Correct (App Store Safe) way to resign a first responder?

Question

Hi,

What's the correct way to resign the current firstResponder?

I've seen the following: Looping through fields and calling resignFirstResponder on each.

[[self textFieldForRow:0] resignFirstResponder];
[[self textFieldForRow:1] resignFirstResponder];
[[self textFieldForRow:2] resignFirstResponder];
[[self textFieldForRow:3] resignFirstResponder];

And this which looks like it's calling a private function, is this app store safe?:

UIWindow *keyWindow = [[UIApplication sharedApplication] keyWindow];
UIView   *firstResponder = [keyWindow performSelector:@selector(firstResponder)];   
[firstResponder resignFirstResponder];      

Is there a better way?

Thanks!

Comments: Looks like the second method is using a private api and someone's app has been rejected because of it: link

Answer 1

The code you have up there is not calling any private function. What is happening is:

 //Gets the application window
 UIWindow *keyWindow = [[UIApplication sharedApplication] keyWindow];
 //Gets the first Responder View for the window
UIView   *firstResponder = [keyWindow performSelector:@selector(firstResponder)];  
//Make the UView resign the first responder 
[firstResponder resignFirstResponder];     

All of those are public functions, so you will not have any problem with the app store as far as I know.

Additionally is there a better way to do what exactly?. If you are talking about getting the UIView that is the firstResponder to the keyWindow, you could do when creating your uiview:

myView.tag = 100;

and to get it:

UIView *firstResponder = [self viewWithTag:100];

Answer 2

My suggestion would be to implement a hacky & slow version of firstResponder yourself in a category and then file a radar requesting they add the method. Something along these lines:

- (id)my_FirstResponder
    for view in [self subviews]
        if [self isFirstResponder]
            return self
        return [self my_firstResponder]
    return nil

Using performSelector: to invoke a method not in the public headers is definitely grounds for rejection, so don't do that. Oh, and don't forget to use a prefix (like the above code does) when adding a category to avoid conflicts.

Answer 3

Have a look at this question: How do I [legally] get the current first responder on the screen on an iPhone?

My answer to that question should work perfectly in your situation.

Answer 4

There's actually an API to do this:

[view endEditing:YES];

http://developer.apple.com/iphone/library/documentation/UIKit/Reference/UIView_Class/UIView/UIView.html#//apple_ref/occ/instm/UIView/endEditing: