Android M 权限:对 shouldShowRequestPermissionRationale() 函数的用法感到困惑

Posted

技术标签:

【中文标题】Android M 权限:对 shouldShowRequestPermissionRationale() 函数的用法感到困惑【英文标题】:Android M Permissions : Confused on the usage of shouldShowRequestPermissionRationale() function 【发布时间】:2015-11-27 15:07:01 【问题描述】:

我正在浏览有关 android M 中新权限模型的官方文档。它谈到了 shouldShowRequestPermissionRationale() 函数,如果应用程序之前请求过此权限并且用户拒绝了该请求,则该函数返回 true。如果用户过去拒绝了权限请求并选择了不再询问选项,则此方法返回false

但是我们如何区分以下两种情况呢?

案例1:应用没有权限,用户之前也没有被请求权限。在这种情况下,shouldShowRequestPermissionRationale() 将返回 false,因为这是我们第一次询问用户。

案例 2:用户拒绝了权限并选择了“不再询问”,在这种情况下 shouldShowRequestPermissionRationale() 也会返回 false。

我想在案例 2 中将用户发送到应用程序的设置页面。如何区分这两种情况?

【问题讨论】:

接受的答案很好。作为替代方案,您还可以使用共享首选项来了解应用程序之前是否请求过权限。只是把它扔在那里,以防它更适用于其他人的情况。 还有一种情况3:用户已被请求并授予/拒绝权限,但已使用权限设置恢复为“每次询问”。测试表明 shouldShowRequestPermissionRationale() 在这种情况下返回 false,这将损害任何依赖“我之前问过”标志的代码。 这里是一个 google 示例,展示了 Android 上 permissions 中的最佳实践。 github.com/android/permissions-samples @itabdullah Google 的示例代码毫无用处,因为他们甚至没有考虑“用户上次是否永久拒绝许可”这种极有可能的用例。 :-/ 典型 【参考方案1】:

M Preview 1 之后,如果对话框第一次显示,则没有Never ask again复选框。

如果用户拒绝了权限请求,Never ask again 复选框会出现在权限对话框中第二次请求权限。

所以逻辑应该是这样的:

    请求权限:

    if (ContextCompat.checkSelfPermission(context, Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) 
        ActivityCompat.requestPermissions(context, new String[]Manifest.permission.WRITE_EXTERNAL_STORAGE, REQUEST_CODE);
     else 
        //Do the stuff that requires permission...
    
    

    检查权限是否在onRequestPermissionsResult 中被拒绝或授予。

    如果之前该权限被拒绝,这一次在权限对话框中会有一个不再询问复选框。

    致电shouldShowRequestPermissionRationale 以查看用户是否选中了不再询问shouldShowRequestPermissionRationale 方法仅在用户选择不再询问或设备策略禁止应用拥有该权限时返回 false:

    if (grantResults.length > 0)
        if(grantResults[0] == PackageManager.PERMISSION_GRANTED) 
            //Do the stuff that requires permission...
        else if (grantResults[0] == PackageManager.PERMISSION_DENIED)
            // Should we show an explanation?
            if (ActivityCompat.shouldShowRequestPermissionRationale(context, Manifest.permission.WRITE_EXTERNAL_STORAGE)) 
                //Show permission explanation dialog...
            else
                //Never ask again selected, or device policy prohibits the app from having that permission.
                //So, disable that feature, or fall back to another situation...
            
        
    
    

因此,您不必跟踪用户是否选中了不再询问

【讨论】:

澄清一点,如果用户从未被请求权限(即第一次运行应用程序),shouldShowRequestPermissionRationale() 也将返回 false。如果您遵循所提供示例的逻辑,您将不会遇到这种情况。但是,低于 2 的措辞有点误导。 我不确定,这似乎有缺陷。我们应该如何知道这是否是第一次询问用户?我必须跟踪用户是否被问到,如果他这样做了,那么我必须颠倒逻辑。对我来说没有任何意义。 我认为值得注意的是,您在ActivityCompat.shouldShowRequestPermissionRationale(...) 中传递context 的位置实际上是Activity 类型的参数。可能不会影响你们所有人,但在我的情况下会影响。 这安卓逻辑太蠢了!它迫使我在回调中调用 should 并将其计数器值保存在 NVM 中,只是为了知道我是否需要在下次打开应用程序时再次提示请求! ...哇(捂脸)...仅拨打一个电话返回状态枚举是否太难了?? 我认为这是谷歌的一大失败。官方文档指出,应该在检查权限之前调用 shouldShowRequestPermissionRationale()(参见developer.android.com/training/permissions/requesting#explain),但 *** 中的所有答案都会在 onRequestPermissionResult() 中调用它,以区分用户是否单击了“不再询问”。 【参考方案2】:

