation ends, the view must be seen with its original status always
this is the code:
ObjectAnimator scaleX = ObjectAnimator.ofFloat(view, "scaleX", 1f, 0.9f);
scaleX.setDuration(50);
scaleX.setRepeatCount(5);
scaleX.setRepeatMode(Animation.REVERSE);
ObjectAnimator scaleY = ObjectAnimator.ofFloat(view, "scaleY", 1f, 0.9f);
scaleY.setDuration(50);
scaleY.setRepeatCount(5);
scaleY.setRepeatMode(Animation.REVERSE);
set.play(scaleX).with(scaleY);
set.start();
Thanks

For ValueAnimator and ObjectAnimator can be like this a try:
animator.addListener(new AnimatorListenerAdapter() {
#Override
public void onAnimationEnd(Animator animation) {
animation.removeListener(this);
animation.setDuration(0);
((ValueAnimator) animation).reverse();
}
});
UPDATE
On Android 7 it doesn't work.
Best way use the interpolator.
public class ReverseInterpolator implements Interpolator {
private final Interpolator delegate;
public ReverseInterpolator(Interpolator delegate){
this.delegate = delegate;
}
public ReverseInterpolator(){
this(new LinearInterpolator());
}
#Override
public float getInterpolation(float input) {
return 1 - delegate.getInterpolation(input);
}
}
In your code
animator.addListener(new AnimatorListenerAdapter() {
#Override
public void onAnimationEnd(Animator animation) {
animation.removeListener(this);
animation.setDuration(0);
animation.setInterpolator(new ReverseInterpolator());
animation.start();
}
});

According to the docs(Property Animation):
The property animation system can animate Views on the screen by changing the actual properties in the View objects. In addition, Views also automatically call the invalidate() method to refresh the screen whenever its properties are changed.
so you can use AnimatorListener to listen the animation event, then just reset the view property you animate. let's say cancel event and scaleX property:
scaleAnimator.setListener(new AnimatorListenerAdapter() {
#Override
public void onAnimationCancel(Animator animation) {
scaleView.setScaleX(0)
}
});
Hope this can help a bit.

You can add an AnimatorListener, to be notified when the animation ends:
scaleY.addListener(new AnimatorListener() {
#Override
public void onAnimationEnd(Animator animation) {
// TODO Restore view
}
#Override
public void onAnimationStart(Animator animation) {
}
#Override
public void onAnimationRepeat(Animator animation) {
}
#Override
public void onAnimationCancel(Animator animation) {
}
});

Api 21 Circular Reveal Animation not working

I can't get the circular reveal animation to work.
I think I checked the most obvious things:
It starts, width and height are > 0 and it is visible, no Exception..
I load some data from the internet and display it in the view(fab)
The animation should only play after the download finishes.
TmdbHelper helper = new TmdbHelper();
helper.getMovieById(id, "en", new TmdbHelper.ResultListener() {
#Override
public void onResultReceived(JSONObject result) {
// called when finished downloading
try {
String rating = result.getString("vote_average");
AnimationHelper.circularReveal(fab, 500, 0);
fab.setText(rating);
} catch (JSONException e) {
e.printStackTrace();
}
}
});
AnimationHelper:
public static void circularReveal(final View view, final long duration, long startDelay) {
// get the center for the clipping circle
int cx = (view.getLeft() + view.getRight()) / 2;
int cy = (view.getTop() + view.getBottom()) / 2;
// get the final radius for the clipping circle
int finalRadius = Math.max(view.getWidth(), view.getHeight());
// create the animator for this view (the start radius is zero)
Animator anim =
ViewAnimationUtils.createCircularReveal(view, cx, cy, 0, finalRadius);
anim.setDuration(duration);
anim.setStartDelay(startDelay);
anim.addListener(new Animator.AnimatorListener() {
#Override
public void onAnimationStart(Animator animation) {
view.setVisibility(View.VISIBLE);
}
#Override
public void onAnimationEnd(Animator animation) {
}
#Override
public void onAnimationCancel(Animator animation) {
}
#Override
public void onAnimationRepeat(Animator animation) {}
});
// make the view visible and start the animation
anim.start();
}
I use the circular reveal animation in other parts like this to make sure the view is attached, and it works:
headerContainer.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
#Override
public void onGlobalLayout() {
headerContainer.getViewTreeObserver().removeOnGlobalLayoutListener(this);
AnimationHelper.circularReveal(headerContainer, 500, 200);
}
});

Perhaps you should erase this line inside your onResultRecieved():
fab.setVisibility(View.VISIBLE);
My assumption is that your circular reveal method is working just fine. It is because of you have made the FAB visible before the animation even begin, you can't see it in action.
As an addition, those lines you've shown which is working doesn't have fab.setVisibility(View.VISIBLE) called anywhere in it.

