iOS - 位置處理

簡介

在 iOS 系統中，我們可以很容易地找到用戶的當前位置，用戶允許應用程序訪問的核心位置框架的幫助信息。

涉及的步驟

1. 創建一個簡單的 View based application.

2. 選擇項目文件，然後選擇目標，然後添加如下所示 CoreLocation.framework。

3. 添加兩個標籤在ViewController.xib並創建 ibOutlets 命名標籤分別爲 latitudeLabel 和 longitudeLabel。

4. 現在創建一個新的文件，通過選擇 File-> New -> File... -> select Objective-C類並點擊 next

5. 命名類爲 LocationHandler ，並設置爲 NSObject 的子類.

6. 選擇創建

7. 更新 LocationHandler.h 如下

#import <Foundation/Foundation.h> #import <CoreLocation/CoreLocation.h> @protocol LocationHandlerDelegate <NSObject> @required -(void) didUpdateToLocation:(CLLocation*)newLocation
fromLocation:(CLLocation*)oldLocation; @end @interface LocationHandler : NSObject<CLLocationManagerDelegate> { CLLocationManager *locationManager; } @property(nonatomic,strong) id<LocationHandlerDelegate> delegate; +(id)getSharedInstance; -(void)startUpdating; -(void) stopUpdating; @end

8. 現在更新LocationHandler.m如下：

#import "LocationHandler.h" static LocationHandler *DefaultManager = nil; @interface LocationHandler() -(void)initiate; @end @implementation LocationHandler +(id)getSharedInstance{ if (!DefaultManager) { DefaultManager = [[self allocWithZone:NULL]init]; [DefaultManager initiate]; } return DefaultManager; } -(void)initiate{ locationManager = [[CLLocationManager alloc]init]; locationManager.delegate = self; } -(void)startUpdating{ [locationManager startUpdatingLocation]; } -(void) stopUpdating{ [locationManager stopUpdatingLocation]; } -(void)locationManager:(CLLocationManager *)manager didUpdateToLocation: (CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation{ if ([self.delegate respondsToSelector:@selector (didUpdateToLocation:fromLocation:)]) { [self.delegate didUpdateToLocation:oldLocation
fromLocation:newLocation]; } } @end

9. 如下更新 ViewController.h 我們實現了 LocationHandler 委託並創建兩個 ibOutlets。

#import <UIKit/UIKit.h> #import "LocationHandler.h" @interface ViewController : UIViewController<LocationHandlerDelegate> { IBOutlet UILabel *latitudeLabel; IBOutlet UILabel *longitudeLabel; } @end

10. 更新 ViewController.m 如下：

#import "ViewController.h" @interface ViewController () @end @implementation ViewController - (void)viewDidLoad { [super viewDidLoad]; [[LocationHandler getSharedInstance]setDelegate:self]; [[LocationHandler getSharedInstance]startUpdating]; } - (void)didReceiveMemoryWarning { [super didReceiveMemoryWarning]; // Dispose of any resources that can be recreated. } -(void)didUpdateToLocation:(CLLocation *)newLocation
fromLocation:(CLLocation *)oldLocation{ [latitudeLabel setText:[NSString stringWithFormat: @"Latitude: %f",newLocation.coordinate.latitude]]; [longitudeLabel setText:[NSString stringWithFormat: @"Longitude: %f",newLocation.coordinate.longitude]]; } @end

輸出

現在，當我們運行程序時，我們會得到下面的輸出。