我有同样的问题,我想通了。为了让生活更简单,我编写了一个 util 类来处理运行时权限。

public class PermissionUtil 
    /*
    * Check if version is marshmallow and above.
    * Used in deciding to ask runtime permission
    * */
    public static boolean shouldAskPermission() 
        return (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M);
    
private static boolean shouldAskPermission(Context context, String permission)
        if (shouldAskPermission()) 
            int permissionResult = ActivityCompat.checkSelfPermission(context, permission);
            if (permissionResult != PackageManager.PERMISSION_GRANTED) 
                return true;
            
        
        return false;
    
public static void checkPermission(Context context, String permission, PermissionAskListener listener)
/*
        * If permission is not granted
        * */
        if (shouldAskPermission(context, permission))
/*
            * If permission denied previously
            * */
            if (((Activity) context).shouldShowRequestPermissionRationale(permission)) 
                listener.onPermissionPreviouslyDenied();
             else 
                /*
                * Permission denied or first time requested
                * */
if (PreferencesUtil.isFirstTimeAskingPermission(context, permission)) 
                    PreferencesUtil.firstTimeAskingPermission(context, permission, false);
                    listener.onPermissionAsk();
                 else 
                    /*
                    * Handle the feature without permission or ask user to manually allow permission
                    * */
                    listener.onPermissionDisabled();
                
            
         else 
            listener.onPermissionGranted();
        
    
/*
    * Callback on various cases on checking permission
    *
    * 1.  Below M, runtime permission not needed. In that case onPermissionGranted() would be called.
    *     If permission is already granted, onPermissionGranted() would be called.
    *
    * 2.  Above M, if the permission is being asked first time onPermissionAsk() would be called.
    *
    * 3.  Above M, if the permission is previously asked but not granted, onPermissionPreviouslyDenied()
    *     would be called.
    *
    * 4.  Above M, if the permission is disabled by device policy or the user checked "Never ask again"
    *     check box on previous request permission, onPermissionDisabled() would be called.
    * */
    public interface PermissionAskListener 
/*
        * Callback to ask permission
        * */
        void onPermissionAsk();
/*
        * Callback on permission denied
        * */
        void onPermissionPreviouslyDenied();
/*
        * Callback on permission "Never show again" checked and denied
        * */
        void onPermissionDisabled();
/*
        * Callback on permission granted
        * */
        void onPermissionGranted();
    

PreferenceUtil方法如下。

public static void firstTimeAskingPermission(Context context, String permission, boolean isFirstTime)
SharedPreferences sharedPreference = context.getSharedPreferences(PREFS_FILE_NAME, MODE_PRIVATE;
 sharedPreference.edit().putBoolean(permission, isFirstTime).apply();
 
public static boolean isFirstTimeAskingPermission(Context context, String permission)
return context.getSharedPreferences(PREFS_FILE_NAME, MODE_PRIVATE).getBoolean(permission, true);

现在,您只需使用带有适当参数的方法 checkPermission

这是一个例子,

PermissionUtil.checkPermission(context, Manifest.permission.WRITE_EXTERNAL_STORAGE,
                    new PermissionUtil.PermissionAskListener() 
                        @Override
                        public void onPermissionAsk() 
                            ActivityCompat.requestPermissions(
                                    thisActivity,
              new String[]Manifest.permission.READ_CONTACTS,
                            REQUEST_EXTERNAL_STORAGE
                            );
                        
@Override
                        public void onPermissionPreviouslyDenied() 
                       //show a dialog explaining permission and then request permission
                        
@Override
                        public void onPermissionDisabled() 
Toast.makeText(context, "Permission Disabled.", Toast.LENGTH_SHORT).show();
                        
@Override
                        public void onPermissionGranted() 
                            readContacts();
                        
                    );

案例1:应用没有权限,用户也没有 之前请求过许可。在这种情况下, shouldShowRequestPermissionRationale() 将返回 false,因为这 是我们第一次询问用户。

案例 2:用户拒绝了权限并选择了“不要询问” 再次”,在这种情况下, shouldShowRequestPermissionRationale() 也会 返回 false。

我想在案例 2 中将用户发送到应用程序的设置页面。 如何区分这两种情况?

