How I tell my UITextField (code) to resign first responder? - xcode

Question

I have created my UITextField by code, without InterfaceBuilder. I want the keyboard to disappear when the button "Done" is pushed. How does the code know that I am referending to an UITextField and no to other one
First, thanks a lot.
My code is like this:
-(void)viewDidLoad {
[super viewDidLoad];
field = [[UITextField alloc] initWithFrame:CGRectMake(30, 100, 185, 30)];
field.adjustsFontSizeToFitWidth = YES;
field.textColor = [UIColor blackColor];
field.placeholder = #"Text";
field.keyboardType = UIKeyboardTypeDefault;
field.returnKeyType = UIReturnKeyDone;
field.backgroundColor = [UIColor blueColor];
field.delegate = self;
[self.view addSubview:field];
}
......
-(BOOL)textFieldShouldReturn:(UITextField *)textField
{
[textField resignFirstResponder];
}
With this code I push the button Done and nothing happen. Is like that how you say?
Edit:
I've created two UITextField how I did with the previous one. But now, for each row I do this:
if ([indexPath row] == 0) {
[cell.contentView addSubview:pTextField];
}
else {
[cell.contentView addSubview:pTextField];
}
So with this code, the program received signal "EXC_BAD_ACCESS". Any idea why happen this?

Answer 1

How does the code know that I am referending to an UITextField and no to other one
Your textFieldShouldReturn: method's textField parameter will always be the text field that is currently active.
The method has to return a BOOL, you should be getting compiler warnings with it as it stands. Try
-(BOOL)textFieldShouldReturn:(UITextField *)textField
{
[textField resignFirstResponder];
return YES;
}
Note that you are also currently leaking memory in the way you add the text field. You should set it as a property as per WrightCS's answer so that you can refer to it later on. So at the end of your viewDidLoad:
self.myTextField = field;
[field release];

Answer 2

Define your textField in your header, then you can use the following:
.h
#interface MyeViewController : UIViewController <UITextFieldDelegate>
{
UITextField * myTextField;
}
#end
.m
-(BOOL)textFieldShouldReturn:(UITextField *)textField
{
[myTextField resignFirstResponder];
/* textField here is referenced from
textFieldShouldReturn:(UITextField *)textField
*/
}

Answer 3

Make sure you set the delegate of your programatically created UITextField to self (the view controller that created the object) and implement the appropriate UITextFieldDelegate method (I think its textFieldShouldReturn:) and call in that method resignFirstResponder on the textField argument passed to the delegate method (which will be your UITextField).