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

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.

其他回答

一个有用的函数来确定任意权限是否被阻止请求(在Kotlin中):

private fun isPermissionBlockedFromAsking(activity: Activity, permission: String): Boolean {
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
        return ContextCompat.checkSelfPermission(activity, permission) != PackageManager.PERMISSION_GRANTED
            && !activity.shouldShowRequestPermissionRationale(permission)
            && PreferenceManager.getDefaultSharedPreferences(activity).getBoolean(permission, false)
    }
    return false
}

当你第一次请求一个权限时,需要设置一个共享首选项布尔值为true,其中包含你想要的权限名称(例如android.Manifest.permission.READ_PHONE_STATE)。


解释:

Build.VERSION。SDK_INT >= Build.VERSION_CODES。因为有些代码只能在API级别23+上运行。

ContextCompat。checkSelfPermission(activity, permission) != PackageManager。permission_granting检查我们还没有权限。

activity.shouldShowRequestPermissionRationale(permission)来检查用户是否再次拒绝了应用程序的请求。由于这个函数的特性,还需要下面这行代码。

PreferenceManager.getDefaultSharedPreferences(活动)。getBoolean(permission, false)用于区分“Never asked”和“Never ask again”状态(以及在第一次权限请求时将值设置为true),因为前一行不会返回此信息。

您可以使用if (ActivityCompat。shouldShowRequestPermissionRationale(this, Manifest.permission.CAMERA)方法来检测never ask是否被检查。

更多参考:检查这个

检查是否使用了多个权限:

  if (ActivityCompat.shouldShowRequestPermissionRationale(this, Manifest.permission.CAMERA)
                                || ActivityCompat.shouldShowRequestPermissionRationale(this, Manifest.permission.WRITE_EXTERNAL_STORAGE)
                                || ActivityCompat.shouldShowRequestPermissionRationale(this, Manifest.permission.ACCESS_FINE_LOCATION)
                                || ActivityCompat.shouldShowRequestPermissionRationale(this, Manifest.permission.RECORD_AUDIO)) {
                            showDialogOK("Service Permissions are required for this app",
                                    new DialogInterface.OnClickListener() {
                                        @Override
                                        public void onClick(DialogInterface dialog, int which) {
                                            switch (which) {
                                                case DialogInterface.BUTTON_POSITIVE:
                                                    checkAndRequestPermissions();
                                                    break;
                                                case DialogInterface.BUTTON_NEGATIVE:
                                                    // proceed with logic by disabling the related features or quit the app.
                                                    finish();
                                                    break;
                                            }
                                        }
                                    });
                        }
                        //permission is denied (and never ask again is  checked)
                        //shouldShowRequestPermissionRationale will return false
                        else {
                            explain("You need to give some mandatory permissions to continue. Do you want to go to app settings?");
                            //                            //proceed with logic by disabling the related features or quit the app.
                        }

解释()方法

private void explain(String msg){
        final android.support.v7.app.AlertDialog.Builder dialog = new android.support.v7.app.AlertDialog.Builder(this);
        dialog.setMessage(msg)
                .setPositiveButton("Yes", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface paramDialogInterface, int paramInt) {
                        //  permissionsclass.requestPermission(type,code);
                        startActivity(new Intent(android.provider.Settings.ACTION_APPLICATION_DETAILS_SETTINGS, Uri.parse("package:com.exampledemo.parsaniahardik.marshmallowpermission")));
                    }
                })
                .setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface paramDialogInterface, int paramInt) {
                        finish();
                    }
                });
        dialog.show();
    }

上面的代码还将显示对话框,这将重定向到用户的应用程序设置屏幕,在那里他可以给予权限,如果选中了“永不再问”按钮。

我必须实现相机的动态权限。有三种可能的情况:允许2。否认,3。别再问了。

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

    for (String permission : permissions) {
        if (ActivityCompat.shouldShowRequestPermissionRationale(getActivity(), permission)) {
            //denied
            Log.e("denied", permission);
        } else {
            if (ActivityCompat.checkSelfPermission(getActivity(), permission) == PackageManager.PERMISSION_GRANTED) {
                //allowed
                Log.e("allowed", permission);
            } else {
                //set to never ask again
                Log.e("set to never ask again", permission);
                //do something here.
            }
        }
    }
    if (requestCode != MaterialBarcodeScanner.RC_HANDLE_CAMERA_PERM) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        return;
    }
    if (grantResults.length != 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
        mScannerView.setResultHandler(this);
        mScannerView.startCamera(mCameraId);
        mScannerView.setFlash(mFlash);
        mScannerView.setAutoFocus(mAutoFocus);
        return;
    } else {
        //set to never ask again
        Log.e("set to never ask again", permissions[0]);
    }
    DialogInterface.OnClickListener listener = new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int id) {
            dialog.cancel();
        }
    };
    AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
    builder.setTitle("Error")
            .setMessage(R.string.no_camera_permission)
            .setPositiveButton(android.R.string.ok, listener)
            .show();


}

private void insertDummyContactWrapper() {
        int hasWriteContactsPermission = checkSelfPermission(Manifest.permission.CAMERA);
        if (hasWriteContactsPermission != PackageManager.PERMISSION_GRANTED) {
            requestPermissions(new String[]{Manifest.permission.CAMERA},
                    REQUEST_CODE_ASK_PERMISSIONS);
            return;
        }
        mScannerView.setResultHandler(this);
        mScannerView.startCamera(mCameraId);
        mScannerView.setFlash(mFlash);
        mScannerView.setAutoFocus(mAutoFocus);
    }

private int checkSelfPermission(String camera) {
    if (ContextCompat.checkSelfPermission(getActivity(), Manifest.permission.CAMERA)
            != PackageManager.PERMISSION_GRANTED) {
        return REQUEST_CODE_ASK_PERMISSIONS;
    } else {
        return REQUEST_NOT_CODE_ASK_PERMISSIONS;
    }
}

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();
            }
        }
    }

}

shouldShowRequestPermissionRationale()方法可以用来检查用户是否选择了“never asked again”选项并拒绝了权限。 有很多代码示例,所以我宁愿解释如何将它用于这样的目的,因为我认为它的名称和实现使它比实际情况更加复杂。

正如在运行时请求权限中解释的那样,如果选项“never ask again”可见,该方法返回true,否则返回false;因此,它在第一次显示对话框时返回false,然后从第二次开始返回true,只有当用户拒绝选择该选项的权限时,它才会再次返回false。

要检测这种情况,您可以检测序列false-true-false,或者(更简单)您可以使用一个标记来跟踪对话框显示的初始时间。在此之后,该方法返回true或false,其中false将允许您检测何时选择该选项。