[FEATURE] Support external registration and cancellation of animations

[josxha]

What do you want implemented?

While writing the flutter_map_compass plugin, I stumbled upon some problems.
It is currently not possible to interact with ongoing map animations or interact with animations of other plugins.

#1715 (comment) describes the scope of animations as:

It's for plugins to provide animations for programmatic controls.

Because we don't see programmatic control of animations as a part of the core package it has a couple of limitations for plugins. Plugins are not able to interact with ongoing animations of other plugins or to cancel animations caused by gestures.

What other alternatives are available?

I tried use flutter_map_animations for the animations as this is probably the prefered animation system but I wasn't able to without a much more complicated setup for users.
Required steps for other plugins to use fma:

• Let the user implement flutter_map_animations
• Get the animation map controller as a parameter

Furthermore flutter_map_animations can't detect animations caused by gestures either, so it wouldn't really solve the problem.

Can you provide any other information?

In this video I perform a fling gesture and trigger a plugin gesture using flutter_map_compass. Both gestures play while the first should get cancelled for a better user experience.

animation.not.cancelled.2.1.mp4

Severity

Obtrusive: No workarounds are available, and this is essential to me