//CAShapeLayer是通过给一条曲线来绘制的，我们可以给定不同曲线来制造动画，我们也可以改变下面的曲线来制造动画//  self.backgroundLayer.strokeStart=0.0f;//  self.backgroundLayer.strokeEnd=1.0f;

[self.backgroundLayer setLineJoin:@"round"];//设置线条的相交模式        [self.backgroundLayer setLineDashPattern:@[@(50.0),@(2.0)]];//设置线条的间隔50来填充，2个单元来空格，就是创造虚线

//CAShapeLayer还可以用于遮罩层，就是全部遮罩起来，只显示路线框起来的部分／／看着，这个layer的frame启示只要装的下路径就可以了，不用遮罩整个屏幕
用于这种情况的下的路径，只能通过CGPathCreateMutable来绘制路线，否则没效果，不能采用uikit或者cgcontextref这些来绘制
 UIImage *image=[UIImage imageNamed:@"scratch_46.jpg"];    [[[self view]layer] setContents:(id)[image CGImage]];    CGMutablePathRef path =CGPathCreateMutable();    CGPathMoveToPoint(path, NULL, 0, 100);    CGPathAddLineToPoint(path,NULL, 200, 0);    CGPathAddLineToPoint(path, NULL, 200, 200);    CGPathAddLineToPoint(path, NULL, 0, 100);    CAShapeLayer *masklayer=  [CAShapeLayer layer];    [masklayer setBounds:CGRectMake(0, 0, 200, 200)];    [masklayer setPosition:CGPointMake(200, 200)];    [masklayer setPath:path];    [[[self view] layer]setMask:masklayer];

#import "RecordingCircleOverlayView.h"@implementation RecordingCircleOverlayView-(id)init{    self=[super init];    if (self) {        }    return self;}-(id)initWithFrame:(CGRect) frame{    self=[super initWithFrame:frame];    if (self) {        self.progressLayers=[NSMutableArray array];        CGPoint arcCenter = CGPointMake(CGRectGetMidY(self.bounds), CGRectGetMidX(self.bounds));        CGFloat radius = CGRectGetMidX(self.bounds);        self.beipath = [UIBezierPath bezierPathWithArcCenter:arcCenter                                                      radius:radius                                                  startAngle:M_PI                                                    endAngle:-M_PI                                                   clockwise:NO];        self.backgroundLayer=[CAShapeLayer layer];        self.backgroundLayer.frame=self.bounds;        self.backgroundLayer.path=self.beipath.CGPath;        self.backgroundLayer.strokeColor=[[UIColor lightGrayColor] CGColor];        self.backgroundLayer.fillColor = [[UIColor clearColor] CGColor];        self.backgroundLayer.lineWidth = 2.0;        self.backgroundLayer.strokeStart=0.0f;        self.backgroundLayer.strokeEnd=1.0f;                [self.layer addSublayer:self.backgroundLayer];        UITapGestureRecognizer *tap=   [[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(updateAnimations)];        [self addGestureRecognizer:tap];        [self addNewLayer];    }    return self;}- (void)addNewLayer{    CAShapeLayer *progressLayer = [CAShapeLayer layer];    progressLayer.path = self.beipath.CGPath;    progressLayer.strokeColor = [UIColor colorWithRed:(CGFloat)rand()/(CGFloat)RAND_MAX green:(CGFloat)rand()/(CGFloat)RAND_MAX blue:(CGFloat)rand()/(CGFloat)RAND_MAX alpha:1.0].CGColor;    progressLayer.fillColor = [[UIColor clearColor] CGColor];    progressLayer.lineWidth = 2.0;    progressLayer.strokeEnd = 0.1f;//将这条被塞尔曲线划分成10分，这里只绘制0.1，其他的同理,那么就可以添加动画了        [self.layer addSublayer:progressLayer];    [self.progressLayers addObject:progressLayer];        self.currentProgressLayer = progressLayer;}#pragma mark 添加动画- (void)updateAnimations{    CGFloat duration = self.duration * (1.f - [[self.progressLayers firstObject] strokeEnd]);    CGFloat strokeEndFinal = 1.f;        for (CAShapeLayer *progressLayer in self.progressLayers)    {        CABasicAnimation *strokeEndAnimation = nil;        strokeEndAnimation = [CABasicAnimation animationWithKeyPath:@"strokeEnd"];        strokeEndAnimation.duration = duration;        strokeEndAnimation.fromValue = @(progressLayer.strokeEnd);        strokeEndAnimation.toValue = @(strokeEndFinal);        strokeEndAnimation.autoreverses = NO;        strokeEndAnimation.repeatCount = 0.f;        strokeEndAnimation.fillMode = kCAFillModeForwards;        strokeEndAnimation.removedOnCompletion = NO;        strokeEndAnimation.delegate = self;        [progressLayer addAnimation:strokeEndAnimation forKey:@"strokeEndAnimation"];                strokeEndFinal -= (progressLayer.strokeEnd - progressLayer.strokeStart);                if (progressLayer != self.currentProgressLayer)        {            CABasicAnimation *strokeStartAnimation = nil;            strokeStartAnimation = [CABasicAnimation animationWithKeyPath:@"strokeStart"];            strokeStartAnimation.duration = duration;            strokeStartAnimation.fromValue = @(progressLayer.strokeStart);            strokeStartAnimation.toValue = @(strokeEndFinal);            strokeStartAnimation.autoreverses = NO;            strokeStartAnimation.repeatCount = 0.f;            strokeStartAnimation.fillMode = kCAFillModeForwards;            strokeStartAnimation.removedOnCompletion = NO;            [progressLayer addAnimation:strokeStartAnimation forKey:@"strokeStartAnimation"];        }    }    CABasicAnimation *backgroundLayerAnimation = [CABasicAnimation animationWithKeyPath:@"strokeStart"];    backgroundLayerAnimation.duration = duration;    backgroundLayerAnimation.fromValue = @(self.backgroundLayer.strokeStart);    backgroundLayerAnimation.toValue = @(1.f);    backgroundLayerAnimation.autoreverses = NO;    backgroundLayerAnimation.repeatCount = 0.f;    backgroundLayerAnimation.fillMode = kCAFillModeForwards;    backgroundLayerAnimation.removedOnCompletion = NO;    backgroundLayerAnimation.delegate = self;    [self.backgroundLayer addAnimation:backgroundLayerAnimation forKey:@"strokeStartAnimation"];}@end

