Errata for Chapter 7, project ScreenRotations

weimenglee · February 11th, 2012, 11:31 AM

In Chapter 7, in the project ScreenRotations, the positionViews: method should have an additional parameter and the first line commented out:

Code:

-(void) positionViews:(UIInterfaceOrientation) destOrientation {    
    // UIInterfaceOrientation destOrientation = self.interfaceOrientation; 
    if (destOrientation == UIInterfaceOrientationPortrait ||
        destOrientation == UIInterfaceOrientationPortraitUpsideDown) {
        //â-if rotating to portrait modeâ-
        btn.frame = CGRectMake(20, 20, 233, 37);
    } else {        
        //â-if rotating to landscape modeâ-
        btn.frame = CGRectMake(227, 243, 233, 37);
    }       
}

So, when calling the positionViews: method, you should call it with the destination orientation:

Code:

-(void)willRotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation 
                               duration:(NSTimeInterval)duration {
    [self positionViews:toInterfaceOrientation];
}

Finally, in the viewDidLoad method, call the positionViews: method with the current destination:

Code:

- (void)viewDidLoad
{
    [self positionViews:[[UIApplication sharedApplication] statusBarOrientation]];
    [super viewDidLoad];
}

The original code in the book works when using the positionView method with the willAnimateSecondHalfOfRotationFromInterfaceOrient ation: method. However, since the latter method is deprecated, you need to manually pass in the destination orientation to the positionViews method.

wel51x · May 14th, 2012, 08:51 PM

...use the willAnimateRotationToInterfaceOrientation: method (instead of, as pointed out here, the willAnimateSecondHalfOfRotationFromInterfaceOrient ation: method).