iOS系统授权开发

iOS系统开发中，最常用的系统授权，莫过于系统通知,用户相册,位置服务了，这篇文章将简单讲解这三项功能的开发，并附带我写的一个，统一管理系统授权。

注：本文和项目基于iOS 8.0及以上系统框架，低版本框架接口略有不同。

系统通知授权

系统通知方法在UIApplication类方法中，其中使用isRegisteredForRemoteNotifications获取本地推送授权状态。

+ (UIUserNotificationType)notificationType{    UIApplication* application = [UIApplication sharedApplication];    return  [application currentUserNotificationSettings].types;}

这里授权状态的枚举类型有

1. UIUserNotificationTypeNone 无授权

2. UIUserNotificationTypeBadge 角标

3. UIUserNotificationTypeSound 声音

4. UIUserNotificationTypeAlert 通知

原枚举如下

typedef NS_OPTIONS(NSUInteger, UIUserNotificationType) {    UIUserNotificationTypeNone    = 0,      // the application may not present any UI upon a notification being received    UIUserNotificationTypeBadge   = 1 << 0, // the application may badge its icon upon a notification being received    UIUserNotificationTypeSound   = 1 << 1, // the application may play a sound upon a notification being received    UIUserNotificationTypeAlert   = 1 << 2, // the application may display an alert upon a notification being received} NS_ENUM_AVAILABLE_IOS(8_0) __TVOS_PROHIBITED;

授权方法

UIUserNotificationType type = UIUserNotificationTypeBadge | UIUserNotificationTypeAlert | UIUserNotificationTypeSound;UIUserNotificationSettings *setting = [UIUserNotificationSettings settingsForTypes:type categories:nil];[[UIApplication sharedApplication] registerUserNotificationSettings:setting];

注意，每一项授权，一旦用户拒绝，必须前往设置的相关APP页面开启。APP内跳设置的方法是

[[UIApplication sharedApplication] openURL:[NSURL URLWithString:UIApplicationOpenSettingsURLString]];

注册本地通知也是有回调的，实现UIApplicationDelegate的didRegisterUserNotificationSettings方法。

- (void)application:(UIApplication *)application didRegisterUserNotificationSettings:(UIUserNotificationSettings *)notificationSettings{ }

相应的也有失败的回调。

系统相册授权

8.0系统版本以后，框架中加入了Photos.framework框架，当然是用UIImagePickerController同样会提醒用户授权使用相册或相机，这里介绍一下Photos框架的授权。

相册权限状态

+ (PHAuthorizationStatus)photoAccesStatus{    return [PHPhotoLibrary authorizationStatus];}

typedef NS_ENUM(NSInteger, PHAuthorizationStatus) {    PHAuthorizationStatusNotDetermined = 0, // User has not yet made a choice with regards to this application    PHAuthorizationStatusRestricted,        // This application is not authorized to access photo data.                                            // The user cannot change this application’s status, possibly due to active restrictions                                            //   such as parental controls being in place.    PHAuthorizationStatusDenied,            // User has explicitly denied this application access to photos data.    PHAuthorizationStatusAuthorized         // User has authorized this application to access photos data.} NS_AVAILABLE_IOS(8_0);

这里授权状态有四个状态

1. PHAuthorizationStatusNotDetermined 未授权

2. PHAuthorizationStatusRestricted 授权中

3. PHAuthorizationStatusDenied 拒绝

4. PHAuthorizationStatusAuthorized 已授权

授权Block方法

[PHPhotoLibrary requestAuthorization:^(PHAuthorizationStatus status) {  }];

位置服务授权

位置服务授权稍微复杂一点点，8.0以后，进行位置服务授权要注意一点是，需要在工程的Info.plist文件中加入NSLocationAlwaysUsageDescription字段。字段中是开发者展示给用户的位置服务的使用场景介绍，或者是请求授权的描述。如果不添加这个字段，授权接口无任何反应。

状态接口

+ (CLAuthorizationStatus)positionAuthorizationStatus{    return [CLLocationManager authorizationStatus];}

授权方法

+ (void)authorizedPosition:(CLLocationManager *)manager{    [manager requestAlwaysAuthorization];}

注意这里传入的manager一定要是个property,如果是一个局部变量，大括号结束，释放掉了，授权就会消失，就会出现授权框一闪而过的现象。

PermissionScope 项目

PermissionScope()是一个超级屌，并且好用的开源控件，用来向用户申请系统授权。如果你有使用cocospod管理工具，这样加入use_frameworks!,因为PermissionScope是swift写的，需要编译成Framework才可以给ObjC用。

use_frameworks!pod 'PermissionScope'

具体用法

PermissionScope* scope = [[PermissionScope alloc] initWithBackgroundTapCancels:YES];            //[scope addPermission:[[CameraPermission alloc] init] message:@"请求使用您的相机"];//[scope addPermission:[[BluetoothPermission alloc] init] message:@"请求使用您的蓝牙"];//[scope addPermission:[[ContactsPermission alloc] init] message:@"请求使用您的通讯录"];//[scope addPermission:[[EventsPermission alloc] init] message:@"请求使用您的日历"];[scope addPermission:[[LocationAlwaysPermission alloc] init] message:@"请求使用您的位置"];[scope addPermission:[[MicrophonePermission alloc] init] message:@"请求使用您的麦克风"];[scope addPermission:[[NotificationsPermission alloc] initWithNotificationCategories:nil] message:@"请求使用通知服务"];             [scope show:^(BOOL s, NSArray
    
      * _Nonnull results) {                            } cancelled:^(NSArray
     
       * _Nonnull canceled) {                            }];
     
    

这个例子很明了吧，但要注意几点

1. 最少要添加一个Permission

2. 最多添加3个Permission

3. 8.0以后，进行位置服务授权，需要在工程的Info.plist文件中加入NSLocationAlwaysUsageDescription字段。