ios - 设置颜色渐变可以多颜色

/// label 动画
- (void)bilingbiling{
    CAGradientLayer *gradientLayer = [CAGradientLayer layer];
    gradientLayer.frame = CGRectMake(0, 0, self.itemLbBackView.width, self.itemLbBackView.height);
    
    gradientLayer.startPoint = CGPointMake(0.0, 1.0);
    gradientLayer.endPoint = CGPointMake(1.0, 1.0);
    gradientLayer.colors = @[
    (id)UIColorFromRGB(0xffffff).CGColor,
    (id)UIColor.redColor.CGColor,
    (id)UIColor.orangeColor.CGColor,
    (id)UIColor.blueColor.CGColor,
    (id)UIColor.greenColor.CGColor,
    (id)UIColorFromRGB(0xffffff).CGColor];

    gradientLayer.locations = @[@0,@0,@0,@0,@0,@0];
    self.gradientLayer = gradientLayer;
    
    [self.itemLbBackView.layer insertSublayer:gradientLayer atIndex:0];
    gradientLayer.mask = self.itemLb.layer;

}


/// 添加动画
- (void)addGradientanimation{
    self.isNeedShowAnimation = NO;
    
    CABasicAnimation * gradientanimation = [CABasicAnimation animationWithKeyPath:@"locations"];
    gradientanimation.removedOnCompletion = YES;
    gradientanimation.fromValue = @[@0, @0.1, @0.2, @0.3, @0.4,@0.5];
    gradientanimation.toValue = @[@0.5,@0.6 ,@0.7,@0.8,@0.9,@1];
    gradientanimation.duration = 1.5;
    gradientanimation.repeatCount = 1;
    gradientanimation.delegate = self;
    
    [self.gradientLayer addAnimation:gradientanimation forKey:@"gradientanimation"];
}