本文實例為大家介紹了iOS時鐘開發過程，供大家參考，具體內容如下
思路就是利用CALayer的隱式動畫來實現。因為UIView的非根層也就是手動創建的layer在其屬性發生變化時會默認會產生動畫效果，這些屬性也叫作可動畫屬性。比如bounds、backgroundColor、position。
時鐘里面表盤就是一個UIView，而三根針就是三個手動創建的layer。
先在storyboard上弄一個UIImageView，設置表盤圖片
然后在viewDidLoad中初始化三根針，并設置定時器，獲取當前時間，將當前時間對應的時針分針秒針分別指向對應的角度。
//// ViewController.m// 時鐘效果//// Created by Daniel on 16/4/7.// Copyright © 2016年 Daniel. All rights reserved.// #define kClockWH _clockView.bounds.size.width //一秒鐘秒針轉多少度#define preSecondA 6 //一分鐘分針轉多少度#define preMinuteA 6 //一小時時針轉多少度#define preHourA 30 //每分鐘時針轉多少度#define preHourMinute 0.5 //每秒鐘分針轉多少度#define preMinuteSecond 0.1 #define angle2raditon(a) ((a) / 180.0 * M_PI) #import "ViewController.h" @interface ViewController ()@property (weak, nonatomic) IBOutlet UIImageView *clockView; /** 秒針 */@property(nonatomic, strong) CALayer *secondL; /** 分針 */@property(nonatomic, strong) CALayer *minuteL; /** 時針 */@property(nonatomic, strong) CALayer *hourL; @end @implementation ViewController - (void)viewDidLoad { [super viewDidLoad]; //添加時針 [self setUpHourLayer]; //添加分針 [self setUpMinuteLayer]; //添加秒針 [self setUpSecondLayer]; //添加定時器 [NSTimer scheduledTimerWithTimeInterval:1 target:self selector:@selector(timeChange) userInfo:nil repeats:YES]; //開始運行時就獲取時間，這樣在啟動時就不會有停頓的感覺 [self timeChange]; } - (void)timeChange { //獲取當前系統時間 NSCalendar *calendar = [NSCalendar currentCalendar]; NSDateComponents *cmp = [calendar components:NSCalendarUnitSecond | NSCalendarUnitMinute | NSCalendarUnitHour fromDate:[NSDate date]]; //獲取秒 NSInteger second = cmp.second; //獲取分 NSInteger minute = cmp.minute; //獲取小時 NSInteger hour = cmp.hour; //計算秒針轉多少度 CGFloat secondA = second * preSecondA; //計算分針轉多少度 CGFloat minuteA = minute * preMinuteA + second * preMinuteSecond; //計算時針轉多少度 CGFloat hourA = hour * preHourA + minute * preHourMinute; //旋轉秒針 _secondL.transform = CATransform3DMakeRotation(angle2raditon(secondA), 0, 0, 1); //旋轉分針 _minuteL.transform = CATransform3DMakeRotation(angle2raditon(minuteA), 0, 0, 1); //旋轉時針 _hourL.transform = CATransform3DMakeRotation(angle2raditon(hourA), 0, 0, 1); } #pragma mark - 初始化時針- (void)setUpHourLayer { CALayer *hourL = [CALayer layer]; //設置秒針背景色 hourL.backgroundColor = [UIColor blackColor].CGColor; //設置秒針錨點 hourL.anchorPoint = CGPointMake(0.5, 1); //設置秒針錨點在父控件的位置 hourL.position = CGPointMake(kClockWH * 0.5, kClockWH * 0.5); hourL.cornerRadius = 4; //設置秒針bounds hourL.bounds = CGRectMake(0, 0, 4, kClockWH * 0.5 - 40); //把秒針添加到clockView圖層上 [_clockView.layer addSublayer:hourL]; _hourL = hourL; } #pragma mark - 初始化分針- (void)setUpMinuteLayer { CALayer *minuteL = [CALayer layer]; //設置秒針背景色 minuteL.backgroundColor = [UIColor blackColor].CGColor; //設置秒針錨點 minuteL.anchorPoint = CGPointMake(0.5, 1); //設置秒針錨點在父控件的位置 minuteL.position = CGPointMake(kClockWH * 0.5, kClockWH * 0.5); minuteL.cornerRadius = 4; //設置秒針bounds minuteL.bounds = CGRectMake(0, 0, 4, kClockWH * 0.5 - 20); //把秒針添加到clockView圖層上 [_clockView.layer addSublayer:minuteL]; _minuteL = minuteL; } #pragma mark - 初始化秒針- (void)setUpSecondLayer { CALayer *secondL = [CALayer layer]; //設置秒針背景色 secondL.backgroundColor = [UIColor redColor].CGColor; //設置秒針錨點 secondL.anchorPoint = CGPointMake(0.5, 1); //設置秒針錨點在父控件的位置 secondL.position = CGPointMake(kClockWH * 0.5, kClockWH * 0.5); //設置秒針bounds secondL.bounds = CGRectMake(0, 0, 1.5, kClockWH * 0.5 - 20); //把秒針添加到clockView圖層上 [_clockView.layer addSublayer:secondL]; _secondL = secondL; } @end 效果圖：
以上就是本文的全部內容，希望對大家學習IOS程序設計有所幫助。