对于案例 1,您将在 onPermissionAsk 上获得回调,对于案例 2,您将在 onPermissionDisabled 上获得回调。

编码愉快:)

【讨论】:

很好的解释兄弟。遵循您完全相同的程序。 :) 这个Activity我要填什么? public void onPermissionAsk() ActivityCompat.requestPermissions( thisActivity, ... . @Mardymar thisActivity 只不过是YourActivity.this 如何处理多个权限以及如何将这段代码集成到片段中。 谢谢 - 在所有答案中(包括被接受/最赞成的答案),您是唯一真正回答问题的人【参考方案3】:

更新

我相信下面CanC 的answer 是正确的,应该遵循。唯一确定的方法是使用 shouldShowPermissionRationale 在 onRequestPermissionResult 回调中验证这一点。

==

我原来的答案:

我发现的唯一方法是自行跟踪这是否是第一次(例如,使用共享偏好)。如果不是第一次,那就用shouldShowRequestPermissionRationale()来区分。

另见:Android M - check runtime permission - how to determine if the user checked "Never ask again"?

【讨论】:

是的,即使我同意 CanC 的方法是应该遵循的方法。我会将其标记为已接受的答案。【参考方案4】:

按照我的理解,shouldShowRequestPermissionRationale() 在后台运行了许多用例,并通知应用是否显示所请求权限的解释。

运行时权限背后的想法是,大多数时候,用户会对权限请求说“是”。这样,用户只需单击一下即可。当然,该请求应在正确的上下文中使用 - 即在按下“相机”按钮时请求相机权限。

如果用户拒绝了请求,但一段时间后再次按下“相机”按钮,shouldShowRequestPermissionRationale() 将返回 true,因此应用程序可以显示一些有意义的解释为什么请求权限,以及为什么应用程序没有它就无法正常工作。通常,您会在该对话框窗口中显示一个按钮来再次拒绝/稍后决定,以及一个按钮来授予权限。基本原理对话框中的授予权限按钮应再次启动权限请求。这次用户还将有一个“不再显示”复选框。如果他决定选择它并再次拒绝该权限,它会通知 Android 系统用户和应用程序不在同一页面上。该操作将产生两个后果 - shouldShowRequestPermissionRationale() 将始终返回 false,并且 requestPermissions() 方法将不显示任何对话框,但会直接向 onRequestPermissionsResult 回调返回拒绝。

但还有另一种可能的情况,可以使用 onRequestPermissionsResult。例如,某些设备可能具有禁用相机的设备策略(适用于 CIA、DARPA 等)。在这些设备上,onRequestPermissionsResult 将始终返回 false,并且 requestPermissions() 方法将静默拒绝请求。

这是我通过与 Android 框架产品经理 Ben Poiesz 一起收听播客时收集到的信息。http://androidbackstage.blogspot.jp/2015/08/episode-33-permission-mission.html

【讨论】:

【参考方案5】:

如果有人愿意,请发布另一个选项。您可以使用谷歌自己提供的EasyPermissions,如所说的“简化Android M系统权限”。

那你就不用直接处理shouldShowRequestPermissionRationale了。

【讨论】:

为什么我之前没有看到这个项目 :) EasyPermissions 的问题几乎没有改变。在内部询问permissionPermanentlyDenied 只是调用shouldShowPermissionsRationale 并在从未请求用户授予权限的情况下返回true【参考方案6】:

