changes subView frame when rotate

Question

i add subView(backgroundView) in uiview in my base view controller its working well in potratate but when i change orientation from potraite to landscape its frame size is same as potrait i want to change size of subview when rotate.

UIView *activityView = [[UIView alloc] initWithFrame:self.view.bounds];
CGRect frame = activityView.frame;
activityView.frame = frame;
activityView.backgroundColor = [UIColor clearColor];
activityView.alpha = 0.0f;
[self.view addSubview:activityView];
self.activityView = activityView;
UIView *backgroundView = [[UIView alloc]initWithFrame:activityView.bounds];
backgroundView.alpha = 0.0f;
[backgroundView setBackgroundColor:[UIColor lightGrayColor]];
[self.activityView backgroundView];
UIActivityIndicatorView *spinning = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
[self.activityView spinning];
spinning.center = activityView.center;
self.activityView.autoresizingMask = UIViewAutoresizingFlexibleLeftMargin | UIViewAutoresizingFlexibleTopMargin | UIViewAutoresizingFlexibleRightMargin | UIViewAutoresizingFlexibleBottomMargin;
[spinning setColor:[UIColor lightGrayColor]];
[spinning startAnimating];

Answer 1

To do this you must add constraints to your view (AutoLayout).

For example :

[self.view addConstraint:[NSLayoutConstraint constraintWithItem:containerView
                                                      attribute:NSLayoutAttributeTop
                                                      relatedBy:NSLayoutRelationEqual
                                                         toItem:self.view
                                                      attribute:NSLayoutAttributeTop
                                                     multiplier:1.0
                                                       constant:0.0]];

[self.view addConstraint:[NSLayoutConstraint constraintWithItem:containerView
                                                      attribute:NSLayoutAttributeLeading
                                                      relatedBy:NSLayoutRelationEqual
                                                         toItem:self.view
                                                      attribute:NSLayoutAttributeLeading
                                                     multiplier:1.0
                                                       constant:0.0]];

[self.view addConstraint:[NSLayoutConstraint constraintWithItem:containerView
                                                      attribute:NSLayoutAttributeBottom
                                                      relatedBy:NSLayoutRelationEqual
                                                         toItem:self.view
                                                      attribute:NSLayoutAttributeBottom
                                                     multiplier:1.0
                                                       constant:0.0]];

[self.view addConstraint:[NSLayoutConstraint constraintWithItem:containerView
                                                      attribute:NSLayoutAttributeTrailing
                                                      relatedBy:NSLayoutRelationEqual
                                                         toItem:self.view
                                                      attribute:NSLayoutAttributeTrailing
                                                     multiplier:1.0
                                                       constant:0.0]];

Edit :

Don't forget to set translatesAutoresizingMaskIntoConstraints property to NO on views.

(Replace self.view and containerView with your views).