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Fix IllegalStateException in looped timing native animation

Summary:
This PR fixes regression introduced in #17896 with IllegalStateException being thrown in FrameBasedAnimationDriver.

After investigating it seemed that the root cause was the code responsible for looping animations that was setting next frame time by adding the frame interval to the current time. In some circumstances the next frame would run earlier than that and as a result the calculated frame index was negative.

Here is the stacktrace as reported by axemclion https://github.com/facebook/react-native/pull/17896/files#r170007224
```
Caused by: java.lang.IllegalStateException: Calculated frame index should never be lower than 0
	at com.facebook.react.animated.FrameBasedAnimationDriver.runAnimationStep(FrameBasedAnimationDriver.java:60)
	at com.facebook.react.animated.NativeAnimatedNodesManager.runUpdates(NativeAnimatedNodesManager.java:444)
	at com.facebook.react.animated.NativeAnimatedModule$1.doFrameGuarded(NativeAnimatedModule.java:100)
	at com.facebook.react.uimanager.GuardedFrameCallback.doFrame(GuardedFrameCallback.java:29)
```

Run native animated tests suite. Run RNTester and scroll to the loop animation and see it working correctly

[ANDROID][BUGFIX][Animated] - Fix exception thrown by timing animation when looping
Closes #18061

Differential Revision: D7059335

Pulled By: hramos

fbshipit-source-id: b08dfd1398d028eeeabeb11863743666379da374
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kmagiera authored and facebook-github-bot committed Feb 22, 2018
1 parent cf0193f commit ef9d1fba237c08a158c8f32e823f229921e7c052
@@ -52,7 +52,10 @@ public void resetConfig(ReadableMap config) {
public void runAnimationStep(long frameTimeNanos) {
if (mStartFrameTimeNanos < 0) {
mStartFrameTimeNanos = frameTimeNanos;
mFromValue = mAnimatedValue.mValue;
if (mCurrentLoop == 1) {
// initiate start value when animation runs for the first time
mFromValue = mAnimatedValue.mValue;
}
}
long timeFromStartMillis = (frameTimeNanos - mStartFrameTimeNanos) / 1000000;
int frameIndex = (int) Math.round(timeFromStartMillis / FRAME_TIME_MILLIS);
@@ -66,7 +69,7 @@ public void runAnimationStep(long frameTimeNanos) {
if (frameIndex >= mFrames.length - 1) {
nextValue = mToValue;
if (mIterations == -1 || mCurrentLoop < mIterations) { // looping animation, return to start
mStartFrameTimeNanos = frameTimeNanos + ((long) FRAME_TIME_MILLIS) * 1000000L;
mStartFrameTimeNanos = -1;
mCurrentLoop++;
} else { // animation has completed, no more frames left
mHasFinished = true;

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