Guys, need your advise here. I have: an UIViewController A UIView B: I added subview which is a UIView to the UIViewController A an UIViewController C What I did is: in UIViewController A's viewDidLoad's method, I call this: UIView *subviewB = [[Subview alloc] initWithFrame:CGRectMake(0, 0, 1024, 768)]; [subviewB subviewBMethod]; // [self.view addSubview:rsubviewB]; SubviewBMethod code is to create an view, inside this view have a button. Once this button is clicked, it will change to UIViewController C. I tried this: [self presentModalViewController:self.UIViewControllerC animated:YES]; And I got this error message: warning: incompatible Objective-C types 'struct UIViewControllerC *', expected 'struct UIViewController *' when passing argument 1 of 'presentModalViewController:animated:' from distinct Objective-C type When I run the app, it terminates immediately when I click the button, I opened the console bug, there is no any error message. My method must be wrong, thus my question is: Issit possible to load a UIVIewcontroller from uiview of another UIViewController? If: Yes: How to do it? No: What should I do? THank you =)