根据这个:http://developer.android.com/preview/features/runtime-permissions.html#coding一个应用程序可以检查运行时权限和请求权限,如果它还没有被授予。弹出如下对话框:

如果用户拒绝一个重要的权限,在我看来,应用程序应该显示一个解释为什么需要权限和什么影响拒绝。该对话框有两个选项:

重试(再次请求许可) 拒绝(应用程序将工作没有该许可)。

但是,如果用户选中“Never ask again”,则不应该显示带有解释的第二个对话框,特别是如果用户之前已经拒绝了一次。 现在的问题是:我的应用程序如何知道用户是否选中了Never ask again?IMO onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults)没有给我这个信息。

第二个问题是:谷歌是否计划在权限对话框中包含一个自定义消息,以解释为什么应用程序需要权限?这样就不会出现第二个对话框,这肯定会带来更好的用户体验。


当前回答

你可以使用

shouldShowRequestPermissionRationale()

内部

onRequestPermissionsResult()

请看下面的例子:

当用户点击按钮时检查是否有权限:

@Override
public void onClick(View v) {
    if (v.getId() == R.id.appCompatBtn_changeProfileCoverPhoto) {
        if (Build.VERSION.SDK_INT < 23) { // API < 23 don't need to ask permission
            navigateTo(MainActivity.class); // Navigate to activity to change photos
        } else {
            if (ContextCompat.checkSelfPermission(SettingsActivity.this, Manifest.permission.WRITE_EXTERNAL_STORAGE)
                    != PackageManager.PERMISSION_GRANTED) {
                // Permission is not granted yet. Ask for permission...
                requestWriteExternalPermission();
            } else {
                // Permission is already granted, good to go :)
                navigateTo(MainActivity.class);
            }
        } 
    }
}

当用户回答权限对话框时,我们将进入onRequestPermissionResult:

@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
    super.onRequestPermissionsResult(requestCode, permissions, grantResults);

    if (requestCode == WRITE_EXTERNAL_PERMISSION_REQUEST_CODE) {
        // Case 1. Permission is granted.  
        if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {  
            if (ContextCompat.checkSelfPermission(SettingsActivity.this, Manifest.permission.WRITE_EXTERNAL_STORAGE)
                    == PackageManager.PERMISSION_GRANTED) {
                // Before navigating, I still check one more time the permission for good practice.
                navigateTo(MainActivity.class);
            }
        } else { // Case 2. Permission was refused
            if (ActivityCompat.shouldShowRequestPermissionRationale(this, Manifest.permission.WRITE_EXTERNAL_STORAGE)) {
                // Case 2.1. shouldShowRequest... returns true because the
                // permission was denied before. If it is the first time the app is running we will 
                // end up in this part of the code. Because he need to deny at least once to get 
                // to onRequestPermissionsResult. 
                Snackbar snackbar = Snackbar.make(findViewById(R.id.relLayout_container), R.string.you_must_verify_permissions_to_send_media, Snackbar.LENGTH_LONG);
                snackbar.setAction("VERIFY", new View.OnClickListener() {
                    @Override
                    public void onClick(View v) {
                        ActivityCompat.requestPermissions(SettingsActivity.this
                                , new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}
                                , WRITE_EXTERNAL_PERMISSION_REQUEST_CODE);
                    }
                });
                snackbar.show();
            } else {
                // Case 2.2. Permission was already denied and the user checked "Never ask again". 
                // Navigate user to settings if he choose to allow this time.
                AlertDialog.Builder builder = new AlertDialog.Builder(this);
                builder.setMessage(R.string.instructions_to_turn_on_storage_permission)
                        .setPositiveButton(getString(R.string.settings), new DialogInterface.OnClickListener() {
                            @Override
                            public void onClick(DialogInterface dialog, int which) {
                                Intent settingsIntent = new Intent(Settings.ACTION_APPLICATION_DETAILS_SETTINGS);
                                Uri uri = Uri.fromParts("package", getPackageName(), null);
                                settingsIntent.setData(uri);
                                startActivityForResult(settingsIntent, 7);
                            }
                        })
                        .setNegativeButton(getString(R.string.not_now), null);
                Dialog dialog = builder.create();
                dialog.show();
            }
        }
    }

}

其他回答

扩展上面mVck的答案,下面的逻辑确定是否“Never ask again”已经为给定的权限请求进行了检查:

bool bStorage = grantResults[0] == Permission.Granted;
bool bNeverAskForStorage =
    !bStorage && (
        _bStorageRationaleBefore == true  && _bStorageRationaleAfter == false ||
        _bStorageRationaleBefore == false && _bStorageRationaleAfter == false
    );

