Support for opening unsupported files with external apps

app/src/common/shared/org/mozilla/vrbrowser/ui/widgets/WindowWidget.java

@@ -5,7 +5,9 @@
 
 package org.mozilla.vrbrowser.ui.widgets;
 
+import android.content.ActivityNotFoundException;
 import android.content.Context;
+import android.content.Intent;
 import android.content.res.Configuration;
 import android.graphics.Canvas;
 import android.graphics.Matrix;
@@ -27,6 +29,7 @@
 import androidx.annotation.Nullable;
 import androidx.annotation.StringRes;
 import androidx.annotation.UiThread;
+import androidx.core.content.FileProvider;
 import androidx.lifecycle.ViewModelProvider;
 
 import org.mozilla.geckoview.AllowOrDeny;
@@ -62,6 +65,7 @@
 import org.mozilla.vrbrowser.utils.UrlUtils;
 import org.mozilla.vrbrowser.utils.ViewUtils;
 
+import java.io.File;
 import java.util.Arrays;
 import java.util.List;
 import java.util.concurrent.CopyOnWriteArrayList;
@@ -1419,9 +1423,11 @@ public void startDownload(@NonNull DownloadJob downloadJob, boolean showConfirmD
         Runnable download = () -> {
             if (showConfirmDialog) {
                 mWidgetManager.getFocusedWindow().showConfirmPrompt(
-                        "Download",
+                        getResources().getString(R.string.download_confirm_title),
                         downloadJob.getFilename(),
-                        new String[]{"Cancel", "Download"},
+                        new String[]{
+                                getResources().getString(R.string.download_confirm_cancel),
+                                getResources().getString(R.string.download_confirm_download)},
                         index -> mDownloadsManager.startDownload(downloadJob)
                 );
 
@@ -1509,10 +1515,37 @@ public void onFirstContentfulPaint(@NonNull GeckoSession session) {
 
     @Override
     public void onExternalResponse(@NonNull GeckoSession geckoSession, @NonNull GeckoSession.WebResponseInfo webResponseInfo) {
-        // We don't wat to trigger downloads of already downloaded files
+        // We don't want to trigger downloads of already downloaded files that we can't open
+        // so we let the system handle it.
         if (!UrlUtils.isFileUri(webResponseInfo.uri)) {
             DownloadJob job = DownloadJob.from(webResponseInfo);
             startDownload(job, true);
+
+        } else {
+            showConfirmPrompt(getResources().getString(R.string.download_open_file_unsupported_title),
+                    getResources().getString(R.string.download_open_file_unsupported_body),
+                    new String[]{
+                            getResources().getString(R.string.download_open_file_unsupported_cancel),
+                            getResources().getString(R.string.download_open_file_unsupported_open)
+                    }, index -> {
+                        if (index == PromptDialogWidget.POSITIVE) {
+                            Uri contentUri = FileProvider.getUriForFile(
+                                    getContext(),
+                                    getContext().getApplicationContext().getPackageName() + ".provider",
+                                    new File(webResponseInfo.uri.substring("file://".length())));
+                            Intent newIntent = new Intent(Intent.ACTION_VIEW);
+                            newIntent.setDataAndType(contentUri, webResponseInfo.contentType);
+                            newIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_GRANT_READ_URI_PERMISSION);
+                            try {
+                                getContext().startActivity(newIntent);
+                            } catch (ActivityNotFoundException ex) {
+                                showAlert(
+                                        getResources().getString(R.string.download_open_file_error_title),
+                                        getResources().getString(R.string.download_open_file_error_body),
+                                        null);
+                            }
+                        }
+                    });
         }
     }
 

app/src/main/AndroidManifest.xml

@@ -42,5 +42,14 @@
             android:process=":crash"
             android:permission="android.permission.BIND_JOB_SERVICE">
         </service>
+        <provider
+            android:name="androidx.core.content.FileProvider"
+            android:authorities="${applicationId}.provider"
+            android:exported="false"
+            android:grantUriPermissions="true">
+            <meta-data
+                android:name="android.support.FILE_PROVIDER_PATHS"
+                android:resource="@xml/downloads_provider"/>
+        </provider>
     </application>
 </manifest>

app/src/main/res/values/strings.xml

@@ -1545,4 +1545,40 @@ the Select` button. When clicked it closes all the previously selected tabs -->
 
     <!-- This string is displayed in the disable button of the quick Tracking Protection dialog, accessed from the Tracking Protection icon in the URL bar. -->
     <string name="tracking_dialog_button_disable">Disable</string>
+
+    <!-- This string is displayed in the title of the dialog displayed when the user tries to open an unsupported
+         file from the Downloads library panel. -->
+    <string name="download_open_file_unsupported_title">Unsupported File Type</string>
+
+    <!-- This string is displayed in the body of the dialog displayed when the user tries to open an unsupported
+         file from the Downloads library panel. -->
+    <string name="download_open_file_unsupported_body">The file cannot be opened, Do you want to open it with an external application?</string>
+
+    <!-- This string is displayed in the cancel button of the dialog displayed when the user tries to open an unsupported
+         file from the Downloads library panel. When clicked the dialog is closed.-->
+    <string name="download_open_file_unsupported_cancel">Cancel</string>
+
+    <!-- This string is displayed in the cancel button of the dialog displayed when the user tries to open an unsupported
+         file from the Downloads library panel. When clicked we hand over the file open to the system.-->
+    <string name="download_open_file_unsupported_open">Open</string>
+
+    <!-- This string is displayed in the title of the dialog displayed when we try to hand over the file open to
+         the system but the system can't handle it either. -->
+    <string name="download_open_file_error_title">Error</string>
+
+    <!-- This string is displayed in the body of the dialog displayed when we try to hand over the file open to
+         the system but the system can't handle it either. -->
+    <string name="download_open_file_error_body">No application found to handle this file type.</string>
+
+    <!-- This string is displayed in the title of the dialog displayed when a download has been requested
+         so the user can confirm if they want to actually download the file. -->
+    <string name="download_confirm_title">Would you like to download this file?</string>
+
+    <!-- This string is displayed in the "Cancel" button of the dialog displayed when a download has been requested
+         so the user can confirm if they want to actually download the file. If clicked the download is not started. -->
+    <string name="download_confirm_cancel">Cancel</string>
+
+    <!-- This string is displayed in the "Download" button of the dialog displayed when a download has been requested
+         so the user can confirm if they want to actually download the file. If clicked the download is queued. -->
+    <string name="download_confirm_download">Download</string>
 </resources>

app/src/main/res/xml/downloads_provider.xml

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<paths xmlns:android="http://schemas.android.com/apk/res/android">
+    <external-path name="external_files" path="."/>
+</paths>