How to handle animation completion?

[zulkarnain-shah]

I don't see any completion handlers that we can use when the animation completes. How to achieve that? Is there a method I'm missing ?

[Eclair]

Hi @zulkarnain-shah,

There is no such callback. If you look closely to standard iOS ProgressView: https://developer.apple.com/documentation/uikit/uiprogressview, it doesn't have it either.
The idea is to have this control only to present things, and because you are in full control of what it is presenting - you can wait for time it ends animation and then execute your specific instructions.

Thanks,

[zulkarnain-shah]

I actually found a solution to that. In the callback handler of the method circleProgressBar.setHintTextGenerationBlock, I check when the progress == 1.0 then i do stuff that I need to do. A progress value of 1.0 means that animation has completed! Voila !

[Eclair]

Hehe, Well, if that's what you prefer ^_^
Usually I would separate presentation logic from business logic, because this is just a visual control, and it should not block other application logic.

[zulkarnain-shah]

It does the job for me. And its the correct calculation of the progress as well, isn't it ?

[Eclair]

@zulkarnain-shah
Yeah, that's true.
Don't get me wrong, it's just the source of this data. For example in this case, this updates comes like this:

progress set outside -> internal timer -> animation -> callback

And if timer or animation step in this chain would change - you can get wrong results in the callback. So instead of relying on last part of this chain, you can define everything outside (in your controller).

for example:

[_progressBar setProgress:0.5f animated:YES duration:0.5f];
// you timer that will fire after 0.5f (when animation should complete already)
// but it will be more reliable that UI element that just used to display things

To follow Single Responsibility Principle.