摘自下面(完整的例子见这个答案)

private bool _bStorageRationaleBefore;
private bool _bStorageRationaleAfter;        
private const int ANDROID_PERMISSION_REQUEST_CODE__SDCARD = 2;
//private const int ANDROID_PERMISSION_REQUEST_CODE__CAMERA = 1;
private const int ANDROID_PERMISSION_REQUEST_CODE__NONE = 0;

public override void OnRequestPermissionsResult(int requestCode, string[] permissions, [GeneratedEnum] Permission[] grantResults)
{
    base.OnRequestPermissionsResult(requestCode, permissions, grantResults);

    switch (requestCode)
    {
        case ANDROID_PERMISSION_REQUEST_CODE__SDCARD:               
            _bStorageRationaleAfter = ShouldShowRequestPermissionRationale(Android.Manifest.Permission.WriteExternalStorage);
            bool bStorage = grantResults[0] == Permission.Granted;
            bool bNeverAskForStorage =
                !bStorage && (
                    _bStorageRationaleBefore == true  && _bStorageRationaleAfter == false ||
                    _bStorageRationaleBefore == false && _bStorageRationaleAfter == false
                );      
            break;                
    }
}

private List<string> GetRequiredPermissions(out int requestCode)
{
    // Android v6 requires explicit permission granting from user at runtime for security reasons            
    requestCode = ANDROID_PERMISSION_REQUEST_CODE__NONE; // 0
    List<string> requiredPermissions = new List<string>();

    _bStorageRationaleBefore = ShouldShowRequestPermissionRationale(Android.Manifest.Permission.WriteExternalStorage);
    Permission writeExternalStoragePerm = ApplicationContext.CheckSelfPermission(Android.Manifest.Permission.WriteExternalStorage);
    //if(extStoragePerm == Permission.Denied)
    if (writeExternalStoragePerm != Permission.Granted)
    {
        requestCode |= ANDROID_PERMISSION_REQUEST_CODE__SDCARD;
        requiredPermissions.Add(Android.Manifest.Permission.WriteExternalStorage);
    }

    return requiredPermissions;
}

protected override void OnCreate(Bundle savedInstanceState)
{
    base.OnCreate(savedInstanceState);

        // Android v6 requires explicit permission granting from user at runtime for security reasons
        int requestCode;
        List<string> requiredPermissions = GetRequiredPermissions(out requestCode);
        if (requiredPermissions != null && requiredPermissions.Count > 0)
        {
            if (requestCode >= ANDROID_PERMISSION_REQUEST_CODE__SDCARD)                    
            {
                _savedInstanceState = savedInstanceState;
                RequestPermissions(requiredPermissions.ToArray(), requestCode);
                return;
            }
        }
    }            

    OnCreate2(savedInstanceState);
}

开发者预览2对应用程序请求权限的方式进行了一些更改(参见http://developer.android.com/preview/support.html#preview2-notes)。

第一个对话框现在看起来像这样:

没有“永不再次显示”复选框(不像开发人员预览1)。如果用户拒绝权限,如果权限是必不可少的应用程序,它可以显示另一个对话框来解释应用程序请求该权限的原因,例如:

如果用户再次拒绝,应用程序应该关闭(如果它绝对需要该权限)或继续运行有限的功能。如果用户重新考虑(并选择重试),则再次请求权限。这次的提示符是这样的:

第二次显示“永不再问”复选框。如果用户再次拒绝并且勾选复选框,就不会再发生任何事情。 是否勾选复选框可以通过使用Activity.shouldShowRequestPermissionRationale(String)来确定,例如:

if (shouldShowRequestPermissionRationale(Manifest.permission.WRITE_CONTACTS)) {...

这就是Android文档所说的(https://developer.android.com/training/permissions/requesting.html):

To help find the situations where you need to provide extra explanation, the system provides the Activity.shouldShowRequestPermissionRationale(String) method. This method returns true if the app has requested this permission previously and the user denied the request. That indicates that you should probably explain to the user why you need the permission. If the user turned down the permission request in the past and chose the Don't ask again option in the permission request system dialog, this method returns false. The method also returns false if the device policy prohibits the app from having that permission.

要知道用户是否拒绝了“never ask again”,你可以再次检查你的onRequestPermissionsResult中的shouldShowRequestPermissionRationale方法,当用户没有授予权限时。

@Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
    if (requestCode == REQUEST_PERMISSION) {
        // for each permission check if the user granted/denied them
        // you may want to group the rationale in a single dialog,
        // this is just an example
        for (int i = 0, len = permissions.length; i < len; i++) {
            String permission = permissions[i];
            if (grantResults[i] == PackageManager.PERMISSION_DENIED) {
            // user rejected the permission
                boolean showRationale = shouldShowRequestPermissionRationale( permission );
                if (! showRationale) {
                    // user also CHECKED "never ask again"
                    // you can either enable some fall back,
                    // disable features of your app
                    // or open another dialog explaining
                    // again the permission and directing to
                    // the app setting
                } else if (Manifest.permission.WRITE_CONTACTS.equals(permission)) {
                    showRationale(permission, R.string.permission_denied_contacts);
                    // user did NOT check "never ask again"
                    // this is a good place to explain the user
                    // why you need the permission and ask if he wants
                    // to accept it (the rationale)
                } else if ( /* possibly check more permissions...*/ ) {
                }
            }
        }
    }
}

你可以用下面的代码打开你的应用程序设置:

