UITextField and keyboard controls checking if field has data - ios

Question

I am using BSKeyboard Controls to have a next/previous and done button above the keyboard on login fields for username and password.
What I want to achieve is:
- When one of the fields is blank the done button should say 'Done'
- When both fields have at least one character it should say 'Login'
I understand there are multiple ways to check a textfield contents, hasText isEqualToString !=nil etc. But I am trying to check characters here I guess.
I need to know what would be the best location to put an if statement and which to use.
My fields are
self.usernameField
self.passwordField
My Keyboard control is updated like this:
self.keyboardControls.doneTitle = NSLocalizedString(#"KeyboardControlsDone", #"test");
OR
self.keyboardControls.doneTitle = NSLocalizedString(#"KeyboardControlsLogin", #"test");
Updated Method:
NSString *newText = [textField.text stringByReplacingCharactersInRange:range withString:string];
UITextField *otherTextField;
if (textField == self.passwordField)
{
otherTextField = self.usernameField;
}
else
{
otherTextField = self.passwordField;
}
if ([newText length] > 0 && [otherTextField.text length] > 0)
{
self.keyboardControls.doneTitle = NSLocalizedString(#"KeyboardControlsLogin",#"Button for Keyboard Controls on Login page");
} else {
self.keyboardControls.doneTitle = NSLocalizedString(#"KeyboardControlsDone", #"test");
}

Answer 1

You can implement textField:shouldChangeCharactersInRange:replacementString: of UITextFieldDelegate to execute whatever you want when the user enters a key.
Something like this:
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
NSString *newText = [textField.text stringByReplacingCharactersInRange:range withString:string];
UITextField *otherTextField;
if (textField == self.passwordField)
{
otherTextField = self.usernameField;
}
else
{
otherTextField = self.passwordField;
}
if ([newText length] > 0 && [otherTextField.text length] > 0)
{
// Your code
}
return YES;
}
EDIT
Instead of using that delegate method,use the event editing changed. You have to set the action for that event with IB or by code, and it would look like this:
- (IBAction) textFieldEditingChanged
{
if ([self.usernameField.text length] > 0 && [self.passwordField.text length] > 0)
{
self.keyboardControls.doneTitle = NSLocalizedString(#"KeyboardControlsLogin",#"Button for Keyboard Controls on Login page");
} else {
self.keyboardControls.doneTitle = NSLocalizedString(#"KeyboardControlsDone", #"test");
}
}