如果有人对 Kotlin 解决方案感兴趣,我将 @muthuraj 的答案重构为在 Kotlin 中。还对其进行了一些现代化改造,使其具有完成块而不是侦听器。

PermissionUtil

object PermissionUtil 
    private val PREFS_FILE_NAME = "preference"

    fun firstTimeAskingPermission(context: Context, permission: String, isFirstTime: Boolean) 
        val sharedPreference = context.getSharedPreferences(PREFS_FILE_NAME, MODE_PRIVATE)
        sharedPreference.preferences.edit().putBoolean(permission,
                isFirstTime).apply()
    

    fun isFirstTimeAskingPermission(context: Context, permission: String): Boolean 
        val sharedPreference = context.getSharedPreferences(PREFS_FILE_NAME, MODE_PRIVATE)
        return sharedPreference.preferences.getBoolean(permission,
                true)
    

PermissionHandler

enum class CheckPermissionResult 
    PermissionAsk,
    PermissionPreviouslyDenied,
    PermissionDisabled,
    PermissionGranted


typealias PermissionCheckCompletion = (CheckPermissionResult) -> Unit


object PermissionHandler 

    private fun shouldAskPermission(context: Context, permission: String): Boolean 
        return ContextCompat.checkSelfPermission(context,
                permission) != PackageManager.PERMISSION_GRANTED
    

    fun checkPermission(context: Context, permission: String, completion: PermissionCheckCompletion) 
        // If permission is not granted
        if (shouldAskPermission(context, permission)) 
            //If permission denied previously
            if ((context as Activity).shouldShowRequestPermissionRationale(permission)) 
                completion(CheckPermissionResult.PermissionPreviouslyDenied)
             else 
                // Permission denied or first time requested
                if (PermissionUtil.isFirstTimeAskingPermission(context,
                                permission)) 
                    PermissionUtil.firstTimeAskingPermission(context,
                            permission,
                            false)
                    completion(CheckPermissionResult.PermissionAsk)
                 else 
                    // Handle the feature without permission or ask user to manually allow permission
                    completion(CheckPermissionResult.PermissionDisabled)
                
            
         else 
            completion(CheckPermissionResult.PermissionGranted)
        
    

实施

PermissionHandler.checkPermission(activity,
                    Manifest.permission.CAMERA)  result ->
                when (result) 
                    CheckPermissionResult.PermissionGranted -> 
                        // openCamera()
                    
                    CheckPermissionResult.PermissionDisabled -> 
                        // displayAlert(noPermissionAlert)
                    
                    CheckPermissionResult.PermissionAsk -> 
                        // requestCameraPermissions()
                    
                    CheckPermissionResult.PermissionPreviouslyDenied -> 
                        // displayAlert(permissionRequestAlert)
                    
                
            

【讨论】:

不要在 PermissionHandler.checkPermission() 中传递 Context,然后再将其转换为 Activity。上下文并不总是一个活动【参考方案7】:

检查此实现。对我来说效果很好。基本上,您在传递权限列表的 checkPermissions() 方法中检查权限。您在 onRequestPermissionsResult() 上检查权限请求的结果。当用户选择“不再询问”或不选择时,该实现让您解决这两种情况。在这个实现中,如果 se 选择“不再询问”,对话框有一个选项可以将他带到 App Settings Activity。

所有这些代码都在我的片段中。我认为创建一个专门的类来执行此操作会更好,例如 PermissionManager,但我不确定。

/**
     * responsible for checking if permissions are granted. In case permissions are not granted, the user will be requested and the method returns false. In case we have all permissions, the method return true.
     * The response of the request for the permissions is going to be handled in the onRequestPermissionsResult() method
     * @param permissions list of permissions to be checked if are granted onRequestPermissionsResult().
     * @param requestCode request code to identify this request in
     * @return true case we already have all permissions. false in case we had to prompt the user for it.
     */
    private boolean checkPermissions(List<String> permissions, int requestCode) 
        List<String> permissionsNotGranted = new ArrayList<>();
        for (String permission : permissions) 
            if (ContextCompat.checkSelfPermission(getActivity(), permission) != PackageManager.PERMISSION_GRANTED)
                permissionsNotGranted.add(permission);
        

        //If there is any permission we don't have (it's going to be in permissionsNotGranted List) , we need to request.
        if (!permissionsNotGranted.isEmpty()) 
            requestPermissions(permissionsNotGranted.toArray(new String[permissionsNotGranted.size()]), requestCode);
            return false;
        
        return true;
    

