Android 6.0 运行时权限+意图过滤器

Question

我需要访问我的意图过滤器中的存储，以在 Android 6.0 应用程序中获取 pdf 文件或图像。

[IntentFilter(new[] { Intent.ActionOpenDocument, Intent.ActionView }, Categories = new[] { Intent.CategoryDefault, Intent.CategoryBrowsable }, DataMimeType = "application/pdf")]
[IntentFilter(new[] { Intent.ActionOpenDocument, Intent.ActionView }, Categories = new[] { Intent.CategoryDefault, Intent.CategoryBrowsable }, DataMimeType = "image/jpeg")]
[IntentFilter(new[] { Intent.ActionOpenDocument, Intent.ActionView }, Categories = new[] { Intent.CategoryDefault, Intent.CategoryBrowsable }, DataMimeType = "image/png")]

但是，它需要用户授予应用的存储权限。

问题是这种情况是否有任何适当的 POC，我可以阻止意图、显示警报，然后根据授予/撤销权限完成我的意图？

目前我假设我只能显示一些没有权限的 toast，并温和地要求用户进入应用程序并手动启用权限（通过一些自定义应用程序设置或其他方式）。

Answer 1

   private static final int REQUEST_RUNTIME_PERMISSION = 1;

     void checkPremission() {
            //Desired permission you want
            final String permission = Manifest.permission.CAMERA;
                // if in fragment use getActivity()

            if (ContextCompat.checkSelfPermission(ActivityName.this, permission)
                    != PackageManager.PERMISSION_GRANTED) {
                if (ActivityCompat.shouldShowRequestPermissionRationale(ActivityName.this, permission)) {

                } else {
                    ActivityCompat.requestPermissions(ActivityName.this, new String[]{permission}, REQUEST_CAMERA_PERMISSION);
                }
            } else {
                // you have permission go ahead

            }
        }

        @Override
        public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
            switch (requestCode) {
                case REQUEST_RUNTIME_PERMISSION:
                    final int numOfRequest = grantResults.length;
                    final boolean isGranted = numOfRequest == 1
                            && PackageManager.PERMISSION_GRANTED == grantResults[numOfRequest - 1];
                    if (isGranted) {
                        // you have permission go ahead
                    }else{
                        // you dont have permission show toast
                    }
                    break;
                default:
                    super.onRequestPermissionsResult(requestCode, permissions, grantResults);
            }
        }

Answer 2

private void requestPermission() {

    int writePermission = ContextCompat.checkSelfPermission(
            MyActivity.this,
            Manifest.permission.WRITE_EXTERNAL_STORAGE);
    if (writePermission != PackageManager.PERMISSION_GRANTED) {

        // Should we show an explanation?
        // if (ActivityCompat.shouldShowRequestPermissionRationale(
        // MyActivity.this,
        // Manifest.permission.WRITE_EXTERNAL_STORAGE)) {
        //
        // // Show an expanation to the user *asynchronously* -- don't
        // // block
        // // this thread waiting for the user's response! After the user
        // // sees the explanation, try again to request the permission.
        //
        // } else {

        // No explanation needed, we can request the permission.

        ActivityCompat
                .requestPermissions(
                        MyActivity.this,
                        new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},
                        MY_PERMISSIONS_WRITE_TO_EXTERNAL_STORAGE);

        // MY_PERMISSIONS_WRITE_TO_EXTERNAL_STORAGE is an
        // app-defined int constant. The callback method gets the
        // result of the request.
        // }
    }
}

@Override
public void onRequestPermissionsResult(int requestCode,
                                       String permissions[], int[] grantResults) {
    switch (requestCode) {
        case MY_PERMISSIONS_WRITE_TO_EXTERNAL_STORAGE: {
            // If request is cancelled, the result arrays are empty.
            if (grantResults.length > 0
                    && grantResults[0] == PackageManager.PERMISSION_GRANTED) {

                // permission was granted, yay! Do the
                // permission-related task you need to do.

            } else {

                MyActivity.this.finish();
                // permission denied, boo! Disable the
                // functionality that depends on this permission.
            }
            return;
        }

        // other 'case' lines to check for other
        // permissions this app might request
    }
}

我在这里使用了 WRITE_EXTERNAL_STORAGE 权限，因为它授予了读写权限。

在您需要的地方调用requestPermission() 方法，然后从您的设备中获取pdf 或图像。

希望这会有所帮助。

Answer 3

感谢您的回答，但也许我忘了在问题中提及它，但我标记了它 - 我正在寻找 Xamarin 技术的答案。

时间过去了，但在那之前，我们终于找到了解决办法。更多的是这样的代码：

        private bool HandlAndroidRuntimePermissions(Intent intent)
        {
            const int toastTimeout = 5;
            const string permissionName = "File Drop";

            try
            {
                PermissionStatus status;
                using (var checkPermissionStatusAsync = CrossPermissions.Current.CheckPermissionStatusAsync(Permission.Storage))
                {
                    status = checkPermissionStatusAsync.Result;
                }

                if (status != PermissionStatus.Granted)
                {
                    using (var shouldShowRequestPermissionRationaleAsync = CrossPermissions.Current.ShouldShowRequestPermissionRationaleAsync(Permission.Storage))
                    {
                        if (shouldShowRequestPermissionRationaleAsync.Result)
                        {
                            UserDialogs.Instance.Toast(
                                string.Format(Core.Resources.Resource.DocumentPickerModalViewModel_AndroidPermissionWrapper_RequestPermissionRationale, Permission.Storage, permissionName),
                                TimeSpan.FromSeconds (toastTimeout));
                        }
                    }

                    using (var requestPermissionsAsync = CrossPermissions.Current.RequestPermissionsAsync(Permission.Storage))
                    {
                        requestPermissionsAsync.ContinueWith(task =>
                        {
                            var permissionStatuses = task.Result;
                            status = permissionStatuses[Permission.Storage];
                            if (status == PermissionStatus.Granted)
                            {
                                CopyDocumentFromDeviceToMyLibrary(intent);
                            }
                            UserDialogs.Instance.Toast(string.Format(Core.Resources.Resource.DocumentPickerModalViewModel_AndroidPermissionWrapper_PermissionNotGrant, Permission.Storage, permissionName),
                                TimeSpan.FromSeconds (toastTimeout));
                        });
                    }
                    return true;
                }
            }
            catch (Exception)
            {
                UserDialogs.Instance.Toast(string.Format(Core.Resources.Resource.DocumentPickerModalViewModel_AndroidPermissionWrapper_ErrorOccured, Permission.Storage),
                    TimeSpan.FromSeconds (toastTimeout));
                return true;
            }

            return false;
        }