转载自http://blog.csdn.net/zhibudefeng/article/details/8463268/#

// Only override drawRect: if you perform custom drawing.

// An empty implementation adversely affects performance during animation.

- (void)drawRect:(CGRect)rect

{

CGContextRef context = UIGraphicsGetCurrentContext();

/*NO.1画一条线

CGContextSetRGBStrokeColor(context, 0.5, 0.5, 0.5, 0.5);//线条颜色

CGContextMoveToPoint(context, 20, 20);

CGContextAddLineToPoint(context, 200,20);

CGContextStrokePath(context);

*/

/*NO.2写文字

CGContextSetLineWidth(context, 1.0);

CGContextSetRGBFillColor (context, 0.5, 0.5, 0.5, 0.5);

UIFont  *font = [UIFont boldSystemFontOfSize:18.0];

[@"公司：北京中软科技股份有限公司\n部门：ERP事业部\n姓名：McLiang" drawInRect:CGRectMake(20, 40, 280, 300) withFont:font];

*/

/*NO.3画一个正方形图形 没有边框

CGContextSetRGBFillColor(context, 0, 0.25, 0, 0.5);

CGContextFillRect(context, CGRectMake(2, 2, 270, 270));

CGContextStrokePath(context);

*/

/*NO.4画正方形边框

CGContextSetRGBStrokeColor(context, 0.5, 0.5, 0.5, 0.5);//线条颜色

CGContextSetLineWidth(context, 2.0);

CGContextAddRect(context, CGRectMake(2, 2, 270, 270));

CGContextStrokePath(context);

*/

/*NO.5画方形背景颜色

CGContextTranslateCTM(context, 0.0f, self.bounds.size.height);

CGContextScaleCTM(context, 1.0f, -1.0f);

UIGraphicsPushContext(context);

CGContextSetLineWidth(context,320);

CGContextSetRGBStrokeColor(context, 250.0/255, 250.0/255, 210.0/255, 1.0);

CGContextStrokeRect(context, CGRectMake(0, 0, 320, 460));

UIGraphicsPopContext();

*/

/*NO.6椭圆

CGRect aRect= CGRectMake(80, 80, 160, 100);

CGContextSetRGBStrokeColor(context, 0.6, 0.9, 0, 1.0);

CGContextSetLineWidth(context, 3.0);

CGContextAddEllipseInRect(context, aRect); //椭圆

CGContextDrawPath(context, kCGPathStroke);

*/

/*NO.7

CGContextBeginPath(context);

CGContextSetRGBStrokeColor(context, 0, 0, 1, 1);

CGContextMoveToPoint(context, 100, 100);

CGContextAddArcToPoint(context, 50, 100, 50, 150, 50);

CGContextStrokePath(context);

*/

/*NO.8渐变

CGContextClip(context);

CGColorSpaceRef rgb = CGColorSpaceCreateDeviceRGB();

CGFloat colors[] =

{

204.0 / 255.0, 224.0 / 255.0, 244.0 / 255.0, 1.00,

29.0 / 255.0, 156.0 / 255.0, 215.0 / 255.0, 1.00,

0.0 / 255.0,  50.0 / 255.0, 126.0 / 255.0, 1.00,

};

CGGradientRef gradient = CGGradientCreateWithColorComponents

(rgb, colors, NULL, sizeof(colors)/(sizeof(colors[0])*4));

CGColorSpaceRelease(rgb);

CGContextDrawLinearGradient(context, gradient,CGPointMake

(0.0,0.0) ,CGPointMake(0.0,self.frame.size.height),

kCGGradientDrawsBeforeStartLocation);

*/

/* NO.9四条线画一个正方形

//画线

UIColor *aColor = [UIColor colorWithRed:0 green:1.0 blue:0 alpha:0];

CGContextSetRGBStrokeColor(context, 1.0, 0, 0, 1.0);

CGContextSetFillColorWithColor(context, aColor.CGColor);

CGContextSetLineWidth(context, 4.0);

CGPoint aPoints[5];

aPoints[0] =CGPointMake(60, 60);

aPoints[1] =CGPointMake(260, 60);

aPoints[2] =CGPointMake(260, 300);

aPoints[3] =CGPointMake(60, 300);

aPoints[4] =CGPointMake(60, 60);

CGContextAddLines(context, aPoints, 5);

CGContextDrawPath(context, kCGPathStroke); //开始画线

*/

/*  NO.10

UIColor *aColor = [UIColor colorWithRed:0 green:1.0 blue:0 alpha:0];

CGContextSetRGBStrokeColor(context, 1.0, 0, 0, 1.0);

CGContextSetFillColorWithColor(context, aColor.CGColor);

//椭圆

CGRect aRect= CGRectMake(80, 80, 160, 100);

CGContextSetRGBStrokeColor(context, 0.6, 0.9, 0, 1.0);

CGContextSetLineWidth(context, 3.0);

CGContextSetFillColorWithColor(context, aColor.CGColor);

CGContextAddRect(context, rect); //矩形

CGContextAddEllipseInRect(context, aRect); //椭圆

CGContextDrawPath(context, kCGPathStroke);

*/

/*  NO.11

画一个实心的圆

CGContextFillEllipseInRect(context, CGRectMake(95, 95, 100.0, 100));

*/

/*NO.12

画一个菱形

CGContextSetLineWidth(context, 2.0);

CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor);

