iOS UIBezierPath實現餅狀圖

#import <UIKit/UIKit.h>
 
NS_ASSUME_NONNULL_BEGIN
 
@interface CircleView : UIView
 
@property (nonatomic, copy) NSArray<NSNumber *> *valueArray;
 
@end
 
NS_ASSUME_NONNULL_END
 
 
//
 
 
#define S_W self.frame.size.width
 
#import "CircleView.h"
 
@interface CircleView ()
 
@property (nonatomic, copy) NSArray<NSNumber *> *dataArray;
@property (nonatomic, assign) CGFloat endAngleFloat; // 每個扇形起點角度
 
@end
 
@implementation CircleView
 
- (void)setValueArray:(NSArray<NSNumber *> *)valueArray {
 self.dataArray = valueArray;
 self.endAngleFloat = 0;
 [self creatUI];
}
 
- (void)creatUI {
 for (NSInteger i = 0; i<_dataArray.count; i++) {
 CAShapeLayer *shapeLayer = [CAShapeLayer layer];
 shapeLayer.lineWidth = 1;
 shapeLayer.fillColor = [UIColor colorWithRed:arc4random()%256/255.0f green:arc4random()%256/255.0f blue:arc4random()%256/255.0f alpha:1].CGColor;
 shapeLayer.strokeColor = shapeLayer.fillColor;
 
 CGFloat valueFloat = [_dataArray[i] floatValue];
 CGFloat angleFloat = valueFloat*2*M_PI/100;
 
 UIBezierPath *bezierPath = [UIBezierPath bezierPath];
 [bezierPath moveToPoint:CGPointMake(S_W/2, S_W/2)];
 [bezierPath addLineToPoint:CGPointMake(S_W*(1+cos(_endAngleFloat))/2, S_W*(1+sin(_endAngleFloat))/2)];
 [bezierPath addArcWithCenter:CGPointMake(S_W/2, S_W/2) radius:S_W/2 startAngle:_endAngleFloat endAngle:angleFloat+_endAngleFloat clockwise:YES];
 [bezierPath closePath];
 shapeLayer.path = bezierPath.CGPath;
 [self.layer addSublayer:shapeLayer];
 
 [self addLabelWithFloat:valueFloat angleFloat:angleFloat];
 
 _endAngleFloat += angleFloat;
 }
}
 
- (void)addLabelWithFloat:(CGFloat)valueFloat angleFloat:(CGFloat)angleFloat {
 UILabel *label = [[UILabel alloc] init];
 label.center = CGPointMake(S_W*(2+cos(angleFloat/2 + _endAngleFloat))/4, S_W*(2+sin(angleFloat/2 + _endAngleFloat))/4);
 label.bounds = CGRectMake(0, 0, 50, 50);
 label.text = [NSString stringWithFormat:@"%.f%%",valueFloat];
 label.textColor = UIColor.whiteColor;
 label.textAlignment = NSTextAlignmentCenter;
 label.font = [UIFont systemFontOfSize:14];
 [self addSubview:label];
}

CircleView *view = [[CircleView alloc] initWithFrame:CGRectMake(20, 100, self.view.frame.size.width-40, self.view.frame.size.width-40)];
 view.valueArray = @[@(10),@(20),@(30),@(40)];
 [self.view addSubview:view];