android: show loading animation until the document is loaded

Change-Id: I98eeafe30e90d039175daea65428526a95c9ff1e

android/experimental/LOAndroid3/res/layout/activity_main.xml

@@ -44,4 +44,16 @@
         android:background="#9FFF"
         android:choiceMode="singleChoice"/>
 
+    <RelativeLayout
+        android:id="@+id/loadingPanel"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:gravity="center" >
+
+        <ProgressBar
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:indeterminate="true" />
+    </RelativeLayout>
+
 </android.support.v4.widget.DrawerLayout>

android/experimental/LOAndroid3/src/java/org/libreoffice/LOKitThread.java

@@ -76,6 +76,13 @@ public class LOKitThread extends Thread {
         boolean isReady = mTileProvider.isReady();
         if (isReady) {
             refresh();
+            LOKitShell.getMainHandler().post(new Runnable() {
+                @Override
+                public void run() {
+                    LibreOfficeMainActivity.mAppContext.hideProgressBar();
+                }
+            });
+
         }
         return isReady;
     }

android/experimental/LOAndroid3/src/java/org/libreoffice/LibreOfficeMainActivity.java

@@ -195,6 +195,14 @@ public class LibreOfficeMainActivity extends Activity {
 
     }
 
+    public void showProgressBar() {
+        findViewById(R.id.loadingPanel).setVisibility(View.VISIBLE);
+    }
+
+    public void hideProgressBar() {
+        findViewById(R.id.loadingPanel).setVisibility(View.GONE);
+    }
+
     private class DocumentPartClickListener implements android.widget.AdapterView.OnItemClickListener {
         @Override
         public void onItemClick(AdapterView<?> parent, View view, int position, long id) {