ios - 屏幕方向改变时背景图片为 "blinking"

Question

当方向改变时，我想改变 View Controller 的背景图片。我在 shouldAutorotateToInterfaceOrientation 中调用 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(图像和框架发生变化)，除了一件事:当旋转发生时，我可以看到 View Controller 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，我可以用更好的方式编写这个函数吗？感谢您的帮助!

Answer 1

我猜，但您可能太早更新了您的 View 。您是否尝试过在 didRotateFromInterfaceOrientation 中调用您的方法，而不是在 shouldAutorotateToInterfaceOrientation 中调用您的方法？

即进行此更改:

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