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rive-app / rive-flutter

Flutter runtime for Rive
https://rive.app
MIT License
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LinearAnimationInstance unable to run one-shot more than once #316

Open BobaTrek opened 1 year ago

BobaTrek commented 1 year ago

Description

The class LinearAnimationInstance sets _didLoop to true after completing a one-shot animation. The class LinearAnimationInstance then returns false for keepGoing because of the following line of code: bool get keepGoing => animation.loop != Loop.oneShot || !_didLoop;

Consequently, after running the animation once, setting controller.isActive back to true does not re-run the animation. Perhaps this is intentional?

Workaround?

I found the following code will allow you to re-run the animation (scPulse is my SpeedController which uses LinearAnimationInstance:

scPulse.instance.reset(); scPulse.instance.advance(0); // This sets _didloop back to false as a side effect; scPulse.isActive = true;

Should _didloop be set to false as part of the reset() call (or when isActive gets set false) instead of relying on the side effect of calling advance(0)?

HayesGordon commented 1 year ago

Hi @BobaTrek have you taken a look at OneShotAnimation?

BobaTrek commented 1 year ago

Yes, I did use OneShotAnimation first, but I need to be able to change the speed of the animation as well, so I switched to the SpeedController mechanism. I am still thinking _didloop should be set to false in the LinearAnimationInstance.reset() function, but at least for now there is a workaround by calling .advance(0).

(Switching to SpeedController has presented a different problem, see #317)

HayesGordon commented 1 year ago

I'll take a deeper look into this soon.