如果嵌入到UINavigationController中，则在调用成为firstResponder并设置文本时，UITextField中缺少文本

Question

I created a simple project as a test case for this issue.

I have one simple view, with just one UITextField, embedded inside UINavigationController.

If I call:

self.textField.text = @"TEST";
[self.textField becomeFirstResponder];

inside viewDidLoad. Text field appears, but text is garbled, not visible or out of alignment.

If I either set text or call becomeFirstResponder in viewDidAppear this issue does not occur, but I don't get desired results as keyboard animation is delayed, and I need keyboard and text to be visible while new view shows up.

Test Case: Test Project

Answer 1

You can only call it on that view if it is part of a view hierarchy. If the view's window property holds a UIWindow object. Try like this .

-(void)viewWillAppear:(BOOL)animated
{

    self.textField.text = @"TEST";
    [super viewWillAppear:animated];
    dispatch_async(dispatch_get_main_queue(), ^{
        [self.textField becomeFirstResponder];
    });
}