在以编程方式进行屏幕截图时，uiimage并未保存

Question

我正在尝试使用：

进行屏幕截图

if ([[UIScreen mainScreen] respondsToSelector:@selector(scale)]) {
    UIGraphicsBeginImageContextWithOptions(self.contentView.bounds.size, NO, [UIScreen mainScreen].scale);
} else {
    UIGraphicsBeginImageContext(self.contentView.bounds.size);
}
[self.contentView.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();

但是，保存的图像不包含屏幕截图中的图像（改为显示白色）。为什么这是？

任何帮助。

Answer 1

尝试此

if ([[UIScreen mainScreen] respondsToSelector:@selector(scale)]) {
    UIGraphicsBeginImageContextWithOptions(self.image.bounds.size, NO, 2.0);
} else {
    UIGraphicsBeginImageContext(self.image.bounds.size);
}
[self.image drawViewHierarchyInRect:self.image.bounds afterScreenUpdates:YES];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
NSData *imageData = UIImagePNGRepresentation(image);
if (imageData) {
    [imageData writeToFile:@"screenshot.png" atomically:YES];
} else {
    NSLog(@"error while taking screenshot");
}