    /**
     * called after permissions are requested to the user. This is called always, either
     * has granted or not the permissions.
     * @param requestCode  int code used to identify the request made. Was passed as parameter in the
     *                     requestPermissions() call.
     * @param permissions  Array containing the permissions asked to the user.
     * @param grantResults Array containing the results of the permissions requested to the user.
     */
    @Override
    public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) 
        switch (requestCode) 
            case YOUR_REQUEST_CODE: 
                boolean anyPermissionDenied = false;
                boolean neverAskAgainSelected = false;
                // Check if any permission asked has been denied
                for (int i = 0; i < grantResults.length; i++) 
                    if (grantResults[i] != PackageManager.PERMISSION_GRANTED) 
                        anyPermissionDenied = true;
                        //check if user select "never ask again" when denying any permission
                        if (!shouldShowRequestPermissionRationale(permissions[i])) 
                            neverAskAgainSelected = true;
                        
                    
                
                if (!anyPermissionDenied) 
                    // All Permissions asked were granted! Yey!
                    // DO YOUR STUFF
                 else 
                    // the user has just denied one or all of the permissions
                    // use this message to explain why he needs to grant these permissions in order to proceed
                    String message = "";
                    DialogInterface.OnClickListener listener = null;
                    if (neverAskAgainSelected) 
                        //This message is displayed after the user has checked never ask again checkbox.
                        message = getString(R.string.permission_denied_never_ask_again_dialog_message);
                        listener = new DialogInterface.OnClickListener() 
                            @Override
                            public void onClick(DialogInterface dialog, int which) 
                                //this will be executed if User clicks OK button. This is gonna take the user to the App Settings
                                startAppSettingsConfigActivity();
                            
                        ;
                     else 
                        //This message is displayed while the user hasn't checked never ask again checkbox.
                        message = getString(R.string.permission_denied_dialog_message);
                    
                    new AlertDialog.Builder(getActivity(), R.style.AlertDialogTheme)
                            .setMessage(message)
                            .setPositiveButton(getString(R.string.label_Ok), listener)
                            .setNegativeButton(getString(R.string.label_cancel), null)
                            .create()
                            .show();
                
            
            break;
            default:
                super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        
    

    /**
     * start the App Settings Activity so that the user can change
     * settings related to the application such as permissions.
     */
    private void startAppSettingsConfigActivity() 
        final Intent i = new Intent();
        i.setAction(Settings.ACTION_APPLICATION_DETAILS_SETTINGS);
        i.addCategory(Intent.CATEGORY_DEFAULT);
        i.setData(Uri.parse("package:" + getActivity().getPackageName()));
        i.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        i.addFlags(Intent.FLAG_ACTIVITY_NO_HISTORY);
        i.addFlags(Intent.FLAG_ACTIVITY_EXCLUDE_FROM_RECENTS);
        getActivity().startActivity(i);
    

【讨论】:

【参考方案8】:

可能对某人有用:--

我注意到的是,如果我们在 onRequestPermissionsResult() 回调方法中检查 shouldShowRequestPermissionRationale() 标志,它只显示两种状态。

状态 1:-返回 true:-- 任何时候用户单击拒绝权限(包括第一次)。

状态 2:-返回 false :- 如果用户选择“不再询问”。

Link for detailed working example.

【讨论】:

它第一次返回 false。不正确 是的,这就是我提到的,如果你检查 onRequestPermissionsResult() 回调方法中的标志,它将只有两种状态,特别是在这个回调中。 不幸的是,shouldShowRequestPermissionRationale 总是返回 false - 无论用户是否拒绝了权限。【参考方案9】:

这样可以吗?

@Retention(RetentionPolicy.SOURCE)
@IntDef(GRANTED, DENIED, NEVER)
public @interface PermissionStatus 


public static final int GRANTED = 0;
public static final int DENIED = 1;
public static final int NEVER = 2;

@PermissionStatus
public static int getPermissionStatus(Activity activity, String permission) 
    if (ActivityCompat.shouldShowRequestPermissionRationale(activity, permission)) 
        return DENIED;
     else 
        if (ActivityCompat.checkSelfPermission(activity, permission) == PackageManager.PERMISSION_GRANTED) 
            return GRANTED;
         else 
            return NEVER;
        
    

【讨论】:

