iPhone Developer's Cookbook: ModalAlert Frozen

Question

I've used a recipe from the iPhone Developer's Cookbook called ModalAlert in order to get some text from a user; however, when the alert is shown, the keyboard and buttons are frozen. Here is the code for the modal alert.

+(NSString *) textQueryWith: (NSString *)question prompt: (NSString *)prompt button1: (NSString *)button1 button2:(NSString *) button2
{
    // Create alert
    CFRunLoopRef currentLoop = CFRunLoopGetCurrent();
    ModalAlertDelegate *madelegate = [[ModalAlertDelegate alloc] initWithRunLoop:currentLoop];
    UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:question message:@"\n" delegate:madelegate cancelButtonTitle:button1 otherButtonTitles:button2, nil];

    // Build text field
    UITextField *tf = [[UITextField alloc] initWithFrame:CGRectMake(0.0f, 0.0f, 260.0f, 30.0f)];
    tf.borderStyle = UITextBorderStyleRoundedRect;
    tf.tag = TEXT_FIELD_TAG;
    tf.placeholder = prompt;
    tf.clearButtonMode = UITextFieldViewModeWhileEditing;
    tf.keyboardType = UIKeyboardTypeAlphabet;
    tf.keyboardAppearance = UIKeyboardAppearanceAlert;
    tf.autocapitalizationType = UITextAutocapitalizationTypeWords;
    tf.autocorrectionType = UITextAutocorrectionTypeNo;
    tf.contentVerticalAlignment = UIControlContentVerticalAlignmentCenter;

    // Show alert and wait for it to finish displaying
    [alertView show];
    while (CGRectEqualToRect(alertView.bounds, CGRectZero));

    // Find the center for the text field and add it
    CGRect bounds = alertView.bounds;
    tf.center = CGPointMake(bounds.size.width / 2.0f, bounds.size.height / 2.0f - 10.0f);
    [alertView addSubview:tf];
    [tf release];

    // Set the field to first responder and move it into place
    [madelegate performSelector:@selector(moveAlert:) withObject:alertView afterDelay: 0.7f];

    // Start the run loop
    CFRunLoopRun();

    // Retrieve the user choices
    NSUInteger index = madelegate.index;
    NSString *answer = [[madelegate.text copy] autorelease];
    if (index == 0) answer = nil; // assumes cancel in position 0

    [alertView release];
    [madelegate release];
    return answer;
}

Thanks!

Answer 1

You should probably check whether a UITextField's userInteractionEnabled property defaults to YES or NO.