当应用程序面向横向和纵向时，更改不同的 self.view.backgroundColor 图像

Question

- (void) didRotateFromInterfaceOrientation:(UIInterfaceOrientation)fromInterfaceOrientation{
    if ((fromInterfaceOrientation == UIInterfaceOrientationPortrait) || (fromInterfaceOrientation == UIInterfaceOrientationPortraitUpsideDown)) {
        self.view.backgroundColor=[UIColor colorWithPatternImage:[UIImage imageNamed:@"bgImage.png"]];
    }
    else
    {
        self.view.backgroundColor=[UIColor colorWithPatternImage:[UIImage imageNamed:@"bgImage1.png"]];
    }
}

我使用上面的代码在设备面向横向或纵向时设置self.view.backgroundColor图像。图像正确更改。

问题：

1. 当我尝试旋转设备时，图像不会快速变化，我的意思是更改图像需要 2 到 3 秒。

2. 如何根据横向或纵向首次设置self.view.backgroundColor图像。

Answer 1

请尝试以下操作：

答案1：以VC willRotateToInterfaceOrientation:duration:方法进行操作。此方法是在界面方向更改时调用的动画方法，它将在背景图像之间提供平滑过渡。

答案 2：使用所需的映像设置self.view.backgroundColor，viewWillAppear:animated:方法中考虑self.interfaceOrientation，这反映了 VC 的当前接口方向。

理想情况下，您可以创建如下方法：

-(void)setBackgroundForInterfaceOrientation:(UIInterfaceOrientation)orientation {
    if (UIInterfaceOrientationIsLandscape(orientation)) {
        self.view.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:@"bg-iphone3-landscape"]];
    }
    else {
        self.view.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:@"bg-iphone3"]];
    }
}

现在从任一位置调用此方法：

-(void)willRotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration {
    [self setBackgroundForInterfaceOrientation:toInterfaceOrientation];
}
-(void)viewWillAppear:(BOOL)animated {
    [super viewWillAppear:animated];
    [self setBackgroundForInterfaceOrientation:self.interfaceOrientation];
}

希望对您有所帮助。

Answer 2

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view.
    UIDeviceOrientation currentOrientation = [UIApplication sharedApplication].statusBarOrientation;
    if (currentOrientation == UIInterfaceOrientationLandscapeLeft
        ||  currentOrientation == UIInterfaceOrientationLandscapeRight)
    {
        [imageview setImage:[UIImage imageNamed:@"backgroundImage.png"]];
    }
    else
    {
        [imageview setImage:[UIImage imageNamed:@"Portrait-backgroundImage.png"]];
    }
}

Answer 3

使用它

     -(void)viewWillAppear:(BOOL)animated
       {
          [self willAnimateRotationToInterfaceOrientation:[UIApplication sharedApplication].statusBarOrientation duration:1.0];
        }

     -(void)willAnimateRotationToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation
                                     duration:(NSTimeInterval)duration
      {
        if (toInterfaceOrientation == UIInterfaceOrientationLandscapeLeft || toInterfaceOrientation == UIInterfaceOrientationLandscapeRight)
          {
              self.view.backgroundColor=[UIColor colorWithPatternImage:[UIImage imageNamed:@"bgImage1.png"]];
          }
        else if (toInterfaceOrientation == UIInterfaceOrientationPortrait || (toInterfaceOrientation==UIInterfaceOrientationPortraitUpsideDown))
          {
             self.view.backgroundColor=[UIColor colorWithPatternImage:[UIImage imageNamed:@"bgImage.png"]];
          }
       }