iphone - 从两个 UIImageView 创建一个 UIImage

Question

我的UIView上有两个UIImageView。每个 UIImageView 有一个 UIImage。现在我想从两个 UIImageView 创建一个 UIImage。

请给我建议，我该怎么做。

Answer 1

如果您有一个包含三个 UIImageView 的 View 并创建相应的导出

IBOutlet UIImageView *imageView1;
IBOutlet UIImageView *imageView2;
IBOutlet UIImageView *imageView3;

您可以执行类似以下操作将 imageView 1 和 2 合并到 imageView 3

UIGraphicsBeginImageContext(imageView1.image.size);  

CGRect rect = CGRectMake(0, 0, imageView1.image.size.width, imageView1.image.size.height);

[imageView1.image drawInRect:rect];  
[imageView2.image drawInRect:rect blendMode:kCGBlendModeScreen alpha:0.5];  

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

[imageView3 setImage:resultingImage];

CGBlendMode 允许您为图像选择以下任何合成操作:

enum CGBlendMode {
   kCGBlendModeNormal,
   kCGBlendModeMultiply,
   kCGBlendModeScreen,
   kCGBlendModeOverlay,
   kCGBlendModeDarken,
   kCGBlendModeLighten,
   kCGBlendModeColorDodge,
   kCGBlendModeColorBurn,
   kCGBlendModeSoftLight,
   kCGBlendModeHardLight,
   kCGBlendModeDifference,
   kCGBlendModeExclusion,
   kCGBlendModeHue,
   kCGBlendModeSaturation,
   kCGBlendModeColor,
   kCGBlendModeLuminosity,
   kCGBlendModeClear,
   kCGBlendModeCopy,
   kCGBlendModeSourceIn,
   kCGBlendModeSourceOut,
   kCGBlendModeSourceAtop,
   kCGBlendModeDestinationOver,
   kCGBlendModeDestinationIn,
   kCGBlendModeDestinationOut,
   kCGBlendModeDestinationAtop,
   kCGBlendModeXOR,
   kCGBlendModePlusDarker,
   kCGBlendModePlusLighter
};