Question

Is there a way to only allow the user enter one word in the UITextField? If so, how?

Here’s the current code that I’m using:

-(BOOL) textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string{

_disallowedCharacters = [NSCharacterSet whitespaceCharacterSet];

for(int i = 0; i < [_searchBox.text length]; i++){
    unichar c = [_searchBox.text characterAtIndex:i];
    if (![_disallowedCharacters characterIsMember:c])
    {
        return NO;
    }
}
return YES;
}

Answer 1

Use the UITextFieldDelegate protocol:

- (BOOL) textField:(UITextField*)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString*)textEntered
{
    for (int i = 0; i < [textEntered length]; i++)
    {
        unichar c = [textEntered characterAtIndex:i];
        if ([disallowedCharacters characterIsMember:c])
        {
            return NO;
        }
    }
    return YES;
}

where disallowedCharacters is an NSCharacterSet containing the characters that should not be accepted by the keyboard, i.e. a space, punctuation, numbers, etc:

self.disallowedCharacters = [NSCharacterSet characterSetWithCharactersInString:@" ,.123"];