更改UIImage颜色

利用image属性renderingMode

1. UIImageRenderingModeAutomatic  // 根据图片的使用环境和所处的绘图上下文自动调整渲染模式。  
2. UIImageRenderingModeAlwaysOriginal   // 始终绘制图片原始状态，不使用Tint Color。  
3. UIImageRenderingModeAlwaysTemplate   // 始终根据Tint Color绘制图片，忽略图片的颜色信息。  

根据Tint Color修改颜色

   UIButton *clearButton = [[ UIButton alloc ] initWithFrame : CGRectMake ( 0 , 0 , 44 , 44 )];

   clearButton.tintColor =[UIColorblackColor];

   UIImage *image =[UIImageimageNamed:@"delete"];

   image=[image imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate];

   [clearButton setImage:imageforState:UIControlStateNormal];

iOS7以上可用。

也可以重写UIImage

//改变图片颜色

- (UIImage *)imageWithColor:(UIColor *)color
{
UIGraphicsBeginImageContextWithOptions(self.size, NO, self.scale);
CGContextRefcontext = UIGraphicsGetCurrentContext();
CGContextTranslateCTM(context, 0, self.size.height);
    CGContextScaleCTM(context, 1.0, -1.0);
CGContextSetBlendMode(context, kCGBlendModeNormal);
    CGRect rect = CGRectMake(0, 0, self.size.width, self.size.height);
    CGContextClipToMask(context, rect, self.CGImage);
    [color setFill];
    CGContextFillRect(context, rect);
UIImage*newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
    return newImage;
}

UIColor 转UIImage 根据上下文

- (UIImage*) createImageWithColor: (UIColor*) color  

{  

    CGRect rect=CGRectMake(0,0, 1, 1); 

    UIGraphicsBeginImageContext(rect.size);  

    CGContextRef context = UIGraphicsGetCurrentContext();   

    CGContextSetFillColorWithColor(context, [color CGColor]);

    CGContextFillRect(context, rect);  

    UIImage *theImage = UIGraphicsGetImageFromCurrentImageContext();

    UIGraphicsEndImageContext();  

    return theImage;  

}  

UIImage转UIColor 

[UIColor colorWithPatternImage:[UIImageimageNamed:@“bg.png"]]