Question

我想调用一个截取屏幕截图然后将此屏幕截图作为子视图加载的方法。我正在使用苹果示例代码来了解如何拍摄屏幕截图（见下文）并尝试在我的代码中使用结果（图像）。但是，我真的不知道如何将方法中的图像转换为我的代码。这就是我的尝试;这显然是错的，但这是我能想到的全部：

    // Test Screenshot:

screenShot = [UIImage screenshot]; // THIS DOESN'T WORK
screenShotView = [[UIImageView alloc] initWithImage:screenShot];
[screenShotView setFrame:CGRectMake(0, 0, 320, 480)];
[self.view addSubview:screenShotView];

这是Apple的方法示例代码：

 - (UIImage*)screenshot 
{
    NSLog(@"Shot");

    // Create a graphics context with the target size
    // On iOS 4 and later, use UIGraphicsBeginImageContextWithOptions to take the scale into consideration
    // On iOS prior to 4, fall back to use UIGraphicsBeginImageContext
    CGSize imageSize = [[UIScreen mainScreen] bounds].size;
    if (NULL != UIGraphicsBeginImageContextWithOptions)
        UIGraphicsBeginImageContextWithOptions(imageSize, NO, 0);
    else
        UIGraphicsBeginImageContext(imageSize);

    CGContextRef context = UIGraphicsGetCurrentContext();

    // Iterate over every window from back to front
    for (UIWindow *window in [[UIApplication sharedApplication] windows]) 
    {
        if (![window respondsToSelector:@selector(screen)] || [window screen] == [UIScreen mainScreen])
        {
            // -renderInContext: renders in the coordinate space of the layer,
            // so we must first apply the layer's geometry to the graphics context
            CGContextSaveGState(context);
            // Center the context around the window's anchor point
            CGContextTranslateCTM(context, [window center].x, [window center].y);
            // Apply the window's transform about the anchor point
            CGContextConcatCTM(context, [window transform]);
            // Offset by the portion of the bounds left of and above the anchor point
            CGContextTranslateCTM(context,
                                  -[window bounds].size.width * [[window layer] anchorPoint].x,
                                  -[window bounds].size.height * [[window layer] anchorPoint].y);

            // Render the layer hierarchy to the current context
            [[window layer] renderInContext:context];

            // Restore the context
            CGContextRestoreGState(context);
        }
    }

    // Retrieve the screenshot image
    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();

    UIGraphicsEndImageContext();

    return image;
}

非常感谢任何帮助！感谢。

编辑：这是viewDidLoad方法，我在其中创建一个TextView，然后尝试捕获它的屏幕截图：

    - (void)viewDidLoad {


    // Setup TextView:

    NSString* someText = @"Some Text";
    CGRect frameText = CGRectMake(0, 0, 320, 480); 
    aTextView = [[UITextView alloc] initWithFrame:frameText];
    aTextView.text = someText;  
[self.view addSubview:aTextView];


    // Test Screenshot:

    screenShotView = [[UIImageView alloc] initWithImage:[self screenshot]];
    [screenShotView setFrame:CGRectMake(10, 10, 200, 200)];
    [self.view addSubview:screenShotView];

    [self.view bringSubviewToFront:screenShotView];

    [super viewDidLoad];



}

Answer 1

要使用图像，只需更改此行

即可

screenShot = [UIImage screenshot];

要

screenShot = [self screenshot];

编辑：检查[自我屏幕截图]是否返回有效图像或无。

   - (void)viewDidLoad {


    // Setup TextView:

    NSString* someText = @"Some Text";
    CGRect frameText = CGRectMake(0, 0, 320, 480); 
    aTextView = [[UITextView alloc] initWithFrame:frameText];
    aTextView.text = someText;  
    [self.view addSubview:aTextView];


    // Test Screenshot:

    UIImage *screenShotImage = [self screenShot];
    if(screenShot){
            screenShotView = [[UIImageView alloc] initWithImage:screenShotImage];
            [screenShotView setFrame:CGRectMake(10, 10, 200, 200)];
            [self.view addSubview:screenShotView];

            [self.view bringSubviewToFront:screenShotView];
    }else
         NSLog(@"Something went wrong in screenShot method, the image is nil");

    [super viewDidLoad];



}

iPhone：以编程方式创建屏幕截图，然后将其添加为子视图

1 个答案: