Quartz2D基础~饼状图

代码：

////  ZQDraw.m//  ////  Created by QiZhang on 11/26/15.////#import "ZQDraw.h"#import "UIColor+Random.h"#define kWidth 30#define kMargin kWidth@implementation ZQDraw- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{    [self setNeedsDisplay];}// Only override drawRect: if you perform custom drawing.// An empty implementation adversely affects performance during animation.- (void)drawRect:(CGRect)rect {    [self testZhu];}// 柱状图- (void)testZhu{    NSArray *data = @[@"50",@"50",@"100"];    // get context    CGContextRef ctx = UIGraphicsGetCurrentContext();    for (int i = 0; i < data.count ; i++) {        // 构建路径        UIBezierPath *path = [UIBezierPath bezierPathWithRect:CGRectMake(i * (kWidth + kMargin), 200 - [data[i] intValue], kWidth,[data[i] intValue])];        // 把路径添加到上下文        CGContextAddPath(ctx, path.CGPath);        [[UIColor randomColor] set];        CGContextFillPath(ctx);    }}// 饼状图- (void)testPie{    NSArray *data = @[@25,@25,@50];    CGContextRef ctx = UIGraphicsGetCurrentContext();    // 拼接路径    CGPoint center = CGPointMake(100, 100);    CGFloat radius = 100;    CGFloat startA = 0;    CGFloat endA = 0;    CGFloat angle = 0;    for (NSNumber *number in data) {        startA = endA;        angle = number.intValue / 100.0 * M_PI * 2;        endA = startA + angle;        UIBezierPath *path = [UIBezierPath bezierPathWithArcCenter:center radius:radius startAngle:startA endAngle:endA clockwise:YES];        [path addLineToPoint:center];        // 添加到上下文        [[UIColor randomColor] set];        CGContextAddPath(ctx, path.CGPath);        CGContextFillPath(ctx);    }}- (void)test{    // 得到上下文    CGContextRef ctx = UIGraphicsGetCurrentContext();    CGPoint center = CGPointMake(100, 100);    CGFloat radius = 100;    CGFloat startA = 0;    CGFloat endA = 0;    CGFloat angle = 0;    // 第一个扇形    angle = 25/100.0 * M_PI * 2;    endA = startA + angle;    UIBezierPath *path = [UIBezierPath bezierPathWithArcCenter:center radius:radius startAngle:startA endAngle:endA clockwise:YES];    [path addLineToPoint:center];    // 添加到上下文    CGContextAddPath(ctx, path.CGPath);    [[UIColor redColor] set];    // 渲染    CGContextFillPath(ctx);    // 第二个扇形    startA = endA;    angle = 25 / 100.0 * M_PI * 2;    endA = startA + angle;    UIBezierPath *path1 = [UIBezierPath bezierPathWithArcCenter:center radius:radius startAngle:startA endAngle:endA clockwise:YES];    [path1 addLineToPoint:center];    // 添加到上下文    CGContextAddPath(ctx, path1.CGPath);    [[UIColor greenColor] set];    // 渲染    CGContextFillPath(ctx);    // 第三个扇形    startA = endA;    angle = 50 / 100.0 * M_PI * 2;    endA = startA + angle;    UIBezierPath *path2 = [UIBezierPath bezierPathWithArcCenter:center radius:radius startAngle:startA endAngle:endA clockwise:YES];    [path2 addLineToPoint:center];    // 添加到上下文    CGContextAddPath(ctx, path2.CGPath);    [[UIColor blueColor] set];    // 渲染    CGContextFillPath(ctx);}@end

截图：