UIImage分类-圆角、纯色图片、带圆角的纯色图片

开发中,可能会使用到圆角图片,如果直接设置ImageView的layer属性,会提前开启屏幕渲染到离屏渲染,消耗性能,通过UIImage分类的方式,实现创建纯色图片、创建带圆角的纯色图片、设置圆角图片以及生成带圆环的圆角图片四个方法

.h

#import 

@interface UIImage (Color)

/**
 *  创建纯色图片
 *
 *  @param color     生成纯色图片的颜色
 *  @param imageSize 需要创建纯色图片的尺寸
 *
 *  @return 纯色图片
 */
+ (UIImage *)js_createImageWithColor:(UIColor *)color withSize:(CGSize)imageSize;
/**
 *  创建圆角图片
 *
 *  @param originalImage 原始图片
 *
 *  @return 带圆角的图片
 */
+ (UIImage *)js_imageWithOriginalImage:(UIImage *)originalImage;
/**
 *  创建圆角纯色图片
 *
 *  @param color     设置圆角纯色图片的颜色
 *  @param imageSize 设置元角纯色图片的尺寸
 *
 *  @return 圆角纯色图片
 */
+ (UIImage *)js_createRoundedImageWithColor:(UIColor *)color withSize:(CGSize)imageSize;
/**
 *  生成带圆环的圆角图片
 *
 *  @param originalImage 原始图片
 *  @param borderColor   圆环颜色
 *  @param borderWidth   圆环宽度
 *
 *  @return 带圆环的圆角图片
 */
+ (UIImage *)js_imageWithOriginalImage:(UIImage *)originalImage withBorderColor:(UIColor *)borderColor withBorderWidth:(CGFloat)borderWidth;
@end

.m

#import "UIImage+Color.h"

@implementation UIImage (Color)

// 生成纯色图片
+ (UIImage *)js_createImageWithColor:(UIColor *)color withSize:(CGSize)imageSize{
    
    CGRect rect = CGRectMake(0.0f, 0.0f, imageSize.width, imageSize.height);
    
    UIGraphicsBeginImageContextWithOptions(imageSize, NO, 0.0);
    
    CGContextRef context = UIGraphicsGetCurrentContext();
    
    CGContextSetFillColorWithColor(context, color.CGColor);
    
    CGContextFillRect(context, rect);
    
    UIImage *resultImage = UIGraphicsGetImageFromCurrentImageContext();
    
    UIGraphicsEndImageContext();
    
    return resultImage;
}

// 生成圆角图片
+ (UIImage *)js_imageWithOriginalImage:(UIImage *)originalImage{
    
    CGRect rect = CGRectMake(0, 0, originalImage.size.width, originalImage.size.height);
    
    UIGraphicsBeginImageContextWithOptions(originalImage.size, NO, 0.0);
    
    CGFloat cornerRadius = MIN(originalImage.size.width, originalImage.size.height) * 0.5;
    
    [[UIBezierPath bezierPathWithRoundedRect:rect
                                cornerRadius:cornerRadius] addClip];
    
    [originalImage drawInRect:rect];
    
    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
    
    UIGraphicsEndImageContext();
    
    return image;
}

// 生成纯色圆角图片
+ (UIImage *)js_createRoundedImageWithColor:(UIColor *)color withSize:(CGSize)imageSize{
    
    UIImage *originalImage = [self js_createImageWithColor:color withSize:imageSize];
    
    return [self js_imageWithOriginalImage:originalImage];
}
// 生成带圆环的圆角图片
+ (UIImage *)js_imageWithOriginalImage:(UIImage *)originalImage withBorderColor:(UIColor *)borderColor withBorderWidth:(CGFloat)borderWidth{
    
    
    CGRect rect = CGRectMake(0, 0, originalImage.size.width, originalImage.size.height);
    
    UIGraphicsBeginImageContextWithOptions(originalImage.size, NO, 0.0);
    
    CGFloat cornerRadius = MIN(originalImage.size.width, originalImage.size.height) * 0.5;
    
    [[UIBezierPath bezierPathWithRoundedRect:rect
                                cornerRadius:cornerRadius] addClip];
    
    
    [originalImage drawInRect:rect];
    
    CGPoint center = CGPointMake(originalImage.size.width * 0.5, originalImage.size.height * 0.5);
    
    UIBezierPath *circlePath = [UIBezierPath bezierPathWithArcCenter:center radius:cornerRadius - borderWidth*0.5 startAngle:0 endAngle:M_PI * 2 clockwise:YES];
    circlePath.lineWidth = borderWidth;
    [borderColor setStroke];
    [circlePath stroke];
    
    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
    
    UIGraphicsEndImageContext();
    
    return image;
    
    
}
@end