iOS 畫餅圖

效果圖：

核心代碼：

#import "PieView.h"

@implementation PieView



- (void)drawRect:(CGRect)rect {
    // Drawing code

    NSArray *dataArray = @[@25,@25,@15,@15,@10,@10];
    CGPoint center =  CGPointMake(self.bounds.size.width * 0.5, self.bounds.size.height * 0.5);
    CGFloat radius = self.bounds.size.width * 0.5 - 10;
    CGFloat startA = 0;
    CGFloat angle = 0;
    CGFloat endA = 0;

    for (NSNumber *num in dataArray) {

        startA = endA;
        angle = num.intValue / 100.0 * M_PI * 2;
        endA = startA + angle;
        UIBezierPath  *path = [UIBezierPath bezierPathWithArcCenter:center radius:radius startAngle:startA endAngle:endA clockwise:YES];
        [[self randomColor] set];
        //添加一根線到圓心
        [path addLineToPoint:center];
        [path fill];
    }

}


-(void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{

    //重繪
    [self setNeedsDisplay];
}


//生成一個隨機的顏色
- (UIColor *)randomColor {

    CGFloat r = arc4random_uniform(256) / 255.0;
    CGFloat g = arc4random_uniform(256) / 255.0;
    CGFloat b = arc4random_uniform(256) / 255.0;

   return  [UIColor colorWithRed:r green:g blue:b alpha:1];
}




//一個一個的畫
- (void)drawPie{
    //畫第一個扇形
    CGPoint center =  CGPointMake(self.bounds.size.width * 0.5, self.bounds.size.height * 0.5);
    CGFloat radius = self.bounds.size.width * 0.5 - 10;
    CGFloat startA = 0;
    CGFloat angle = 25 / 100.0 * M_PI * 2;
    CGFloat endA = startA + angle;

    UIBezierPath *path = [UIBezierPath bezierPathWithArcCenter:center radius:radius startAngle:startA endAngle:endA clockwise:YES];

    [[UIColor redColor] set];
    //添加一根線到圓心
    [path addLineToPoint:center];
    [path fill];

    //畫第二個扇形

    startA = endA;
    angle = 25 / 100.0 * M_PI * 2;
    endA = startA + angle;
    path = [UIBezierPath bezierPathWithArcCenter:center radius:radius startAngle:startA endAngle:endA clockwise:YES];
    [[UIColor greenColor] set];
    //添加一根線到圓心
    [path addLineToPoint:center];
    [path fill];


    startA = endA;
    angle = 50 / 100.0 * M_PI * 2;
    endA = startA + angle;
    path = [UIBezierPath bezierPathWithArcCenter:center radius:radius startAngle:startA endAngle:endA clockwise:YES];
    [[UIColor blueColor] set];
    //添加一根線到圓心
    [path addLineToPoint:center];
    [path fill];

}


@end