标签:layer 屏幕 宽度 view send ack back poi black
使用CAShapeLayer 和 UIBezierPath 实现的画画功能。
1、首先根据触摸屏幕获取点信息:
- (CGPoint)pointWithTouches:(NSSet *)touches
{
UITouch *touch = [touches anyObject];
return [touch locationInView:self];
}
2、 重写响应方法:
- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event
- (void)touchesMoved:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event
- (void)touchesEnded:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event
3、绘制:
在- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event 中使用CAShapeLayer 和 UIBezierPath 绘制。
CAShapeLayer:
CAShapeLayer * slayer = [CAShapeLayer layer];
slayer.path = path.CGPath;
slayer.backgroundColor = [UIColor clearColor].CGColor;
slayer.fillColor = [UIColor clearColor].CGColor; //颜色
slayer.lineCap = kCALineCapRound;
slayer.lineJoin = kCALineJoinRound;
slayer.strokeColor = [UIColor blackColor].CGColor;
slayer.lineWidth = path.lineWidth; // 宽度
[self.layer addSublayer:slayer];
UIBezierPath:
UIBezierPath * path = [[UIBezierPath alloc] init];
path.lineWidth = width;
path.lineCapStyle = kCGLineCapRound; //线条拐角
path.lineJoinStyle = kCGLineCapRound; //终点处理
[path moveToPoint:startPoint];
标签:layer 屏幕 宽度 view send ack back poi black
原文地址:http://www.cnblogs.com/liuziyu/p/6513896.html