UIViewController 自动旋转一些组件？答案

【问题标题】：UIViewController autorotate some components?UIViewController 自动旋转一些组件？
【发布时间】：2011-08-16 03:32:34
【问题描述】：

我有一个 UIViewController，它有一个图像视图和一个工具栏。我希望工具栏旋转，但图像视图保持原样。这可能吗？

【问题讨论】：

是什么触发了轮换？设备方向、设备指南针等？

标签： iphone uiviewcontroller rotation autorotate

【解决方案1】：

是的，这是可能的，但需要手动处理旋转事件。

在viewDidLoad中，添加

// store the current orientation
currentOrientation = UIInterfaceOrientationPortrait;
[[UIDevice currentDevice] beginGeneratingDeviceOrientationNotifications];
[[NSNotificationCenter defaultCenter] addObserver:self selector: @selector(receivedRotate:) name: UIDeviceOrientationDidChangeNotification object: nil];

if(currentOrientation != self.interfaceOrientation) {
    [self deviceInterfaceOrientationChanged:self.interfaceOrientation];
}

并且不要忘记在移除控制器时取消注册事件。然后添加一个旋转的方法：

// This method is called by NSNotificationCenter when the device is rotated.
-(void) receivedRotate: (NSNotification*) notification
{
    NSLog(@"receivedRotate");
    UIDeviceOrientation interfaceOrientation = [[UIDevice currentDevice] orientation];

    if(interfaceOrientation != UIDeviceOrientationUnknown) {
        [self deviceInterfaceOrientationChanged:interfaceOrientation];
    } else {
        NSLog(@"Unknown device orientation");
    }
}

最后是旋转方法

- (void)deviceInterfaceOrientationChanged:(UIInterfaceOrientation)interfaceOrientation {

    if(interfaceOrientation == currentOrientation) {
        NSLog(@"Do not rotate to current orientation: %i", interfaceOrientation);
    } else if(interfaceOrientation == UIInterfaceOrientationPortraitUpsideDown) {
        NSLog(@"Do not rotate to UIInterfaceOrientationPortraitUpsideDown");
    } else if(interfaceOrientation == UIInterfaceOrientationLandscapeLeft) {
        NSLog(@"Do not rotate to UIInterfaceOrientationLandscapeLeft");
    } else {

        if(!isRotating)
        {
            isRotating = YES;

            if(currentOrientation ==  UIInterfaceOrientationPortrait && interfaceOrientation == UIInterfaceOrientationLandscapeRight) {
                NSLog(@"Rotate to landscape");

                // rotate to right top corner
                [UIView beginAnimations:nil context:NULL];
                [UIView setAnimationDuration:0.5];

                // do your rotation here

                [UIView setAnimationDelegate:self];
                [UIView setAnimationDidStopSelector:@selector(animationDoneShowCaption:finished:context:)];
                [UIView commitAnimations];


            } else if(currentOrientation == UIInterfaceOrientationLandscapeRight && interfaceOrientation == UIInterfaceOrientationPortrait) {
                // etc
            }

            isRotating = NO;
        } else {
            NSLog(@"We are already rotating..");
        }
    }

    currentOrientation = interfaceOrientation;
}

请注意，我不允许在某些方向上旋转，您可能会这样做。

此外，您需要使您的组件可调整大小/能够旋转。

编辑考虑改用block-based动画并在完成块中设置isRotation = NO。

【讨论】：