iOS 系統受權開發

iOS系統受權開發

iOS系統開發中，最經常使用的系統受權，莫過於系統通知,用戶相冊,位置服務了，這篇文章將簡單講解這三項功能的開發，並附帶我寫的一個開源項目，統一管理系統受權。

注：本文和項目基於iOS 8.0及以上系統框架，低版本框架接口略有不一樣。

系統通知受權

系統通知方法在UIApplication類方法中，其中使用isRegisteredForRemoteNotifications獲取本地推送受權狀態。

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

這裏受權狀態的枚舉類型有

1. UIUserNotificationTypeNone 無受權

2. UIUserNotificationTypeBadge 角標

3. UIUserNotificationTypeSound 聲音

4. UIUserNotificationTypeAlert 通知

原枚舉以下

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;

受權方法

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

注意，每一項受權，一旦用戶拒絕，必須前往設置的相關APP頁面開啓。APP內跳設置的方法是

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

註冊本地通知也是有回調的，實現UIApplicationDelegate的didRegisterUserNotificationSettings方法。

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

相應的也有失敗的回調。

系統相冊受權

8.0系統版本之後，框架中加入了Photos.framework框架，固然是用UIImagePickerController一樣會提醒用戶受權使用相冊或相機，這裏介紹一下Photos框架的受權。

相冊權限狀態

+ (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);

這裏受權狀態有四個狀態

1. PHAuthorizationStatusNotDetermined 未受權

2. PHAuthorizationStatusRestricted 受權中

3. PHAuthorizationStatusDenied 拒絕

4. PHAuthorizationStatusAuthorized 已受權

受權Block方法

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

位置服務受權

位置服務受權稍微複雜一點點，8.0之後，進行位置服務受權要注意一點是，須要在工程的Info.plist文件中加入NSLocationAlwaysUsageDescription字段。字段中是開發者展現給用戶的位置服務的使用場景介紹，或者是請求受權的描述。若是不添加這個字段，受權接口無任何反應。

狀態接口

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

受權方法

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

注意這裏傳入的manager必定要是個property,若是是一個局部變量，大括號結束，釋放掉了，受權就會消失，就會出現受權框一閃而過的現象。

開源項目 DeviceAccessViewController

PermissionScope 項目

PermissionScope(Github)是一個超級屌，而且好用的開源控件，用來向用戶申請系統受權。若是你有使用cocospod管理工具，這樣加入use_frameworks!,由於PermissionScope是swift寫的，須要編譯成Framework才能夠給ObjC用。

use_frameworks!
pod 'PermissionScope'

具體用法

PermissionScope* scope = [[PermissionScope alloc] initWithBackgroundTapCancels:YES];
            
//[scope addPermission:[[CameraPermission alloc] init] message:@"請求使用您的相機"];
//[scope addPermission:[[BluetoothPermission alloc] init] message:@"請求使用您的藍牙"];
//[scope addPermission:[[ContactsPermission alloc] init] message:@"請求使用您的通信錄"];
//[scope addPermission:[[EventsPermission alloc] init] message:@"請求使用您的日曆"];
[scope addPermission:[[LocationAlwaysPermission alloc] init] message:@"請求使用您的位置"];
[scope addPermission:[[MicrophonePermission alloc] init] message:@"請求使用您的麥克風"];
[scope addPermission:[[NotificationsPermission alloc] initWithNotificationCategories:nil] message:@"請求使用通知服務"];
            
 [scope show:^(BOOL s, NSArray<PermissionResult *> * _Nonnull results) {
                
            } cancelled:^(NSArray<PermissionResult *> * _Nonnull canceled) {
                
            }];

這個例子很明瞭吧，但要注意幾點

1. 最少要添加一個Permission

2. 最多添加3個Permission

3. 8.0之後，進行位置服務受權，須要在工程的Info.plist文件中加入NSLocationAlwaysUsageDescription字段。