iOS 渐变色

UIColor (ChangingColor)

.h文件

//绘制渐变色颜色的方法

+ (UIImage*)setGradualChangingColor:(UIView*)view fromColor:(NSString*)fromHexColorStr toColor:(NSString*)toHexColorStr;

.m文件

//绘制渐变色颜色的方法

+ (UIImage*)setGradualChangingColor:(UIView*)view fromColor:(NSString*)fromHexColorStr toColor:(NSString*)toHexColorStr{

    //    CAGradientLayer类对其绘制渐变背景颜色、填充层的形状(包括圆角)

    CAGradientLayer *gradientLayer = [CAGradientLayer layer];

    gradientLayer.frame= view.bounds;

    //  创建渐变色数组，需要转换为CGColor颜色

    gradientLayer.colors=@[(__bridgeid)[UIColorcolorWithHexString:fromHexColorStr].CGColor,(__bridgeid)[UIColorcolorWithHexString:toHexColorStr].CGColor];

    //  设置渐变颜色方向，左上点为(0,0), 右下点为(1,1)

    gradientLayer.startPoint=CGPointMake(0,0);

    gradientLayer.endPoint=CGPointMake(1,1);

    //  设置颜色变化点，取值范围 0.0~1.0

    gradientLayer.locations=@[@0,@1];

    UIGraphicsBeginImageContextWithOptions(gradientLayer.frame.size, NO, 0);

    [gradientLayerrenderInContext:UIGraphicsGetCurrentContext()];

    UIImage *outputImage = UIGraphicsGetImageFromCurrentImageContext();

    UIGraphicsEndImageContext();

    returnoutputImage;

}