虚线的实现

转载：http://blog.csdn.net/zh198964/article/details/47727053

因为项目需要画虚线，起初想用图片重复叠加实现。搜罗了一圈还是封装一个UIView

代码如下

.h文件

[objc]view
 plain copy

#import <UIKit/UIKit.h>  

@interface DashesLineView : UIView  

@property(nonatomic)CGPoint startPoint;//虚线起点  

@property(nonatomic)CGPoint endPoint;//虚线终点  

@property(nonatomic,strong)UIColor* lineColor;//虚线颜色  

@end

.m文件

[objc]view
 plain copy

#import "DashesLineView.h"  

#define kInterval 10                                // 全局间距  

@implementation DashesLineView  

- (id)initWithFrame:(CGRect)frame  

{  

    self= [super initWithFrame:frame];  

    if(self) {  

        _lineColor = [UIColor redColor];  

        _startPoint = CGPointMake(0, 1);  

        _endPoint = CGPointMake(screen_width , 1);  

    }  

    return self;  

}  

- (void)drawRect:(CGRect)rect {  

    CGContextRef context = UIGraphicsGetCurrentContext();  

    CGContextBeginPath(context);  

    CGContextSetLineWidth(context,0.5);//线宽度  

    CGContextSetStrokeColorWithColor(context,self.lineColor.CGColor);  

    CGFloat lengths[] = {4,2};//先画4个点再画2个点  

    CGContextSetLineDash(context,0, lengths,2);//注意2(count)的值等于lengths数组的长度  

    CGContextMoveToPoint(context,self.startPoint.x,self.startPoint.y);  

    CGContextAddLineToPoint(context,self.endPoint.x,self.endPoint.y);  

    CGContextStrokePath(context);  

    CGContextClosePath(context);  

}  

@end