不幸的是,这段代码没有区分以前从未请求过权限和选中“不再请求”的情况。 你应该使用 this + 权限助手类的组合来检查权限是否被授予。【参考方案10】:

shouldShowRequestPermissionRationale 对于特殊权限,在用户拒绝后总是返回 TRUE ONLY没有复选框

我们对FALSE价值感兴趣

所以有 3 个案例丢失了 false 值:

1.以前没有这样的操作,现在用户决定同意或拒绝。

简单地定义一个偏好ASKED_PERMISSION_*,它现在不存在,并且在onRequestPermissionsResult开始时将是true,无论是同意还是拒绝

因此,虽然此偏好不存在,但没有理由检查shouldShowRequestPermissionRationale

2. 用户点击同意。

简单地做:

checkCallingOrSelfPermission(permission) == PackageManager.PERMISSION_GRANTED

哪个会返回 true 并且没有没有理由检查shouldShowRequestPermissionRationale

3.用户点击了拒绝复选框(第二次或更多次询问)

现在是使用shouldShowRequestPermissionRationale时间,这将返回FALSE

(偏好存在,我们没有权限)

【讨论】:

【参考方案11】:

此代码要求用户在运行时请求权限, 如果用户允许,它执行结果方法, 如果用户拒绝,它会再次询问用户拒绝的描述(它会再次询问说明), 但如果用户选择不再询问。 它处理不再询问,显示带有说明的打开设置选项。

public String storagePermissions = Manifest.permission.READ_EXTERNAL_STORAGE;   
private static final int REQUEST_ACCESS =101;  

@Override
protected void onCreate(Bundle savedInstanceState) 
    super.onCreate(savedInstanceState);

    setContentView(R.layout.activity_main);

    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) 
      if(checkSelfPermission(storagePermissions)== PackageManager.PERMISSION_GRANTED)
          result();    // result  is your block of code 
      else 
          requestPermissions(new String[]storagePermissions,REQUEST_ACCESS);
      

    
    else
        result();    //so if user is lower than api verison M, no permission is requested
     



 private void showMessageOKCancel(String message, DialogInterface.OnClickListener okListener) 
    new AlertDialog.Builder(MainActivity.this)
            .setMessage(message)
            .setTitle("Hi User..")
            .setPositiveButton("Ok", okListener)
            .setNegativeButton("Cancel", new DialogInterface.OnClickListener() 
                @Override
                public void onClick(DialogInterface dialog, int which)         //idea calling showMessage funtion again
                    Snackbar mySnackbar = Snackbar.make( findViewById(R.id.coordinatorlayout),"You Press Cancel.. ", Snackbar.LENGTH_INDEFINITE);
                    mySnackbar.setAction("Exit", new cancelButton());
                    mySnackbar.show();

                
            )
            .create()
            .show();



private void result()
          //your code


    @RequiresApi(api = Build.VERSION_CODES.M)
public class NeverAskAgain implements View.OnClickListener
    @Override
    public void onClick(View view)
    
        goToSettings();
    

@RequiresApi(api = Build.VERSION_CODES.M)
private void goToSettings() 
    Intent myAppSettings = new Intent(Settings.ACTION_APPLICATION_DETAILS_SETTINGS, Uri.parse("package:" + getPackageName()));
    finish();
    myAppSettings.addCategory(Intent.CATEGORY_DEFAULT);
    myAppSettings.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
    startActivityForResult(myAppSettings, REQUEST_APP_SETTINGS);

public class cancelButton implements View.OnClickListener
    @Override
    public void onClick(View view)
        Toast.makeText(MainActivity.this,"To use this app , you must grant storage permission",Toast.LENGTH_SHORT);
        finish();
    
    


 @Override
@RequiresApi(api = Build.VERSION_CODES.M)
public void onRequestPermissionsResult(int requestCode, @NonNull String permissions[], @NonNull int[] grantResults) 
    super.onRequestPermissionsResult(requestCode,permissions,grantResults);

    switch(requestCode) 
        case REQUEST_ACCESS:
                if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) 
                    // permission is granted
                    result();
                    break;
                
                else if (!shouldShowRequestPermissionRationale(permissions[0]))
                    showMessageOKCancel("You choose Never Ask Again,option",
                new DialogInterface.OnClickListener() 
                    @Override
                    public void onClick(DialogInterface dialog, int which) 
                        Snackbar mySnackbar = Snackbar.make(findViewById(R.id.coordinatorlayout), "Permission=>Storage=>On", Snackbar.LENGTH_INDEFINITE);
                        mySnackbar.setAction("Settings", new NeverAskAgain());
                        mySnackbar.show();
                    