Intent intent = new Intent(Settings.ACTION_APPLICATION_DETAILS_SETTINGS);
Uri uri = Uri.fromParts("package", getPackageName(), null);
intent.setData(uri);
startActivityForResult(intent, REQUEST_PERMISSION_SETTING);

无法将用户直接发送到授权页面。

你可以听漂亮。

侦听器

interface PermissionListener {
    fun onNeedPermission()
    fun onPermissionPreviouslyDenied(numberDenyPermission: Int)
    fun onPermissionDisabledPermanently(numberDenyPermission: Int)
    fun onPermissionGranted()
}

MainClass的权限

class PermissionUtil {

    private val PREFS_FILENAME = "permission"
    private val TAG = "PermissionUtil"

    private fun shouldAskPermission(context: Context, permission: String): Boolean {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            val permissionResult = ActivityCompat.checkSelfPermission(context, permission)
            if (permissionResult != PackageManager.PERMISSION_GRANTED) {
                return true
            }
        }
        return false
    }

    fun checkPermission(context: Context, permission: String, listener: PermissionListener) {

        Log.i(TAG, "CheckPermission for $permission")

        if (shouldAskPermission(context, permission)) {

            // Load history permission
            val sharedPreference = context.getSharedPreferences(PREFS_FILENAME, 0)
            val numberShowPermissionDialog = sharedPreference.getInt(permission, 0)

            if (numberShowPermissionDialog == 0) {

                (context as? Activity)?.let {
                    if (ActivityCompat.shouldShowRequestPermissionRationale(it, permission)) {
                        Log.e(TAG, "User has denied permission but not permanently")
                        listener.onPermissionPreviouslyDenied(numberShowPermissionDialog)
                    } else {
                        Log.e(TAG, "Permission denied permanently.")
                        listener.onPermissionDisabledPermanently(numberShowPermissionDialog)
                    }
                } ?: kotlin.run {
                    listener.onNeedPermission()
                }

            } else {
                // Is FirstTime
                listener.onNeedPermission()
            }


            // Save history permission
            sharedPreference.edit().putInt(permission, numberShowPermissionDialog + 1).apply()


        } else {
            listener.onPermissionGranted()
        }

    }
}

以这种方式使用

      PermissionUtil().checkPermission(this, Manifest.permission.ACCESS_FINE_LOCATION,
                object : PermissionListener {
                    override fun onNeedPermission() {
                        log("---------------------->onNeedPermission")

//                            ActivityCompat.requestPermissions(this@SplashActivity,
//                                    Array(1) { Manifest.permission.ACCESS_FINE_LOCATION },
//                                    118)

                    }

                    override fun onPermissionPreviouslyDenied(numberDenyPermission: Int) {
                        log("---------------------->onPermissionPreviouslyDenied")
                    }

                    override fun onPermissionDisabledPermanently(numberDenyPermission: Int) {
                        log("---------------------->onPermissionDisabled")
                    }

                    override fun onPermissionGranted() {
                        log("---------------------->onPermissionGranted")
                    }

                })

在activity或fragmnet中覆盖onRequestPermissionsResult

override fun onRequestPermissionsResult(requestCode: Int, permissions: Array<out String>, grantResults: IntArray) {
 if (requestCode == 118) {
        if (permissions[0] == Manifest.permission.ACCESS_FINE_LOCATION && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
            getLastLocationInMap()
        }
        }
    }

我还想知道用户是否选择了“never ask again”。我已经实现了一个“几乎解决方案”与一个丑陋的旗帜,但在我告诉你如何,我将告诉你我的动机:

I would like to offer the permission referring functionality initially. If the user uses it and has no rights, he/she gets the either the 1th dialog from above or both the 2nd and 3rd. When the user has chosen 'Never ask again' I would like to disable the functionality and to display it differently. - My action is triggered by a spinner text entry, I would also like to add '(Permission revoked)' to the label text displayed. This shows to the user: 'There is functionality but I cannot use it, due to my permission settings.' However, this does not seem to be possible, as I cannot check whether or not 'Never ask again' has been chosen.

I came to a solution I can live with by having my functionality always enabled with an active permission check. I am showing a Toast message in onRequestPermissionsResult() in case of a negative response but only if I have not shown my custom rationale popup. So if the user has chosen 'Never ask again' he gets a toast message only. If the user is reluctant to chose 'never ask again' he gets only the custom rationale and the permission request popup by the operation system but not toast, as three notifications in a row would be too much pain.

shouldShowRequestPermissionRationale根据之前权限请求中的用户首选项返回true或false。

如果用户只是拒绝权限(不是永远)shouldShowRequestPermissionRationale将返回true。如果永远拒绝许可,则返回false。窍门是即使用户允许了权限shouldShowRequestPermissionRationale也会返回false。

因此,我们可以结合这两个条件来得到永不再问的选择与否。

因此,如果用户不允许权限,并且shouldShowRequestPermissionRationale返回false,那么这意味着用户选择永远不会再次请求权限。

https://stackoverflow.com/a/58114769/5151336