I have a kinda complex vector drawable that I want to animate. I used @RomanNurik's web tool to create the animation from a svg
That gives me a valid <animated-vector> according to the documentatios. It's an "all in one" XML file.
The xml has the drawable divided in 2 groups, each group containing 2 paths and has also added 4 animations, just as follows:
<animated-vector xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:aapt="http://schemas.android.com/aapt">
<aapt:attr name="android:drawable">
<vector xmlns:android="http://schemas.android.com/apk/res/android"
android:width="56dp"
android:height="56dp"
android:viewportHeight="56.0"
android:viewportWidth="56.0">
<group
android:name="group_1"
android:pivotX="25"
android:pivotY="25">
<path
android:name="path_3_1"
... />
<path
android:name="path"
... />
</group>
<group
android:name="group"
android:pivotX="25"
android:pivotY="25">
<path
android:name="path_1"
... />
<path
android:name="path_2"
... />
</group>
</vector>
</aapt:attr>
<target android:name="path">
<aapt:attr name="android:animation">
<set xmlns:android="http://schemas.android.com/apk/res/android">
<objectAnimator
android:name="path"
... />
<objectAnimator
android:name="path"
.../>
</set>
</aapt:attr>
</target>
<target android:name="group_1">
<aapt:attr name="android:animation">
<set xmlns:android="http://schemas.android.com/apk/res/android">
<objectAnimator
android:name="group_1"
... />
<objectAnimator
android:name="group_1"
... />
<objectAnimator
android:name="group_1"
... />
<objectAnimator
android:name="group_1"
... />
</set>
</aapt:attr>
</target>
<target android:name="group">
<aapt:attr name="android:animation">
<set xmlns:android="http://schemas.android.com/apk/res/android">
<objectAnimator
android:name="group"
... />
<objectAnimator
android:name="group"
... />
<objectAnimator
android:name="group"
... />
<objectAnimator
android:name="group"
... />
</set>
</aapt:attr>
</target>
<target android:name="path_3_1">
<aapt:attr name="android:animation">
<set xmlns:android="http://schemas.android.com/apk/res/android">
<objectAnimator
android:name="path_3_1"
... />
<objectAnimator
android:name="path_3_1"
... />
</set>
</aapt:attr>
</target>
</animated-vector>
Issue number 1:
I cannot use android:repeatCount="infinite" since the ObjectAnimators have different android:duration and android:startOffset values, that would mess up the animation after some runs. So the way to go is repeat it programmatically. Fair enough.
Issue number 2:
Neither AnimatedVectorDrawableCompat or AnimatedVectorDrawable have a method that says animation should loop.
Issue number 3:
AnimatedVectorDrawableCompat does not have a registerAnimationCallback() so I can listen to onAnimationEnd and restart the animation myself. At this point, I gave up on retrocompatibility.
Issue number 4:
The current implementation I have that uses registerAnimationCallback() from AnimatedVectorDrawable only works at android API 25, even though the methods were added in API 23
AnimatedVectorDrawable drawable = (AnimatedVectorDrawable) context().getDrawable(R.drawable.long_press_anim);
imageView.setImageDrawable(drawable);
drawable.registerAnimationCallback(new Animatable2.AnimationCallback() {
@Override
public void onAnimationEnd(Drawable drawable) {
super.onAnimationEnd(drawable);
((AnimatedVectorDrawable) drawable).start();
}
});
drawable.start();
In API 23 and 24 the animation runs as a one-shot, it does not repeat.
Any ideas how to solve this? I;m about to give up and use a shit png sequence instead.
The official and working answer is here: https://issuetracker.google.com/issues/64591234
This code works with >= API 16 (probably also 14-15). I'm using support library 26.1.0 and vectorDrawables.useSupportLibrary = true (so I can refer to a vector drawable in xml without crashing)
animatedVector = AnimatedVectorDrawableCompat.create(getContext(), R.drawable.animated_clock);
ringingAlarmImage.setImageDrawable(animatedVector);
final Handler mainHandler = new Handler(Looper.getMainLooper());
animatedVector.registerAnimationCallback(new Animatable2Compat.AnimationCallback() {
@Override
public void onAnimationEnd(final Drawable drawable) {
mainHandler.post(new Runnable() {
@Override
public void run() {
animatedVector.start();
}
});
}
});
animatedVector.start();
I have the same issue so I did this:
// setup and set animation
AnimatedVectorDrawableCompat animatedVector = AnimatedVectorDrawableCompat.create(context, R.drawable.listening_vector_anim);
imageView.setImageDrawable(animatedVector);
// loop animation!
new Thread(() -> {
while (imageView.isAttachedToWindow()) {
try {
imageView.post(() -> animatedVector.start());
Thread.sleep(2000); //depends on your animation duration
} catch (Exception e) {
e.printStackTrace();
}
}
}).start();
This thread will die when the ImageView detach from window.
I am giving a few tips
Issue Number 1: android:repeatCount="0" to make it infinite. and android:repeatMode="restart" or "reverse".
Issue Number 2: Looping is there in ObjectAnimator. The above, under Number one is the same.
Issue Number 3:Listener is there on ObjectAnimator. If you add a listener you can watch onAnimationEnd or onAnimationStart.
Instead of a single file if you opt for the other alternative of 3 files as given in documentation for AnimatedVectorDrawable you can feel comfortable to handle.
The three are 1. VectorDrawable, 2. AnimatedVectorDrawable and 3.ObjectAnimator
The AnimatedVectorDrawable links the other two.
There is a good article in Ray Wenderlich's site with a rocket and a doge animation at : https://www.raywenderlich.com/173345/android-animation-tutorial-with-kotlin (with java code).
You may also read the article "Introduction to Icon animation Techniques" by Mr.Alex Lockwood at : https://www.androiddesignpatterns.com/2016/11/introduction-to-icon-animation-techniques.html The source code is also available in GitHub.
来源：https://stackoverflow.com/questions/41767676/how-to-restart-android-animatedvectordrawables-animations