Xamarin Android Web 视图文件选择器

Question

I wrote a hybrid app and I want to use file upload HTML (file and camera) page. I use the below code and it works well.

When the user clicks on FileUploader input, the native window opens (to choose between File or Camera) and everything works just fine.

My only problem is that, when user click out of the window , this one will be closed and after no more opened, maybe something to reinitialise or restart.

If someone has some ideas...

On MainActivity:

var chrome = new SmarterWebChromeClient((uploadMsg) =>
                        {
                            mUploadMessage = uploadMsg;

                            mCameraPhotoPath = null;

                            Intent takePictureIntent = new Intent(Android.Provider.MediaStore.ActionImageCapture);

                            //Create the File where the photo should go
                            File photoFile = null;
                            try
                            {
                                photoFile = createImageFile();
                                takePictureIntent.PutExtra("PhotoPath", mCameraPhotoPath);
                            }
                            catch (IOException ex)
                            {
                                // Error occurred while creating the File
                                writeEx(ex.ToString());
                            }

                            // Continue only if the File was successfully created
                            if (photoFile != null)
                            {
                                mCameraPhotoPath = "file:" + photoFile.AbsolutePath;
                                takePictureIntent.PutExtra(Android.Provider.MediaStore.ExtraOutput,
                                        Android.Net.Uri.FromFile(photoFile));
                            }
                            else
                            {
                                takePictureIntent = null;
                            }

                            Intent contentSelectionIntent = new Intent(Intent.ActionGetContent);
                            contentSelectionIntent.AddCategory(Intent.CategoryOpenable);
                            contentSelectionIntent.SetType("image/*");

                            Intent[] intentArray;
                            if (takePictureIntent != null)
                            {
                                intentArray = new Intent[] { takePictureIntent };
                            }
                            else
                            {
                                intentArray = new Intent[0];
                            }

                            Intent chooserIntent = new Intent(Intent.ActionChooser);
                            chooserIntent.PutExtra(Intent.ExtraIntent, contentSelectionIntent);
                            chooserIntent.PutExtra(Intent.ExtraTitle, "Choisir une photo");
                            chooserIntent.PutExtra(Intent.ExtraInitialIntents, intentArray);

                            StartActivityForResult(chooserIntent, MainActivity.FILECHOOSER_RESULTCODE);

                        });


                        mWebView.SetWebViewClient(new MyWebViewClient());

                        mWebView.SetWebChromeClient(chrome);

...

  protected override void OnActivityResult(int requestCode, Result resultCode, Intent intent)
            {
                if (requestCode == FILECHOOSER_RESULTCODE)
                {
                    if (null == mUploadMessage)
                        return;

                    // Check that the response is a good one
                    if (resultCode == Result.Ok)
                    {
                        Android.Net.Uri[] results = null;
                        if (intent == null)
                        {
                            // If there is not data, then we may have taken a photo
                            if (mCameraPhotoPath != null)
                            {
                                results = new Android.Net.Uri[] { Android.Net.Uri.Parse(mCameraPhotoPath) };
                            }
                            else
                            {

                            }
                        }
                        else
                        {
                            if (intent.DataString != null)
                            {
                                results = new Android.Net.Uri[] { Android.Net.Uri.Parse(intent.DataString) };
                            }
                        }

                        mUploadMessage.OnReceiveValue(results);
                        mUploadMessage = null;
                    }
                }
            }

And my WebChromeClient Class :

 partial class SmarterWebChromeClient : WebChromeClient
        {
            Action<IValueCallback> callback;

            public SmarterWebChromeClient(Action<IValueCallback> callback)
            {
                this.callback = callback;
            }

            public override bool OnShowFileChooser(WebView webView, IValueCallback filePathCallback, FileChooserParams fileChooserParams)
            {
                callback(filePathCallback);
                return true;
            }
        }

Answer 1

I solve your problem like below code Put an else part for result NOT OK

// Check that the response is a good one
if (resultCode == Result.Ok)
{
   //...
}
else
{
   mUploadMessage.OnReceiveValue(null);
   mUploadMessage = null;
}