//CAGradientLayer常用于给定一个颜色数组，这个layer就能将这个颜色数组展示出来，动画一般就是修改其中的几个属性

#import "YHCAGradientLayer.h"@implementation YHCAGradientLayer-(id)initWithFrame:(CGRect)frame{  self=  [super initWithFrame:frame];    if (self) {        CAGradientLayer *layer = (id)[self layer];        [layer setStartPoint:CGPointMake(0.0, 0.0)];//满足ios坐标系        [layer setEndPoint:CGPointMake(1.0, 0.0)];//同理，开始点与结束点的连线，然后数组颜色来填充                        NSMutableArray *colors = [NSMutableArray array];        for (NSInteger hue = 0; hue <= 360; hue += 1) {            UIColor *color;            color = [UIColor colorWithHue:1.0 * hue / 360.0                               saturation:1.0                               brightness:1.0                                    alpha:1.0];            [colors addObject:(id)[color CGColor]];        }         [layer setColors:[NSArray arrayWithArray:colors]];        [self performAnimation];    }    return self;}#pragma  mark 为了简便，直接将原来的基层layer换成CAGradientLayer+(Class)layerClass{    return [CAGradientLayer class];}#pragma mark 动画- (void)performAnimation {    CAGradientLayer *layer = (id)[self layer];    NSMutableArray *mutable = [[layer colors] mutableCopy];    id lastColor = [mutable lastObject] ;    [mutable removeLastObject];    [mutable insertObject:lastColor atIndex:0];    NSArray *shiftedColors = [NSArray arrayWithArray:mutable];     [layer setColors:shiftedColors];        CABasicAnimation *animation;    animation = [CABasicAnimation animationWithKeyPath:@"colors"];    animation.toValue=shiftedColors;    [animation setDuration:0.008];    [animation setRemovedOnCompletion:YES];    [animation setFillMode:kCAFillModeForwards];    [animation setDelegate:self];    [layer addAnimation:animation forKey:@"animateGradient"];}#pragma mark 结束后再次调用，相当于永动了- (void)animationDidStop:(CAAnimation *)animation finished:(BOOL)flag {    [self performAnimation];}@end

- (void)viewDidLoad{    [super viewDidLoad];    CAGradientLayer *colorLayer = [CAGradientLayer layer];    colorLayer.frame    = (CGRect){CGPointZero, CGSizeMake(200, 200)};    colorLayer.position = self.view.center;    [self.view.layer addSublayer:colorLayer];    // 颜色分配    colorLayer.colors = @[(__bridge id)[UIColor redColor].CGColor,                          (__bridge id)[UIColor greenColor].CGColor,                          (__bridge id)[UIColor blueColor].CGColor];        // 颜色分割线    colorLayer.locations  = @[@(0.25), @(0.5), @(0.75)];        // 起始点    colorLayer.startPoint = CGPointMake(0, 0);        // 结束点    colorLayer.endPoint   = CGPointMake(1, 0);}

