Add delegate methods to notify that CropView became resettable

[xinatanil]

I'm building an embedded version of the CropViewController with my own overlay UI. To my surprise, there was no easy way for me to activate/deactivate "reset" button. While CropViewDelegate provides the necessary methods, accessing it is impossible (or I didn't figure it out). The most simple solution, like subclassing CropViewController and overriding "didBecomeResettable" is impossible because "extension CropViewController: CropViewDelegate" is not public.

The only solution I see right now is to fork the repo and manually add necessary methods to CropViewControllerDelegate. Is there a simpler and more elegant way?

[guoyingtao]

@xinatanil Do you mean you want to provide two status active/deactivate for reset button? The current logic is to hide/show reset button when checking if it is resettable.

[xinatanil]

Yes, something like that via KVO or delegate method. For my custom UI I'd like to hide the reset button when it's not needed.

[guoyingtao]

@xinatanil So do you mean you want to set your own icon for reset button?

[xinatanil]

No, I want a way for me to know that reset button has been activated/deactivated, so that I could disable my own custom UI elements. Currently, I see no easy way for that.

[guoyingtao]

@xinatanil For activated status, you can use delegate function cropViewControllerDidImageTransformed. For deactivated status, I can add a new delegate function for it.

[xinatanil]

That'd be great! Something like func cropViewController(_ cropViewController: CropViewController, didBecomeResettable resettable: Bool) would be amazing

[guoyingtao]

@xinatanil Please check #317 to see if it works for you, then I can make a new release later.

[xinatanil]

Looks fantastic! Thank you for a quick response!

[guoyingtao]

@xinatanil Just released Mantis 2.12.0 for this feature. Please have a try.