文章转自：http://www.cnblogs.com/wqxlcdymqc/p/3214414.html
http://www.cnblogs.com/iphone520/archive/2012/07/04/2575833.html
如果我们新老版本都要支持的话，那么还需要再加些东西进去。
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
if([self isViewLoaded] && self.view.window == nil)
{
self.view = nil;
}
sortedNames = nil;
sortedValues = nil;
}
我们往往还要支持低版本的，所以在程序中，我们就需要保留之前的方法。
但如果想要控制“UINavigationController”直接在Contoller中使用这个方法，将会不起作用，原因是ios6中“UINavigationController”并不支持
- (BOOL)shouldAutorotate、
- (NSUInteger)supportedInterfaceOrientations
个方法，如果您想要控制其旋转，必须为其添加一个category，使其支持这个三个方法。
@implementation UINavigationController (SupportIOS6)
-(BOOL)shouldAutorotate
{
return[[self.viewControllers lastObject] shouldAutorotate];
}
-(NSUInteger)supportedInterfaceOrientations
{
return[[self.viewControllers lastObject] supportedInterfaceOrientations];
}
- (UIInterfaceOrientation)preferredInterfaceOrientationForPresentation
{
return[[self.viewControllers lastObject] preferredInterfaceOrientationForPresentation];
}
@end
强制横竖屏的解决方案：
iOS6
让项目支持横竖屏 在具体页面 改变 supportedInterfaceOrientations
-(BOOL)shouldAutorotate
{
return YES;
}
-(NSUInteger)supportedInterfaceOrientations
{
return UIInterfaceOrientationMaskLandscapeRight; //这里写你需要的方向。看好了，别写错了
}
强制转成横屏:iOS5可用
if ([[UIDevice currentDevice] respondsToSelector:@selector(setOrientation:)]) {
SEL selector = NSSelectorFromString(@"setOrientation:");
NSInvocation *invocation = [NSInvocation invocationWithMethodSignature:[UIDevice instanceMethodSignatureForSelector:selector]];
[invocation setSelector:selector];
[invocation setTarget:[UIDevice currentDevice]];
int val = UIInterfaceOrientationLandscapeRight;
[invocation setArgument:&val atIndex:2];
[invocation invoke];
}
方法二： 通过判断状态栏来设置视图的transform属性。
- (void)deviceOrientationDidChange: (NSNotification *)notification
{
UIInterfaceOrientation interfaceOrientation = [[UIApplication sharedApplication] statusBarOrientation];
CGFloat startRotation = [[self valueForKeyPath:@"layer.transform.rotation.z"] floatValue];
CGAffineTransform rotation;
switch (interfaceOrientation) {
case UIInterfaceOrientationLandscapeLeft:
rotation = CGAffineTransformMakeRotation(-startRotation + M_PI * 270.0 / 180.0);
break;
case UIInterfaceOrientationLandscapeRight:
rotation = CGAffineTransformMakeRotation(-startRotation + M_PI * 90.0 / 180.0);
break;
case UIInterfaceOrientationPortraitUpsideDown:
rotation = CGAffineTransformMakeRotation(-startRotation + M_PI * 180.0 / 180.0);
break;
default:
rotation = CGAffineTransformMakeRotation(-startRotation + 0.0);
break;
}
view.transform = rotation;
}