#import <QuartzCore/CALayer.h>

#import <Foundation/NSArray.h>

NS_ASSUME_NONNULL_BEGIN

CA_CLASS_AVAILABLE (10.6, 3.0, 9.0, 2.0)

@interface CAGradientLayer : CALayer

//颜色数组 CGColor

@property(nullable, copy) NSArray *colors;

//颜色区间范围数组，范围是[0-1]并且是递增

@property(nullable, copy) NSArray<NSNumber *> *locations;

//开始坐标和结束坐标 范围（0-1）

//默认值（0.5，0.0） （0.5，1.0）

@property CGPoint startPoint;

@property CGPoint endPoint;

//绘制类型，目前只有一个参数也是默认值kCAGradientLayerAxial

@property(copy) NSString *type;

@end

/** `type' values. **/

CA_EXTERN NSString * const kCAGradientLayerAxial

CA_AVAILABLE_STARTING (10.6, 3.0, 9.0, 2.0);

NS_ASSUME_NONNULL_END

    self.showView = [[UIView alloc] initWithFrame:CGRectMake(,(CScreenHeight-)/,CScreenWidth-,)];

    CAGradientLayer *layer = [CAGradientLayer layer];

    layer.frame = CGRectMake(,,CScreenWidth-,);

    layer.colors = @[(id)UIColor.redColor.CGColor,

                     (id)UIColor.whiteColor.CGColor,

                     (id)UIColor.redColor.CGColor];

    layer.locations = @[@(-0.2),@(-0.1),@];

    layer.startPoint = CGPointMake(, );

    layer.endPoint = CGPointMake(, );

    layer.type = kCAGradientLayerAxial;

    [self.showView.layer addSublayer:layer];

    self.layer = layer;

    self.showView.backgroundColor = [UIColor whiteColor];

    [self.view addSubview:self.showView];

    self.waterTimer = [NSTimer scheduledTimerWithTimeInterval: target:self selector:@selector(waterAction) userInfo:nil repeats:YES];

- (void)waterAction{

    CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:@"locations"];

    animation.fromValue = @[@(-0.3), @(-0.2), @()];

    animation.toValue   = @[@(1.0), @(1.2), @(1.3)];

    animation.duration  = ;

    [self.layer addAnimation:animation forKey:nil];

}