iPhone：如何使用NSTimer隐藏UIButton并拍摄屏幕截图

Question

您好如何在隐藏UIButton后实现NSTimer进行屏幕截图，您能告诉我如何使用EXAMPLE实现它。 首先UIButton必须隐藏和屏幕截图必须采取屏幕有一个美好的一天

Answer 1

以下是如何获取窗口的屏幕截图：

http://fmwebschool.com/blog/2008/10/01/taking-screenshots-with-the-iphone-sdk/

对于其余的：

[NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:@selector(count) userInfo:nil repeats:YES];

- (void)count {
counter++;
if (counter == secondsToWait) {
button.alpha = 0;
//Take Screenshot here
}
}

Answer 2

要在给定时间截取屏幕特定部分的屏幕截图，请使用类似的内容

CGRect screenRect = CGRectMake(0, 0, 200, 200);
UIGraphicsBeginImageContext(screenRect.size);

CGContextRef ctx = UIGraphicsGetCurrentContext();
CGContextFillRect(ctx, screenRect);
//you probably need an offset, adjust here
CGContextTranslateCTM(ctx, -20, -20);
[self.view.layer renderInContext:ctx];

UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();

//if you want to save this image to the photo album uncomment the next line
//UIImageWriteToSavedPhotosAlbum(newImage, nil, nil, nil);
UIGraphicsEndImageContext();

在一个名为takePhoto的方法中包装所有这些，你可以使用NSTimer来触发

[NSTimer scheduledTimerWithTimeInterval:5.0 target:self selector:@selector(takePhoto:) userInfo:nil repeats:YES];