固定形状自己填充自定义颜色图

因要根据电量 显示不同的颜色，且图片形状一样，切图多了。太不人性化了
想到用图像混合，给个底图，想要什么颜色图自己混合颜色。

BlendMode kCGBlendModeMultiply 说明：正片叠底；混合了前景和背景的颜色，最终颜色比原先的都暗;

底图白色边框，里面自己用层动态画出来。我们将要渲染的是边框

简单扩展一下UIImage ，使用起来也简单 

[self.imageViewBattery setImage:[[UIImage imageNamed:@"battery_back_tintcolour"]imageWithMultiplyTintColor:colorBattery]];

以下是扩展代码

#import

@interface UIImage (Tint)

- (UIImage *)imageWithMultiplyTintColor:(UIColor *)tintColor;

@end

#import "UIImage+Tint.h"

@implementation UIImage (Tint)

- (UIImage*)imageWithTintColor:(UIColor*)tintColor blendMode:(CGBlendMode)blendMode

{

    //We want to keep alpha, set opaque to NO; Use 0.0f for scale to use the scale factor of the device’s main screen.

    UIGraphicsBeginImageContextWithOptions(self.size, NO, 0.0f);

    [tintColor setFill];

    CGRect bounds = CGRectMake(0, 0, self.size.width, self.size.height);

    UIRectFill(bounds);

    //Draw the tinted image in context

    [self drawInRect:boundsblendMode:blendModealpha:1.0f];

    if (blendMode != kCGBlendModeDestinationIn) {

        [self drawInRect:bounds blendMode:kCGBlendModeDestinationIn alpha:1.0f];

    }

    UIImage *tintedImage = UIGraphics GetImageFromCurrentImageContext();

    UIGraphicsEndImageContext();

    returntintedImage;

}

-(UIImage * )imageWithMultiplyTintColor:(UIColor *)tintColor

{

    return [self imageWithTintColor:tintColor blendMode:kCGBlendModeMultiply];

}

@end

需要注意的是底图非填充部分采用透明色