In my code there is a rare instance where the observer will be removed a second time. Will this cause issues?
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In my code there is a rare instance where the observer will be removed a second time. Will this cause issues?
Yes. If you’re not an observer and you try to remove yourself, your app will crash. There is no way to check if you’re registered, so you’ll have to create an ivar that flags whether you’re added as an observer (or, perhaps even better, counts how many times you’re added as an observer) and check the ivar before actually removing yourself.
EDIT: Turns out you can remove yourself before you’re added, so I guess, although it’s not a great design, it wouldn’t matter much if you removed yourself twice.