CGContextMoveToPoint(context, 100, 100);

CGContextAddLineToPoint(context, 150, 150);

CGContextAddLineToPoint(context, 100, 200);

CGContextAddLineToPoint(context, 50, 150);

CGContextAddLineToPoint(context, 100, 100);

CGContextStrokePath(context);

*/

/*NO.13 画矩形

CGContextSetLineWidth(context, 2.0);

CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor);

CGRect rectangle = CGRectMake(60,170,200,80);

CGContextAddRect(context, rectangle);

CGContextStrokePath(context);

*/

/*椭圆

CGContextSetLineWidth(context, 2.0);

CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor);

CGRect rectangle = CGRectMake(60,170,200,80);

CGContextAddEllipseInRect(context, rectangle);

CGContextStrokePath(context);

*/

/*用红色填充了一段路径:

CGContextMoveToPoint(context, 100, 100);

CGContextAddLineToPoint(context, 150, 150);

CGContextAddLineToPoint(context, 100, 200);

CGContextAddLineToPoint(context, 50, 150);

CGContextAddLineToPoint(context, 100, 100);

CGContextSetFillColorWithColor(context, [UIColor redColor].CGColor);

CGContextFillPath(context);

*/

/*填充一个蓝色边的红色矩形

CGContextSetLineWidth(context, 2.0);

CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor);

CGRect rectangle = CGRectMake(60,170,200,80);

CGContextAddRect(context, rectangle);

CGContextStrokePath(context);

CGContextSetFillColorWithColor(context, [UIColor redColor].CGColor);

CGContextFillRect(context, rectangle);

*/

/*画弧

//弧线的是通过指定两个切点，还有角度，调用CGContextAddArcToPoint()绘制

CGContextSetLineWidth(context, 2.0);

CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor);

CGContextMoveToPoint(context, 100, 100);

CGContextAddArcToPoint(context, 100,200, 300,200, 100);

CGContextStrokePath(context);

*/

/*

绘制贝兹曲线

//贝兹曲线是通过移动一个起始点，然后通过两个控制点,还有一个中止点，调用CGContextAddCurveToPoint() 函数绘制

CGContextSetLineWidth(context, 2.0);

CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor);

CGContextMoveToPoint(context, 10, 10);

CGContextAddCurveToPoint(context, 0, 50, 300, 250, 300, 400);

CGContextStrokePath(context);

*/

/*绘制二次贝兹曲线

CGContextSetLineWidth(context, 2.0);

CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor);

CGContextMoveToPoint(context, 10, 200);

CGContextAddQuadCurveToPoint(context, 150, 10, 300, 200);

CGContextStrokePath(context);

*/

/*绘制虚线

CGContextSetLineWidth(context, 5.0);

CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor);

CGFloat dashArray[] = {2,6,4,2};

CGContextSetLineDash(context, 3, dashArray, 4);//跳过3个再画虚线，所以刚开始有6-（3-2）=5个虚点

CGContextMoveToPoint(context, 10, 200);

CGContextAddQuadCurveToPoint(context, 150, 10, 300, 200);

CGContextStrokePath(context);

*/

/*绘制图片

NSString* imagePath = [[NSBundle mainBundle] pathForResource:@"dog" ofType:@"png"];

UIImage* myImageObj = [[UIImage alloc] initWithContentsOfFile:imagePath];

//[myImageObj drawAtPoint:CGPointMake(0, 0)];

[myImageObj drawInRect:CGRectMake(0, 0, 320, 480)];

NSString *s = @"我的小狗";

[s drawAtPoint:CGPointMake(100, 0) withFont:[UIFont systemFontOfSize:34.0]];

*/

/*

NSString *path = [[NSBundle mainBundle] pathForResource:@"dog" ofType:@"png"];

UIImage *img = [UIImage imageWithContentsOfFile:path];

CGImageRef image = img.CGImage;

CGContextSaveGState(context);

CGRect touchRect = CGRectMake(0, 0, img.size.width, img.size.height);

CGContextDrawImage(context, touchRect, image);

CGContextRestoreGState(context);

*/

/*NSString *path = [[NSBundle mainBundle] pathForResource:@"dog" ofType:@"png"];

UIImage *img = [UIImage imageWithContentsOfFile:path];

CGImageRef image = img.CGImage;

CGContextSaveGState(context);

CGContextRotateCTM(context, M_PI);

CGContextTranslateCTM(context, -img.size.width, -img.size.height);

CGRect touchRect = CGRectMake(0, 0, img.size.width, img.size.height);

CGContextDrawImage(context, touchRect, image);

CGContextRestoreGState(context);*/

/*

NSString *path = [[NSBundle mainBundle] pathForResource:@"dog" ofType:@"png"];

UIImage *img = [UIImage imageWithContentsOfFile:path];

CGImageRef image = img.CGImage;

CGContextSaveGState(context);

CGAffineTransform myAffine = CGAffineTransformMakeRotation(M_PI);

myAffine = CGAffineTransformTranslate(myAffine, -img.size.width, -img.size.height);

CGContextConcatCTM(context, myAffine);

CGContextRotateCTM(context, M_PI);

CGContextTranslateCTM(context, -img.size.width, -img.size.height);

CGRect touchRect = CGRectMake(0, 0, img.size.width, img.size.height);

CGContextDrawImage(context, touchRect, image);

CGContextRestoreGState(context);

*/

}