通过在顶部添加以下View，我设法获得了灰度的UIView:@interfaceGreyscaleAllView:UIView@property(nonatomic,retain)UIView*underlyingView;@end@implementationGreyscaleAllView@synthesizeunderlyingView;-(void)drawRect:(CGRect)rect{CGContextRefcontext=UIGraphicsGetCurrentContext();//drawtheimage[self.underlyingView.layerrend