控制 - 拖动以在Xcode 5中创建IBAction以关闭键盘？

Question

I have a view controller with a text field. I'm trying to create an IBAction to dismiss they keyboard when user taps outside the text field by control-dragging from outside the text field in the Xib file to my .h file, but I don't get the option to choose "Action," only "Outlet" and "Outlet collection." I don't even get a window that asks me to choose when I control drag inside a *.m file. What am I missing?

I was able to do this in Xcode 4.

Answer 1

When you ctrl-drag from "outside the text field", you are most likely interacting with the top-level view of the view controller. This is a UIView object which does not have actions. Only views that inherit from UIControl have actions, eg buttons, text fields. This is not an XCode 4 vs 5 issue -- it's always been this way.

In your view controller, override touchesBegan:withEvent: . Make a call to [self.view endEditing] to dismiss the keyboard.

This is possible because your view controller inherits from the UIResponder class, as do UIViews . When the user touches something on the screen, the event gets passed up the responder chain, eg from subview to parent view to parent view controller etc., until one of those responders decides to respond to or purposefully discard that event. By overriding touchesBegan:withEvent: , your view controller can handle that event and do something meaningful (like dismiss the keyboard).

Answer 2

A simple solution would be using a simple UITapGestureRecognizer added to the "main" view.

    UITapGestureRecognizer *gestureRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(hideKeyboard)];
    gestureRecognizer.cancelsTouchesInView = NO;
    [self.view addGestureRecognizer:gestureRecognizer];

Then the method hideKeyboard:

- (void)hideKeyboard
{
    [[UIApplication sharedApplication] sendAction:@selector(resignFirstResponder) to:nil from:nil forEvent:nil];
} <br>

The tap is sent through views until it finds one that could manage it, like the view controller view that triggers the gesture.

Answer 3

Use this code on your .m file

- (BOOL)textFieldShouldBeginEditing:(UITextField *)textField {

        selectedTextField = textField;
        return YES;
}

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
        [selectedTextField resignFirstResponder];
}