UITextField losing firstResponder after view appears
first-responder, objective-c, uipageviewcontroller
Solution
I don't really understand the nature of what was causing my issue, but I was able to fix it by wrapping the call in an async dispatch in `viewDidAppear`:
dispatch_async(dispatch_get_main_queue(), ^{
MapManualViewController *strongSelf = weakSelf;
[strongSelf.locationQuery becomeFirstResponder];
});
Problem
I have a `UIPageViewController`. One page has a single button, and the other page has a `UITextField` with a button. When the page scrolls to the view with the field, I'd like it to `becomeFirstResponder` and open the keyboard. Here's what happens: I call `[self.locationQuery becomeFirstResponder]` ViewController's `viewDidAppear` method. But it never opens the keyboard. I do the same in `viewWillAppear`, and it appears briefly, but then is quickly dismissed. If I'm on the page with the text field, and pull the page partway and let it go (without changing pages), `self.locationQuery` receives focus just fine. It seems like something else is grabbing firstResponder status from the field, but I haven't the faintest idea what, and why it would only be happening when the page changed (rather than revealed after a failed page turn). Any ideas? Update I created a way to crawl the views to see if any other views were, indeed, taking firstResponder (from an answer to this question: Get the current first responder without using a private API). Results: When I explicitly give first responder to the text field, the method reports it has first responder status. When I don't, it returns `null`. Now I'm even more confused.