Enable preview for image drafts

Closes #4863

src/org/thoughtcrime/securesms/MediaPreviewActivity.java

@@ -138,7 +138,7 @@ public class MediaPreviewActivity extends PassphraseRequiredActionBarActivity im
 
     mediaUri     = getIntent().getData();
     mediaType    = getIntent().getType();
-    date         = getIntent().getLongExtra(DATE_EXTRA, -1);
+    date         = getIntent().getLongExtra(DATE_EXTRA, System.currentTimeMillis());
 
     if (recipientId > -1) {
       recipient = RecipientFactory.getRecipientForId(this, recipientId, true);

src/org/thoughtcrime/securesms/mms/AttachmentManager.java

@@ -32,13 +32,13 @@ import android.util.Log;
 import android.view.View;
 import android.widget.Toast;
 
+import org.thoughtcrime.securesms.MediaPreviewActivity;
 import org.thoughtcrime.securesms.R;
 import org.thoughtcrime.securesms.components.AudioView;
 import org.thoughtcrime.securesms.components.RemovableMediaView;
 import org.thoughtcrime.securesms.components.ThumbnailView;
 import org.thoughtcrime.securesms.crypto.MasterSecret;
 import org.thoughtcrime.securesms.providers.PersistentBlobProvider;
-import org.thoughtcrime.securesms.recipients.Recipients;
 import org.thoughtcrime.securesms.util.MediaUtil;
 import org.thoughtcrime.securesms.util.ViewUtil;
 import org.thoughtcrime.securesms.util.concurrent.ListenableFuture.Listener;
@@ -76,6 +76,7 @@ public class AttachmentManager {
     this.attachmentListener = listener;
 
     removableMediaView.setRemoveClickListener(new RemoveButtonListener());
+    thumbnail.setOnClickListener(new ThumbnailClickListener());
   }
 
   public void clear() {
@@ -274,6 +275,23 @@ public class AttachmentManager {
           constraints.canResize(slide.asAttachment());
   }
 
+  private void previewImageDraft(final @NonNull Slide slide) {
+    if (MediaPreviewActivity.isContentTypeSupported(slide.getContentType()) && slide.getThumbnailUri() != null) {
+      Intent intent = new Intent(context, MediaPreviewActivity.class);
+      intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
+      intent.setDataAndType(slide.getUri(), slide.getContentType());
+
+      context.startActivity(intent);
+    }
+  }
+
+  private class ThumbnailClickListener implements View.OnClickListener {
+    @Override
+    public void onClick(View v) {
+      if (slide.isPresent()) previewImageDraft(slide.get());
+    }
+  }
+
   private class RemoveButtonListener implements View.OnClickListener {
     @Override
     public void onClick(View v) {