自定义划线方法

#import "DrawLine.h"

@implementation DrawLine

+ (void)drawCenter:(UIImageView *)imageView withBeginX:(CGFloat)Bx withBeginY:(CGFloat)By withEndX:(CGFloat)Ex withEndY:(CGFloat)Ey withLineWidth:(CGFloat)width withColorR:(CGFloat)r
G:(CGFloat)g B:(CGFloat)b Alpha:(CGFloat)a
{

UIGraphicsBeginImageContext(imageView.frame.size);
[imageView.image drawInRect:CGRectMake(0,
0, imageView.frame.size.width, imageView.frame.size.height)];

CGContextSetLineCap(UIGraphicsGetCurrentContext(), kCGLineCapRound);
CGContextSetLineWidth(UIGraphicsGetCurrentContext(), width);
//线宽
CGContextSetAllowsAntialiasing(UIGraphicsGetCurrentContext(),
YES);
CGContextSetRGBStrokeColor(UIGraphicsGetCurrentContext(), r, g, b, a);
//颜色
CGContextBeginPath(UIGraphicsGetCurrentContext());
CGContextMoveToPoint(UIGraphicsGetCurrentContext(), Bx, By);
//起点坐标
CGContextAddLineToPoint(UIGraphicsGetCurrentContext(), Ex, Ey);
//终点坐标
CGContextStrokePath(UIGraphicsGetCurrentContext());
imageView.image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();

}

+ (void)drawLineCenter:(UIView *)view withBeginX:(CGFloat)Bx withBeginY:(CGFloat)By withEndX:(CGFloat)Ex withEndY:(CGFloat)Ey withLineWidth:(CGFloat)width withColorR:(CGFloat)r G:(CGFloat)g
B:(CGFloat)b Alpha:(CGFloat)a
{
UIImageView *imageView=[[UIImageView alloc] initWithFrame:view.frame];
imageView.frame = CGRectMake(view.frame.origin.x, view.frame.origin.y,
500, view.frame.size.height);

[view addSubview:imageView];
view.backgroundColor = [UIColor clearColor];

UIGraphicsBeginImageContext(imageView.frame.size);
[imageView.image drawInRect:CGRectMake(0,
0, imageView.frame.size.width, imageView.frame.size.height)];

CGContextSetLineCap(UIGraphicsGetCurrentContext(), kCGLineCapRound);
CGContextSetLineWidth(UIGraphicsGetCurrentContext(), width);
//线宽
CGContextSetAllowsAntialiasing(UIGraphicsGetCurrentContext(),
YES);
CGContextSetRGBStrokeColor(UIGraphicsGetCurrentContext(), r, g, b, a);
//颜色
CGContextBeginPath(UIGraphicsGetCurrentContext());
CGContextMoveToPoint(UIGraphicsGetCurrentContext(), Bx, By);
//起点坐标
CGContextAddLineToPoint(UIGraphicsGetCurrentContext(), Ex, Ey);
//终点坐标
CGContextStrokePath(UIGraphicsGetCurrentContext());
imageView.image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();

}