Question

当方向改变时，我想更改视图控制器的背景图片。我在shouldAutorotateToInterfaceOrientation中调用了setupGUIForOrientation函数，如下所示：

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
    [self setupGUIForOrientation:interfaceOrientation];
    return YES;
}

setupGUIForOrientation函数：

-(void)setupGUIForOrientation:(UIInterfaceOrientation)orientation
{
    if(!background) background = [[UIImageView alloc] init];
    UIImage* image = [[StorageProvider storage].imageProvider getImageForSurfaceElement:@"background"];
    int width = 0;
    int height = 0;
    CGRect bounds = [[UIScreen mainScreen] bounds];
    if(UIInterfaceOrientationIsPortrait(orientation)) {
        width = MIN(bounds.size.width, bounds.size.height);
        height = MAX(bounds.size.width, bounds.size.height);
    } else {
        width = MAX(bounds.size.width, bounds.size.height);
        height = MIN(bounds.size.width, bounds.size.height);
    }
    background.frame = CGRectMake(0, 0, width, height);
    [self.view addSubview: background];
    [self.view sendSubviewToBack: background];
    [background setImage:image];
}

一切都很好（图像和框架改变）除了一件事：当旋转发生时，我可以看到视图控制器的背景颜色一秒钟，这真的很难看。我可以以某种方式阻止它吗？而且，我可以更好地编写此功能吗？谢谢你的帮助！

Answer 1

我猜，但你可能会过早更新你的观点。不是在shouldAutorotateToInterfaceOrientation中调用您的方法，您是否尝试在didRotateFromInterfaceOrientation中执行此操作？

即。做出这样的改变：

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
    return YES;
}
- (void)didRotateFromInterfaceOrientation:(UIInterfaceOrientation)fromInterfaceOrientation
{
    [self setupGUIForOrientation:self.interfaceOrientation];
}

当屏幕方向改变时，背景图片“闪烁”

1 个答案: