--- a/mobile/android/base/LightweightTheme.java
+++ b/mobile/android/base/LightweightTheme.java
@@ -108,28 +108,30 @@ public class LightweightTheme implements
         } catch(java.net.MalformedURLException e) {
             mBitmap = null;
         } catch(java.io.IOException e) {
             mBitmap = null;
         }
     }
 
     public void resetLightweightTheme() {
-        // Reset the bitmap.
-        mBitmap = null;
+        if (mBitmap != null) {
+            // Reset the bitmap.
+            mBitmap = null;
 
-        // Post the reset on the UI thread.
-        for (OnChangeListener listener : mListeners) {
-             final OnChangeListener oneListener = listener;
-             oneListener.post(new Runnable() {
-                 @Override
-                 public void run() {
-                     oneListener.onLightweightThemeReset();
-                 }
-             });
+            // Post the reset on the UI thread.
+            for (OnChangeListener listener : mListeners) {
+                 final OnChangeListener oneListener = listener;
+                 oneListener.post(new Runnable() {
+                     @Override
+                     public void run() {
+                         oneListener.onLightweightThemeReset();
+                     }
+                 });
+            }
         }
     }
 
     public void notifyListeners() {
         if (mBitmap == null)
             return;
 
         // Post the change on the UI thread.
@@ -157,16 +159,31 @@ public class LightweightTheme implements
             } else if (event.equals("LightweightTheme:Disable")) {
                 resetLightweightTheme();
             }
         } catch (Exception e) {
             Log.e(LOGTAG, "Exception handling message \"" + event + "\":", e);
         }
     }
 
+
+    /**
+     * A lightweight theme is enabled only if there is an active bitmap.
+     *
+     * @return True if the theme is enabled.
+     */
+    public boolean isEnabled() {
+        return (mBitmap != null);
+    }
+
+    /**
+     * Based on the luminance of the domanint color, a theme is classified as light or dark.
+     *
+     * @return True if the theme is light.
+     */
     public boolean isLightTheme() {
         return mIsLight;
     }
 
     /**
      * Crop the image based on the position of the view on the window.
      * Either the View or one of its ancestors might have scrolled or translated.
      * This value should be taken into account while mapping the View to the Bitmap.