本文实例为大家分享了iOS实现转盘效果的具体代码，供大家参考，具体内容如下

Demo下载地址： iOS转盘效果

功能：实现了常用的iOS转盘效果，轮盘抽奖效果的实现，转盘可以暂停，旋转，已经快速旋转抽奖，选中的效果指向正上方。

效果图：

工程文件目录：

核心代码：

//// ViewController.m// 转盘效果//// Created by llkj on 2017/8/31.// Copyright © 2017年 LayneCheung. All rights reserved.//#import "ViewController.h"#import "WheelView.h"@interface ViewController ()@property (nonatomic, weak) WheelView *wheelV;@end@implementation ViewController- (void)viewDidLoad { [super viewDidLoad]; WheelView *wheelV = [WheelView wheelView]; wheelV.center = self.view.center; self.wheelV = wheelV; [self.view addSubview:wheelV];}- (IBAction)rotation:(id)sender { [self.wheelV rotation];}- (IBAction)stop:(id)sender { [self.wheelV stop];}- (void)didReceiveMemoryWarning { [super didReceiveMemoryWarning]; // Dispose of any resources that can be recreated.}@end

WheelView文件

//// WheelView.h// 转盘效果//// Created by llkj on 2017/8/31.// Copyright © 2017年 LayneCheung. All rights reserved.//#import <UIKit/UIKit.h>@interface WheelView : UIView+ (instancetype)wheelView;- (void)rotation;- (void)stop;@end//// WheelView.m// 转盘效果//// Created by llkj on 2017/8/31.// Copyright © 2017年 LayneCheung. All rights reserved.//#import "WheelView.h"#import "WheelBtn.h"#define angle2Rad(angle) ((angle) / 180.0 * M_PI)@interface WheelView ()<CAAnimationDelegate>@property (weak, nonatomic) IBOutlet UIImageView *contentV;@property (nonatomic, weak) UIButton *selectBtn;@property (nonatomic, strong) CADisplayLink *link;@end@implementation WheelView- (CADisplayLink *)link { if (_link == nil) { CADisplayLink *link = [CADisplayLink displayLinkWithTarget:self selector:@selector(update)]; [link addToRunLoop:[NSRunLoop mainRunLoop] forMode:NSDefaultRunLoopMode]; _link = link; } return _link;}+ (instancetype)wheelView { return [[[NSBundle mainBundle] loadNibNamed:@"WheelView" owner:nil options:nil] lastObject];}- (instancetype)initWithFrame:(CGRect)frame{ self = [super initWithFrame:frame]; if (self) { self = [[[NSBundle mainBundle] loadNibNamed:@"WheelView" owner:nil options:nil] lastObject]; } return self;}- (void)awakeFromNib { [super awakeFromNib]; CGFloat btnW = 68; CGFloat btnH = 143; CGFloat angle = 0; //加载原始大图片 UIImage *oriImage = [UIImage imageNamed:@"LuckyAstrology"]; //加载原始选中的大图片 UIImage *oriSelImg = [UIImage imageNamed:@"LuckyAstrologyPressed"]; CGFloat X = 0; CGFloat Y = 0; CGFloat sacle = [UIScreen mainScreen].scale; CGFloat clipW = oriImage.size.width / 12.0 * sacle; CGFloat clipH = oriImage.size.height * sacle; for (int i = 0; i < 12; i ++) { WheelBtn *btn = [WheelBtn buttonWithType:UIButtonTypeCustom]; btn.bounds = CGRectMake(0, 0, btnW, btnH); //按钮正常状态图片 X = i * clipW; //给定一张图片截取指定区域内的图片 CGImageRef clipImg = CGImageCreateWithImageInRect(oriImage.CGImage, CGRectMake(X, Y, clipW, clipH)); [btn setImage:[UIImage imageWithCGImage:clipImg] forState:UIControlStateNormal]; //按钮选中状态图片 CGImageRef clipSelImg = CGImageCreateWithImageInRect(oriSelImg.CGImage, CGRectMake(X, Y, clipW, clipH)); [btn setImage:[UIImage imageWithCGImage:clipSelImg] forState:UIControlStateSelected]; [btn setBackgroundImage:[UIImage imageNamed:@"LuckyRototeSelected"] forState:UIControlStateSelected]; btn.layer.anchorPoint = CGPointMake(0.5, 1); btn.layer.position = CGPointMake(self.bounds.size.width * 0.5, self.bounds.size.height * 0.5); btn.transform = CGAffineTransformMakeRotation(angle2Rad(angle)); angle += 30; [btn addTarget:self action:@selector(btnClick:) forControlEvents:UIControlEventTouchUpInside]; [self.contentV addSubview:btn]; //默认第一个按钮选中 if (i == 0) { [self btnClick:btn]; } }}- (void)btnClick:(UIButton *)btn { //1.让当前选中的按钮取消选中 self.selectBtn.selected = NO; //2.让当前点击的按钮成为选中状态 btn.selected = YES; //3.当前点击的按钮成为选中状态 self.selectBtn = btn;}- (void)rotation { self.link.paused = NO;}- (void)stop { self.link.paused = YES;}- (void)update { self.contentV.transform = CGAffineTransformRotate(self.contentV.transform, M_PI / 300.0);}- (IBAction)start:(id)sender { //快速转几圈 CABasicAnimation *anim = [CABasicAnimation animation]; anim.keyPath = @"transform.rotation"; anim.toValue = @(M_PI * 4); anim.duration = 0.5; anim.repeatCount = 1; anim.delegate = self; [self.contentV.layer addAnimation:anim forKey:nil];}- (void)animationDidStop:(CAAnimation *)anim finished:(BOOL)flag { CGAffineTransform transform = self.selectBtn.transform; //获取当前选中按钮的旋转角度 CGFloat angle = atan2(transform.b, transform.a); //动画结束时当前选中的按钮指向最上方 self.contentV.transform = CGAffineTransformMakeRotation(-angle);}@end

WheelBtn.m

//// WheelBtn.m// 转盘效果//// Created by llkj on 2017/8/31.// Copyright © 2017年 LayneCheung. All rights reserved.//#import "WheelBtn.h"@implementation WheelBtn- (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event { CGRect rect = CGRectMake(0, 0, self.bounds.size.width, self.bounds.size.height * 0.5); if (CGRectContainsPoint(rect, point)) { // 在指定的范围内 return [super hitTest:point withEvent:event]; } else { return nil; }}//取消按钮高亮状态做的事- (void)setHighlighted:(BOOL)highlighted {}//返回当前按钮中的image位置和尺寸- (CGRect)imageRectForContentRect:(CGRect)contentRect { return CGRectMake((contentRect.size.width - 40) *0.5, 20, 40, 48);}//返回当前按钮中的Label位置和尺寸//- (CGRect)titleRectForContentRect:(CGRect)contentRect{////}@end

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。