                     );
                    break;
                
                else 
                    showMessageOKCancel("You Denid permission Request..",
                    new DialogInterface.OnClickListener() 
                        @Override
                        public void onClick(DialogInterface dialog, int which) 
                            requestPermissions(new String[]storagePermissions, REQUEST_ACCESS);
                        
                    );
                    break;
                
        

【讨论】:

【参考方案12】:
public void requestPermission(View view)
        if(ContextCompat.checkSelfPermission(this,Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED)
            if(ActivityCompat.shouldShowRequestPermissionRationale(MainActivity.this,Manifest.permission.ACCESS_FINE_LOCATION))

//The Alert Dialog before asking for the second time to help the user understand  why he needs to give permission.

                AlertDialog alert = new AlertDialog.Builder(this).setMessage("Without the permissions you cannot run the application")
                        .setCancelable(false)
                        .setPositiveButton("Okay, I understand", new DialogInterface.OnClickListener() 
                            @Override
                            public void onClick(DialogInterface dialog, int which) 
                                ActivityCompat.requestPermissions(MainActivity.this,
                                        new String[]Manifest.permission.ACCESS_FINE_LOCATION, REQUEST_FINE_LOCATION);
                            
                        ).setNegativeButton("No, Exit the App", new DialogInterface.OnClickListener() 
                    @Override
                    public void onClick(DialogInterface dialog, int which) 
                        System.exit(2);
                    
                ).create();
                alert.setTitle("ALERTY");
                alert.show();
//End of the alert Dialog
            
            else
                ActivityCompat.requestPermissions(MainActivity.this,
                        new String[]Manifest.permission.ACCESS_FINE_LOCATION, REQUEST_FINE_LOCATION);
            
        
        else 
            textView.setText("Permission Is Already Granted");
        
    
    /*
     The shouldShowRequestPermissionRationale() function returns true if the app has requested this permission
     previously and the user denied the request.If the user turned down the permission request in the past and chose
     the Don't ask again option, this method returns false.
      */
    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) 
        if(requestCode == REQUEST_FINE_LOCATION) 
            if (grantResults[0] == PackageManager.PERMISSION_GRANTED) 
                textView.setText("Hooray! on Request Permissions Granted");
            
            else
                //Since the user has chosen the don't ask again option,
                if(!ActivityCompat.shouldShowRequestPermissionRationale(MainActivity.this, Manifest.permission.ACCESS_FINE_LOCATION))

//Alert Dialog that will take user to settings where he can manually give the permissions
                    AlertDialog alert = new AlertDialog.Builder(this).setMessage("You have permanently disabled the permission ")
                            .setPositiveButton("Go to Settings", new DialogInterface.OnClickListener() 
                        @Override
                        public void onClick(DialogInterface dialog, int which) 
                             openSettings();
                        
                    ).setNegativeButton("Don't Go",null).setCancelable(false).create();
                  alert.setTitle("Give permission manually");
                  alert.show();
 // End of the Alert Dialog
                
                else
                    textView.setText("Permission has been denied the 1st time");
                
            
        
    

这是 openSettings 方法。

    public void openSettings()
        Intent intent = new Intent();

        Uri uri = Uri.fromParts("package",this.getPackageName(),null);
        intent.setAction(Settings.ACTION_APPLICATION_DETAILS_SETTINGS).setData(uri);
        startActivity(intent);
    

【讨论】:

我已经创建了意图,如果用户之前在 不再显示 按钮上进行了检查,他将被重定向到设置页面,他可以在其中授予权限手动。

以上是关于Android M 权限:对 shouldShowRequestPermissionRationale() 函数的用法感到困惑的主要内容,如果未能解决你的问题,请参考以下文章

Android M:以编程方式撤销权限

从服务 Android M 请求位置权限

对话框“不再询问”的 Android M 权限问题

Android M - 相机权限问题

低于 M 的 android 版本的 Android 运行时权限?

Android M(6.0) 权限爬坑之旅