////  RootViewController.m////  Copyright (c) 2014年 Y.X. All rights reserved.//#import "RootViewController.h"#import "YXGCD.h"@interface RootViewController ()@property (nonatomic, strong) GCDTimer  *timer;@end@implementation RootViewController- (void)viewDidLoad{    [super viewDidLoad];    CAGradientLayer *colorLayer = [CAGradientLayer layer];    colorLayer.backgroundColor = [UIColor blueColor].CGColor;    colorLayer.frame    = (CGRect){CGPointZero, CGSizeMake(200, 200)};    colorLayer.position = self.view.center;    [self.view.layer addSublayer:colorLayer];    // 颜色分配    colorLayer.colors = @[(__bridge id)[UIColor cyanColor].CGColor,                          (__bridge id)[UIColor orangeColor].CGColor,                          (__bridge id)[UIColor magentaColor].CGColor];        // 起始点    colorLayer.startPoint = CGPointMake(0, 0);        // 结束点    colorLayer.endPoint   = CGPointMake(1, 0);        _timer = [[GCDTimer alloc] initInQueue:[GCDQueue mainQueue]];    [_timer event:^{                static CGFloat test = - 0.1f;                if (test >= 1.1)        {            test = - 0.1f;            [CATransaction setDisableActions:YES];            colorLayer.locations  = @[@(test), @(test + 0.05), @(test + 0.1)];        }        else        {            [CATransaction setDisableActions:NO];            colorLayer.locations  = @[@(test), @(test + 0.05), @(test + 0.1)];        }                test += 0.1f;            } timeInterval:NSEC_PER_SEC];    [_timer start];}@end

    _timer = [[GCDTimer alloc] initInQueue:[GCDQueue mainQueue]];    [_timer event:^{                static CGFloat test = - 0.1f;                if (test >= 1.1)        {            test = - 0.1f;            [CATransaction setDisableActions:NO];            colorLayer.locations  = @[@(test), @(test + 0.01), @(test + 0.011)];        }        else        {            [CATransaction setDisableActions:NO];            colorLayer.locations  = @[@(test), @(test + 0.01), @(test + 0.011)];        }                test += 0.1f;            } timeInterval:NSEC_PER_SEC];    [_timer start];

////  RootViewController.m////  Copyright (c) 2014年 Y.X. All rights reserved.//#import "RootViewController.h"#import "YXGCD.h"@interface RootViewController ()@property (nonatomic, strong) GCDTimer  *timer;@end// 将常数转换为度数#define   DEGREES(degrees)  ((M_PI * (degrees))/ 180.f)@implementation RootViewController- (void)viewDidLoad{    [super viewDidLoad];    self.view.backgroundColor = [UIColor blackColor];    CAGradientLayer *colorLayer = [CAGradientLayer layer];    colorLayer.backgroundColor = [UIColor blueColor].CGColor;    colorLayer.frame    = (CGRect){CGPointZero, CGSizeMake(200, 200)};    colorLayer.position = self.view.center;    [self.view.layer addSublayer:colorLayer];    // 颜色分配    colorLayer.colors = @[(__bridge id)[UIColor redColor].CGColor,                          (__bridge id)[UIColor whiteColor].CGColor,                          (__bridge id)[UIColor redColor].CGColor];    colorLayer.locations  = @[@(-0.2), @(-0.1), @(0)];        // 起始点    colorLayer.startPoint = CGPointMake(0, 0);        // 结束点    colorLayer.endPoint   = CGPointMake(1, 0);        CAShapeLayer *circle = [RootViewController LayerWithCircleCenter:CGPointMake(102, 100)                                                              radius:80                                                          startAngle:DEGREES(0)                                                            endAngle:DEGREES(360)                                                           clockwise:YES                                                     lineDashPattern:nil];    circle.strokeColor = [UIColor redColor].CGColor;    [self.view.layer addSublayer:circle];    circle.strokeEnd = 1.f;    colorLayer.mask = circle;        _timer = [[GCDTimer alloc] initInQueue:[GCDQueue mainQueue]];    [_timer event:^{        static int i = 0;        if (i++ % 2 == 0)        {            CABasicAnimation* fadeAnim = [CABasicAnimation animationWithKeyPath:@"locations"];            fadeAnim.fromValue = http://www.mamicode.com/@[@(-0.2), @(-0.1), @(0)];>