1st Approach:
Try Transition Listener.
getWindow().getSharedElementExitTransition().addListener(new Transition.TransitionListener() {
#Override
public void onTransitionStart(Transition transition) {
}
#Override
public void onTransitionEnd(Transition transition) {
}
#Override
public void onTransitionCancel(Transition transition) {
}
#Override
public void onTransitionPause(Transition transition) {
}
#Override
public void onTransitionResume(Transition transition) {
}
});
2nd Approach: Try setting start delay and listener to the reveal animation and when animation starts then set the view visible
if (Build.VERSION.SDK_INT >= 21) {
Animator anim = ViewAnimationUtils.createCircularReveal(viewRoot, cx, cy, 0, finalRadius);
anim.setStartDelay(300);
anim.setDuration(1000);
anim.setInterpolator(new DecelerateInterpolator());
anim.addListener(new Animator.AnimatorListener() {
#Override
public void onAnimationStart(Animator animation) {
viewRoot.setVisibility(View.VISIBLE);
}
#Override
public void onAnimationEnd(Animator animation) {
}
#Override
public void onAnimationCancel(Animator animation) {
}
#Override
public void onAnimationRepeat(Animator animation) {
}
});
anim.start();
}
}
#Override
public void onAnimationCancel(Animator animation) {
}
#Override
public void onAnimationRepeat(Animator animation) {
}
});
anim.start();

Check if AnimatorSet has finished animation?

I'm trying to animate buttons with fade in animation using AnimatorSet
Button fades in > Click button > Remaining buttons fade out
So in order to do this, I want to set the onClickListner after the animation is completed, but that doesn't seem to work. Clicking a button in the middle of the animation triggers the onClick action:
setQuestion = new AnimatorSet();
setQuestion.playSequentially(fadeinAnimationQ,fadeinAnimation1,fadeinAnimation2,fadeinAnimation3,fadeinAnimation4,fadeinAnimation5);
setQuestion.start();
This is the method that checks if the animation has finished.
private void checkAnimation() {
while (true) {
// Check if animation has ended
if (setQuestion.isRunning() == false) {
assignListners();
break;
}
}
}

You can set an AnimatorListener on fadeinAnimation5.
This will give you an onAnimationEnd callback.
fadeinAnimation5.addListener(new AnimatorListener() {
#Override
public void onAnimationStart(Animator animation) {
// ...
}
#Override
public void onAnimationRepeat(Animator animation) {
// ...
}
#Override
public void onAnimationEnd(Animator animation) {
// ...
}
#Override
public void onAnimationCancel(Animator animation) {
// ...
}
});
Or, as suggested by slott use an AnimatorListenerAdapter
fadeinAnimation5.addListener(new AnimatorListenerAdapter() {
#Override
public void onAnimationEnd(Animator animation) {
// ...
}
}

I was having a similar problem and here is how I solved it:
private void crossFadeAnimation(final View fadeInTarget, final View fadeOutTarget, long duration){
AnimatorSet mAnimationSet = new AnimatorSet();
ObjectAnimator fadeOut = ObjectAnimator.ofFloat(fadeOutTarget, View.ALPHA, 1f, 0f);
fadeOut.addListener(new Animator.AnimatorListener() {
#Override
public void onAnimationStart(Animator animation) {
}
#Override
public void onAnimationEnd(Animator animation) {
fadeOutTarget.setVisibility(View.GONE);
}
#Override
public void onAnimationCancel(Animator animation) {
}
#Override
public void onAnimationRepeat(Animator animation) {
}
});
fadeOut.setInterpolator(new LinearInterpolator());
ObjectAnimator fadeIn = ObjectAnimator.ofFloat(fadeInTarget, View.ALPHA, 0f, 1f);
fadeIn.addListener(new Animator.AnimatorListener() {
#Override
public void onAnimationStart(Animator animation) {
fadeInTarget.setVisibility(View.VISIBLE);
}
#Override
public void onAnimationEnd(Animator animation) {}
#Override
public void onAnimationCancel(Animator animation) {}
#Override
public void onAnimationRepeat(Animator animation) {}
});
fadeIn.setInterpolator(new LinearInterpolator());
mAnimationSet.setDuration(duration);
mAnimationSet.playTogether(fadeOut, fadeIn);
mAnimationSet.start();
}

You can actually set a listener to the AnimatorSet directly since AnimatorSet inherits from Animator. Here's some code:
import android.animation.Animator;
AnimatorSet setQuestion = new AnimatorSet();
setQuestion.playSequentially(fadeinAnimationQ,fadeinAnimation1,fadeinAnimation2,fadeinAnimation3,fadeinAnimation4,fadeinAnimation5);
setQuestion.addListener(new Animator.AnimatorListener() {
#Override
public void onAnimationStart(Animator animator) {
}
#Override
public void onAnimationEnd(Animator animator) {
// !! turn on your onClickListener here !!
}
#Override
public void onAnimationCancel(Animator animator) {
}
#Override
public void onAnimationRepeat(Animator animator) {
}
});
setQuestion.start();