iOS動畫之漂亮的時鐘

在ios中預設是繞著中心點旋轉的，因為錨點預設在圖層的中點，要想繞著下邊中心點轉，需要改變圖層錨點的位置。根據錨點，設定position座標，為時鐘的中點。思考秒針旋轉的角度，怎麼知道當前秒針旋轉到哪，當前秒針旋轉的角度 = 當前秒數 * 每秒轉多少°。

1> 計算一秒轉多少° 360 * 60 = 6

2> 獲取當前秒數，通過日曆物件，獲取日期組成成分 nscalendar -> nsdatecomponents -> 獲取當前秒數每隔一秒，獲取最新秒數，更新時鐘。

分鐘一樣的做法時鐘也一樣每一分鐘，時鐘也需要旋轉，60分鐘 -> 1小時 - > 30° ==》每分鐘 30 / 60.0 一分鐘時針轉0.5° 把時針和秒針頭尾變尖，設定圓角半徑

#import viewcontroller.h

//獲得當前的年月日時分秒

#define currentsec [[nscalendar currentcalendar] component:nscalendarunitsecond fromdate:[nsdate date]]

#define currentmin [[nscalendar currentcalendar] component:nscalendarunitminute fromdate:[nsdate date]]

#define currenthour [[nscalendar currentcalendar] component:nscalendarunithour fromdate:[nsdate date]]

#define currentday [[nscalendar currentcalendar] component:nscalendarunitday fromdate:[nsdate date]]

#define currentmonth [[nscalendar currentcalendar] component:nscalendarunitmonth fromdate:[nsdate date]]

#define currentyear [[nscalendar currentcalendar] component:nscalendarunityear fromdate:[nsdate date]]

//角度轉換成弧度

#define angel(x) x/180.0 * m_pi

#define kperseconda angel(6)

#define kperminutea angel(6)

#define kperhoura angel(30)

#define kperhourminutea angel(0.5)

@inte***ce viewcontroller ()

@property (nonatomic,strong) uiimageview *imageclock;

@property (nonatomic,strong) calayer *layersec;

@property (nonatomic,strong) calayer *layermin;

@property (nonatomic,strong) calayer *layerhour;

@end

@implementation viewcontroller

- (void)viewdidload

- (void)timechange

- (uiimageview *)imageclock

return _imageclock;

}- (calayer *)layersec

return _layersec;

}- (calayer *)layermin

return _layermin;

}- (calayer *)layerhour

return _layerhour;

}