//此方法目前只能添加在self視圖上（如果有視圖在self視圖上，可能會遮蓋線條），畫的是虛線
//調用
[self drawRect:self.frame];
//覆寫
- (void)drawRect:(CGRect)rect
{
    CGContextRef context = UIGraphicsGetCurrentContext();
    CGContextBeginPath(context);
    CGContextSetLineWidth(context, 1 *kScreenScale);//線條長度
    CGContextSetStrokeColorWithColor(context, [UIColor colorWithHex:@"#959595"].CGColor);//線條顏色
    CGFloat lengths[] = {2*kScreenScale,1*kScreenScale};//設置虛線
    CGContextSetLineDash(context, 0, lengths, 2);//設置虛線
    CGContextMoveToPoint(context, 5 *kScreenScale, 3*kScreenScale);//起點
    CGContextAddLineToPoint(context, 360*kScreenScale, 3*kScreenScale);//畫到第一個點
    CGContextAddLineToPoint(context, 362*kScreenScale, 5*kScreenScale);//畫到第二個點
    CGContextAddLineToPoint(context, 362*kScreenScale, 100*kScreenScale);//以下類推
    CGContextAddLineToPoint(context, 360*kScreenScale, 101*kScreenScale);
    CGContextAddLineToPoint(context, 5*kScreenScale, 101*kScreenScale);
    CGContextAddLineToPoint(context, 4*kScreenScale, 100*kScreenScale);
    CGContextAddLineToPoint(context, 4*kScreenScale, 5*kScreenScale);
    CGContextAddLineToPoint(context, 5 *kScreenScale, 3*kScreenScale);
    CGContextStrokePath(context);//收尾
    CGContextClosePath(context);//結束
}