做项目让做一个加载动画,一个圈圈在转中间加一个图片,网上有好多demo,这里我也自己写了一个,中间的图片可加可不加。其中主要用到贝塞尔曲线。UIBezierPath是对CGContextRef的进一步封装,不多说直接上代码:
#import <UIKit/UIKit.h> @interface CircleLoader : UIView //进度颜色 @property(nonatomic, retain) UIColor* progressTintColor ; //轨道颜色 @property(nonatomic, retain) UIColor* trackTintColor ; //轨道宽度 @property (nonatomic,assign) float lineWidth; //中间图片 @property (nonatomic,strong) UIImage *centerImage; //进度 @property (nonatomic,assign) float progressValue; //提示标题 @property (nonatomic,strong) NSString *promptTitle; //开启动画 @property (nonatomic,assign) BOOL animationing; //隐藏消失 - (void)hide; @end
#import "CircleLoader.h" @interface CircleLoader () @property (nonatomic,strong) CAShapeLayer *trackLayer; @property (nonatomic,strong) CAShapeLayer *progressLayer; @end @implementation CircleLoader - (instancetype)initWithFrame:(CGRect)frame { self = [super initWithFrame:frame]; if (self) { self.backgroundColor=[UIColor clearColor]; } return self; } -(void)drawRect:(CGRect)rect { [super drawRect:rect]; _trackLayer=[CAShapeLayer layer]; _trackLayer.frame=CGRectMake(, , self.frame.size.width, self.frame.size.height); _trackLayer.lineWidth=_lineWidth; _trackLayer.strokeColor=_trackTintColor.CGColor; _trackLayer.fillColor = self.backgroundColor.CGColor; _trackLayer.lineCap = kCALineCapRound; [self.layer addSublayer:_trackLayer]; _progressLayer=[CAShapeLayer layer]; _progressLayer.frame=CGRectMake(, , self.frame.size.width, self.frame.size.height); _progressLayer.lineWidth=_lineWidth; _progressLayer.strokeColor=_progressTintColor.CGColor; _progressLayer.fillColor = self.backgroundColor.CGColor; _progressLayer.lineCap = kCALineCapRound; [self.layer addSublayer:_progressLayer]; if (_centerImage!=nil) { UIImageView *centerImgView=[[UIImageView alloc]initWithImage:_centerImage]; centerImgView.frame=CGRectMake(_lineWidth, _lineWidth, self.frame.size.width-*_lineWidth, self.frame.size.height-_lineWidth*); // centerImgView.center=self.center; centerImgView.layer.cornerRadius=(self.frame.size.width+_lineWidth)/; centerImgView.clipsToBounds=YES; [self.layer addSublayer:centerImgView.layer]; } [self start]; } - (void)drawBackgroundCircle:(BOOL) animationing { //贝塞尔曲线 0度是在十字右边方向 -M_PI/2相当于在十字上边方向 CGFloat startAngle = - ((); // 90 Degrees // CGFloat endAngle = ( * ();; CGPoint center = CGPointMake(self.bounds.size.width/, self.bounds.size.height/); CGFloat radius = (self.bounds.size.width - _lineWidth)/; UIBezierPath *processPath = [UIBezierPath bezierPath]; // processPath.lineWidth=_lineWidth; UIBezierPath *trackPath = [UIBezierPath bezierPath]; // trackPath.lineWidth=_lineWidth; //--------------------------------------- // Make end angle to 90% of the progress //--------------------------------------- if (!animationing) { endAngle = (_progressValue * *(float)M_PI) + startAngle; } else { endAngle = (*(float)M_PI) + startAngle; } [processPath addArcWithCenter:center radius:radius startAngle:startAngle endAngle:endAngle clockwise:YES]; [trackPath addArcWithCenter:center radius:radius startAngle: endAngle:*M_PI clockwise:YES]; _progressLayer.path = processPath.CGPath; _trackLayer.path=trackPath.CGPath; } - (void)start { [self drawBackgroundCircle:_animationing]; if (_animationing) { CABasicAnimation *rotationAnimation = [CABasicAnimation animationWithKeyPath:@"transform.rotation.z"]; rotationAnimation.toValue = [NSNumber numberWithFloat:M_PI * 2.0]; rotationAnimation.duration = ; rotationAnimation.cumulative = YES; rotationAnimation.repeatCount = HUGE_VALF; [_progressLayer addAnimation:rotationAnimation forKey:@"rotationAnimation"]; } } - (void)hide { [_progressLayer removeAllAnimations]; [self removeFromSuperview]; } @end
调用:
#import "ViewController.h" #import "CircleLoader.h" @interface ViewController () @end @implementation ViewController - (void)viewDidLoad { [super viewDidLoad]; // Do any additional setup after loading the view, typically from a nib. //设置视图大小 CircleLoader *view=[[CircleLoader alloc]initWithFrame:CGRectMake(, , , )]; //设置轨道颜色 view.trackTintColor=[UIColor redColor]; //设置进度条颜色 view.progressTintColor=[UIColor greenColor]; //设置轨道宽度 view.lineWidth=5.0; //设置进度 view.progressValue=0.7; //设置是否转到 YES进度不用设置 view.animationing=YES; //添加中间图片 不设置则不显示 view.centerImage=[UIImage imageNamed:@"yzp_loading"]; //添加视图 [self.view addSubview:view]; dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)( * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{ //视图隐藏 // [view hide]; }); } - (void)didReceiveMemoryWarning { [super didReceiveMemoryWarning]; // Dispose of any resources that can be recreated. } @end
效果: