Two-way event response (Viewwilllayoutsubviews and notifications)

Reprint: http://blog.csdn.net/nogodoss/article/details/17246489

Recently the screen, get some experience, special record down.

The most important thing is to determine the interface of the screen response. There are two ways I know now:

1. Use notifications.

-(void) Viewdidload

{

[[Nsnotificationcenter defaultcenter] addobserver:self selector:@selector(_ Orientationdidchange:) name: Uideviceorientationdidchangenotification object:nil];

}

-(void) Dealloc {

[[Nsnotificationcenter defaultcenter] removeobserver:self name: UideviceorientationdidchangenotificationObject:nil];

}

-(void) _orientationdidchange: (nsnotification*) notify

{

[self _shouldrotatetoorientation:(uideviceorientation] [uiapplication sharedapplication ].statusbarorientation];

}

-(void) _shouldrotatetoorientation: (uideviceorientation) Orientation {

If (orientation = = Uideviceorientationportrait | | Orientation = = Uideviceorientationportraitupsidedown) {

Vertical screen

}

else {

Horizontal screen

}

}

The above code, a look will understand.

2. Using Viewwilllayoutsubviews

When the test finds the screen switching, the system responds to some functions, one of which is viewwilllayoutsubviews.

-(void) viewwilllayoutsubviews

{

[self _shouldrotatetoorientation:(uideviceorientation] [uiapplication Sharedapplication].statusbarorientation];

}

Through one of the above functions, we know the interface of the screen switching.

Attention:

Viewwilllayoutsubviews can only be used in Viewcontroller, there is no response in view.

Two-way event response (Viewwilllayoutsubviews and notifications)