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//
//  AView.m
//  AutoLayout
//
//  Created by ZhuYi on 16/5/24.
//  Copyright © 2016年 ZY. All rights reserved.
//

#import "AView.h"

@implementation AView

// Only override drawRect: if you perform custom drawing.
// An empty implementation adversely affects performance during animation.

- (void)drawRect:(CGRect)rect {
    // Drawing code
    UIImage *image = [UIImage imageNamed:@"dropdown_anim__0005"];
    [image drawInRect:CGRectMake(, , rect.size.width, rect.size.height)];
//    [image drawAsPatternInRect:CGRectMake(0, 0, rect.size.width, rect.size.height)];

}

/**
 *      画三角形
 */
void drawTriangel(){
    //获得当前图形的上下文
    CGContextRef ctx = UIGraphicsGetCurrentContext();
    //设置七点
    CGContextMoveToPoint(ctx, , );
    CGContextAddLineToPoint(ctx, , );
    CGContextAddLineToPoint(ctx, , );
    //    CGContextAddLineToPoint(ctx, 0, 0);
    //关闭路径
    CGContextClosePath(ctx);
//    [[UIColor redColor] setFill];
//    [[UIColor redColor] set];
    CGContextSetRGBFillColor(ctx, , , , );
    CGContextFillPath(ctx);
}
/**
 *      画矩形
 */
void drawRect(){
    CGContextRef ctx = UIGraphicsGetCurrentContext();
    CGContextAddRect(ctx, CGRectMake(, , , ));
//    [[UIColor redColor] setStroke];
    CGContextSetRGBStrokeColor(ctx, , , , );
    CGContextStrokePath(ctx);
}

/**
 *      设置状态
 */
void set(){
    CGContextRef ctx = UIGraphicsGetCurrentContext();
    //设置开头和结尾的样式
    CGContextSetLineCap(ctx, kCGLineCapRound);
    //设置转折点的样式
    CGContextSetLineJoin(ctx, kCGLineJoinRound);

    CGContextMoveToPoint(ctx, , );
    CGContextAddLineToPoint(ctx, , );
    CGContextSetLineWidth(ctx, );
    CGContextSetRGBStrokeColor(ctx, , , , );
    CGContextStrokePath(ctx);

    CGContextMoveToPoint(ctx, , );
    CGContextAddLineToPoint(ctx, , );
    CGContextAddLineToPoint(ctx, , );
    CGContextSetRGBStrokeColor(ctx, , , , );
    CGContextSetLineWidth(ctx, );
    CGContextStrokePath(ctx);
}
/**
 *      画椭圆
 */
void ellipse(){
    CGContextRef ctx = UIGraphicsGetCurrentContext();
    CGContextSetRGBStrokeColor(ctx, , , , );
    CGContextSetLineWidth(ctx, );
    CGContextAddEllipseInRect(ctx, CGRectMake(, , , ));
    CGContextStrokePath(ctx);
}

/**
 *      画圆弧
 */
void arr(){
    CGContextRef ctx = UIGraphicsGetCurrentContext();
    CGContextAddArc(ctx, , , , , -M_PI_4, );
    CGContextSetLineWidth(ctx, );
    CGContextSetRGBStrokeColor(ctx, , , , );
    CGContextStrokePath(ctx);
}
/**
 *      画圆弧
 */
void cusarr(){
    CGContextRef ctx = UIGraphicsGetCurrentContext();
    CGContextMoveToPoint(ctx, , );
    CGContextAddLineToPoint(ctx, , );
    CGContextAddArc(ctx, , , , M_PI_2, M_PI, );
    CGContextClosePath(ctx);
    CGContextFillPath(ctx);
}

/**
 *  画文字
 */
void drawText()
{
    // 1.获得上下文
    CGContextRef ctx = UIGraphicsGetCurrentContext();
    // 2.画矩形
    CGRect cubeRect = CGRectMake(, , , );
    CGContextAddRect(ctx, cubeRect);
    // 3.显示所绘制的东西
    CGContextFillPath(ctx);

    // 4.画文字
    NSString *str = @"哈哈哈哈Good morning hello hi hi hi hi";
    //    [str drawAtPoint:CGPointZero withAttributes:nil];

    NSMutableDictionary *attrs = [NSMutableDictionary dictionary];
    // NSForegroundColorAttributeName : 文字颜色
    // NSFontAttributeName : 字体
    attrs[NSForegroundColorAttributeName] = [UIColor redColor];
    attrs[NSFontAttributeName] = [UIFont systemFontOfSize:];
    [str drawInRect:cubeRect withAttributes:attrs];
}
void drawImage()
{
    // 1.取得图片
    UIImage *image = [UIImage imageNamed:@"me"];

    // 2.画
    //    [image drawAtPoint:CGPointMake(50, 50)];
    //    [image drawInRect:CGRectMake(0, 0, 150, 150)];
    [image drawAsPatternInRect:CGRectMake(, , , )];

    // 3.画文字
//    NSString *str = @"为xxx所画";
//    [str drawInRect:CGRectMake(0, 180, 100, 30) withAttributes:nil];
}
/**
 *  矩阵操作和上下文栈
 */
void juzhencaozuo(){
    CGContextRef ctx = UIGraphicsGetCurrentContext();

    //保存上下文栈
    CGContextSaveGState(ctx);

    //矩阵操作
    CGContextRotateCTM(ctx, M_PI_4 * 0.3);
    CGContextScaleCTM(ctx, 0.5, 0.5);
    CGContextTranslateCTM(ctx, , );

    CGContextAddRect(ctx, CGRectMake(, , , ));

    CGContextStrokePath(ctx);

    //回复上下文栈
    CGContextRestoreGState(ctx);

    CGContextAddEllipseInRect(ctx, CGRectMake(, , , ));
    CGContextMoveToPoint(ctx, , );
    CGContextAddLineToPoint(ctx, , );

    // 矩阵操作
    //    CGContextScaleCTM(ctx, 0.5, 0.5);

    CGContextStrokePath(ctx);
}
/**
 *  裁剪
 */
void caijian(){
    CGContextRef ctx = UIGraphicsGetCurrentContext();

    CGContextSaveGState(ctx);

    // 0.画圆
    CGContextAddEllipseInRect(ctx, CGRectMake(, , , ));
    // 裁剪
    CGContextClip(ctx);
    CGContextFillPath(ctx);

    // 1.显示图片
    UIImage *image = [UIImage imageNamed:@"me"];
    [image drawAtPoint:CGPointMake(, )];
}
/**
 *  刷帧
 */
- (void)setRadios:(float)radios{
    _radios = radios;
    [self setNeedsDisplay];
}
- (void)shuazhen{
    ) {
        self.radios = ;
    }
    CGContextRef ctx = UIGraphicsGetCurrentContext();
    CGContextAddArc(ctx, , , self.radios, , M_PI * , );
    CGContextStrokePath(ctx);
}
@end

http://www.jianshu.com/p/734b34e82135