feature/android 0014a10b242: Correctly export file:// URIs on Android

[Po Lu]

branch: feature/android
commit 0014a10b242bac62b0ba913a5ee4da4cfbe07f41
Author: Po Lu <luangruo@yahoo.com>
Commit: Po Lu <luangruo@yahoo.com>

    Correctly export file:// URIs on Android
    
    * java/org/gnu/emacs/EmacsService.java (browseUrl): If uri's
    scheme is `file', rewrite it into a content URI.
---
 java/org/gnu/emacs/EmacsService.java | 28 ++++++++++++++++++++++++++--
 1 file changed, 26 insertions(+), 2 deletions(-)

diff --git a/java/org/gnu/emacs/EmacsService.java 
b/java/org/gnu/emacs/EmacsService.java
index 2f35933a7d1..dde60e1c5af 100644
--- a/java/org/gnu/emacs/EmacsService.java
+++ b/java/org/gnu/emacs/EmacsService.java
@@ -62,6 +62,8 @@ import android.os.Vibrator;
 import android.os.VibratorManager;
 import android.os.VibrationEffect;
 
+import android.provider.DocumentsContract;
+
 import android.util.Log;
 import android.util.DisplayMetrics;
 
@@ -546,11 +548,33 @@ public final class EmacsService extends Service
   browseUrl (String url)
   {
     Intent intent;
+    Uri uri;
 
     try
       {
-       intent = new Intent (Intent.ACTION_VIEW, Uri.parse (url));
-       intent.setFlags (Intent.FLAG_ACTIVITY_NEW_TASK);
+       /* Parse the URI.  */
+       uri = Uri.parse (url);
+
+       if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT)
+         {
+           /* On Android 4.4 and later, check if URI is actually a
+              file name.  If so, rewrite it into a content provider
+              URI, so that it can be accessed by other programs.  */
+
+           if (uri.getScheme ().equals ("file")
+               && uri.getPath () != null)
+             uri
+               = DocumentsContract.buildDocumentUri ("org.gnu.emacs",
+                                                     uri.getPath ());
+         }
+
+       Log.d (TAG, ("browseUri: browsing " + url
+                    + " --> " + uri.getPath ()
+                    + " --> " + uri));
+
+       intent = new Intent (Intent.ACTION_VIEW, uri);
+       intent.setFlags (Intent.FLAG_ACTIVITY_NEW_TASK
+                        | Intent.FLAG_GRANT_READ_URI_PERMISSION);
        startActivity (intent);
       }
     catch (Exception e)