UIGestureRecognizer 通过后如何保存 UIImageView？

Question

我有一个带有 2 个 UIImageView 的应用程序，它们相互重叠。我有 backgroundImg 和 FrontImg。其中 frontImg 可以：通过 UIGestureRecognizers 旋转、移动、缩放。

当我想保存我的 UIImages 时，我会合并它们，但它们会被保存，就好像它们从未被触摸过一样。

有谁知道如何解决这个问题？

这是我的保存方法： UIGraphicsBeginImageContext(self.backgroundImg.image.size);

    CGRect rect = CGRectMake(0, 0, self.backgroundImg.image.size.width, self.backgroundImg.image.size.height);
    self.frontImg.contentMode = UIViewContentModeScaleAspectFit;
    [self.backgroundImg.image drawInRect:rect];
    [self.frontImg.image drawInRect:rect];

    UIImage *resultingImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();

    //[imageView3 setImage:resultingImage];

    UIGraphicsBeginImageContextWithOptions(self.backgroundImg.bounds.size, NO,0.0);
    [self.backgroundImg.image drawInRect:CGRectMake(0, 0, self.backgroundImg.frame.size.width, self.backgroundImg.frame.size.height)];
    //UIImage *SaveImage = UIGraphicsGetImageFromCurrentImageContext();
    //UIImage *resultingImage = [self mergeImage:self.backgroundImg.image withImage:self.frontImg.image];
    UIGraphicsEndImageContext();
    UIImageWriteToSavedPhotosAlbum(resultingImage, self,@selector(image:didFinishSavingWithError:contextInfo:), nil);

这些是我的手势功能：

-(IBAction)handlePan:(UIPanGestureRecognizer *)recognizer{
    CGPoint translation = [recognizer translationInView:self.view];
    recognizer.view.center = CGPointMake(recognizer.view.center.x + translation.x,
                                         recognizer.view.center.y + translation.y);
    [recognizer setTranslation:CGPointMake(0, 0) inView:self.view];
}

-(IBAction)handlePinch:(UIPinchGestureRecognizer *)recognizer
{
    recognizer.view.transform = CGAffineTransformScale(recognizer.view.transform, recognizer.scale, recognizer.scale);
    recognizer.scale =1;
}

-(BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer{
    return ![gestureRecognizer isKindOfClass:[UIPanGestureRecognizer class]];
}

-(IBAction)handleRotate:(UIRotationGestureRecognizer *)recognizer
{
    recognizer.view.transform = CGAffineTransformRotate(recognizer.view.transform, recognizer.rotation);
    self.frontImg.transform = CGAffineTransformRotate(recognizer.view.transform, recognizer.rotation);
    recognizer.rotation = 0;
}

Answer 1

您的正面图像未按照视图中的坐标、比例等绘制。您正在使用与背景相同的矩形（0、0、backgroundWidth、backgroundHeight）来绘制它。您需要确保在将其绘制到图形上下文时获得正确的位置、大小和比例。

如果两个图像都包含在同一个视图中，您可以截取该视图。这篇文章应该可以帮助你：http://ios-dev-blog.com/how-to-create-uiimage-from-uiview/