iOS开发之虚线动画

实现虚线动画
效果就是下面这张图循环动起来:

实现:

/**
 * lineView:       需要绘制成虚线的view
 * lineLength:     虚线的宽度
 * lineSpacing:    虚线的间距
 * lineColor:      虚线的颜色
 **/
- (void)drawDashLine:(UIView *)lineView lineLength:(int)lineLength lineSpacing:(int)lineSpacing lineColor:(UIColor *)lineColor
{
    //  设置路径
    UIBezierPath *path      = [UIBezierPath bezierPathWithRect:lineView.bounds];

    CAShapeLayer *shapeLayer = [CAShapeLayer layer];
    [shapeLayer setBounds:lineView.bounds];
    [shapeLayer setFillColor:[UIColor clearColor].CGColor];
    //  设置虚线颜色为blackColor
    [shapeLayer setStrokeColor:lineColor.CGColor];
    //  设置虚线宽度
    [shapeLayer setLineWidth:3.f];
    // 设置线条圆角
    [shapeLayer setLineCap:kCALineJoinRound];
    //  设置线宽，线间距
    [shapeLayer setLineDashPattern:[NSArray arrayWithObjects:@(lineLength),@(lineSpacing), nil]];
    //设置路径
    [shapeLayer setPath:path.CGPath];
    [lineView.layer addSublayer:shapeLayer];
    //加动画
    CABasicAnimation *dashAnimation = [CABasicAnimation
                                       animationWithKeyPath:@"lineDashPhase"];
    [dashAnimation setFromValue:[NSNumber numberWithFloat:0.0f]];
    [dashAnimation setToValue:[NSNumber numberWithFloat:300.f]];
    [dashAnimation setDuration:4.f];
    dashAnimation.cumulative = YES; //关键属性，自己看文档
    [dashAnimation setRepeatCount:MAXFLOAT];
    dashAnimation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionLinear];
    [shapeLayer addAnimation:dashAnimation forKey:@"linePhase"];
}

加载实现:

    UIView *lineView = [[UIView alloc] initWithFrame:CGRectMake(self.view.center.x, self.view.center.y, 100,100)];
    [self.view addSubview:lineView];
    [self drawDashLine:lineView lineLength:16 lineSpacing:15 lineColor:[UIColor redColor]];