LinearAnimationInstance unable to run one-shot more than once

[BobaTrek]

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]

Hi @BobaTrek have you taken a look at OneShotAnimation?

[BobaTrek]

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]

I'll take a deeper look into this soon.

[HayesGordon]

Closing this as it's something we won't change in the short-medium term, and in the long term this underlying Dart code will be replaced with a C++ counterpart and the API will look different.