diff --git a/MyTracks/src/com/google/android/apps/mytracks/MapOverlay.java b/MyTracks/src/com/google/android/apps/mytracks/MapOverlay.java
index f8d74bb02..d8f233cdd 100644
--- a/MyTracks/src/com/google/android/apps/mytracks/MapOverlay.java
+++ b/MyTracks/src/com/google/android/apps/mytracks/MapOverlay.java
@@ -56,7 +56,17 @@ import java.util.concurrent.BlockingQueue;
  * 
  * @author Leif Hendrik Wilden
  */
-public class MapOverlay extends Overlay implements OnSharedPreferenceChangeListener {
+public class MapOverlay extends Overlay {
+
+  private final OnSharedPreferenceChangeListener
+      sharedPreferenceChangeListener = new OnSharedPreferenceChangeListener() {
+          @Override
+        public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, String key) {
+          if (PreferencesUtils.getKey(context, R.string.track_color_mode_key).equals(key)) {
+            trackPathPainter = TrackPathPainterFactory.getTrackPathPainter(context);
+          }
+        }
+      };
 
   private final Context context;
   private final List<Waypoint> waypoints;
@@ -181,7 +191,7 @@ public class MapOverlay extends Overlay implements OnSharedPreferenceChangeListe
     trackPathPainter = TrackPathPainterFactory.getTrackPathPainter(context);
 
     context.getSharedPreferences(Constants.SETTINGS_NAME, Context.MODE_PRIVATE)
-        .registerOnSharedPreferenceChangeListener(this);
+        .registerOnSharedPreferenceChangeListener(sharedPreferenceChangeListener);
   }
 
   /**
@@ -366,13 +376,6 @@ public class MapOverlay extends Overlay implements OnSharedPreferenceChangeListe
     return super.onTap(geoPoint, mapView);
   }
 
-  @Override
-  public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, String key) {
-    if (PreferencesUtils.getKey(context, R.string.track_color_mode_key).equals(key)) {
-      trackPathPainter = TrackPathPainterFactory.getTrackPathPainter(context);
-    }
-  }
-
   /**
    * Gets the points.
    */
diff --git a/MyTracks/src/com/google/android/apps/mytracks/maps/DynamicSpeedTrackPathDescriptor.java b/MyTracks/src/com/google/android/apps/mytracks/maps/DynamicSpeedTrackPathDescriptor.java
index 604d05954..cc26c7e35 100644
--- a/MyTracks/src/com/google/android/apps/mytracks/maps/DynamicSpeedTrackPathDescriptor.java
+++ b/MyTracks/src/com/google/android/apps/mytracks/maps/DynamicSpeedTrackPathDescriptor.java
@@ -37,8 +37,19 @@ import android.util.Log;
  * 
  * @author Vangelis S.
  */
-public class DynamicSpeedTrackPathDescriptor
-    implements TrackPathDescriptor, OnSharedPreferenceChangeListener {
+public class DynamicSpeedTrackPathDescriptor implements TrackPathDescriptor {
+
+  private final OnSharedPreferenceChangeListener
+      sharedPreferenceChangeListener = new OnSharedPreferenceChangeListener() {
+          @Override
+        public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, String key) {
+          if (PreferencesUtils.getKey(context, R.string.track_color_mode_percentage_key)
+              .equals(key)) {
+            speedMargin = PreferencesUtils.getInt(context, R.string.track_color_mode_percentage_key,
+                PreferencesUtils.TRACK_COLOR_MODE_PERCENTAGE_DEFAULT);
+          }
+        }
+      };
 
   private final Context context;
   private int speedMargin;
@@ -54,7 +65,7 @@ public class DynamicSpeedTrackPathDescriptor
     speedMargin = PreferencesUtils.getInt(context, R.string.track_color_mode_percentage_key,
         PreferencesUtils.TRACK_COLOR_MODE_PERCENTAGE_DEFAULT);
     context.getSharedPreferences(Constants.SETTINGS_NAME, Context.MODE_PRIVATE)
-        .registerOnSharedPreferenceChangeListener(this);
+        .registerOnSharedPreferenceChangeListener(sharedPreferenceChangeListener);
   }
 
   @Override
@@ -93,14 +104,6 @@ public class DynamicSpeedTrackPathDescriptor
     }
   }
 
-  @Override
-  public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, String key) {
-    if (PreferencesUtils.getKey(context, R.string.track_color_mode_percentage_key).equals(key)) {
-      speedMargin = PreferencesUtils.getInt(context, R.string.track_color_mode_percentage_key,
-          PreferencesUtils.TRACK_COLOR_MODE_PERCENTAGE_DEFAULT);
-    }
-  }
-
   /**
    * Returns true if the average moving speed and the new average moving speed
    * are significantly different.
diff --git a/MyTracks/src/com/google/android/apps/mytracks/maps/FixedSpeedTrackPathDescriptor.java b/MyTracks/src/com/google/android/apps/mytracks/maps/FixedSpeedTrackPathDescriptor.java
index 56d0f3a8f..a07736306 100644
--- a/MyTracks/src/com/google/android/apps/mytracks/maps/FixedSpeedTrackPathDescriptor.java
+++ b/MyTracks/src/com/google/android/apps/mytracks/maps/FixedSpeedTrackPathDescriptor.java
@@ -29,8 +29,23 @@ import android.content.SharedPreferences.OnSharedPreferenceChangeListener;
  * 
  * @author Vangelis S.
  */
-public class FixedSpeedTrackPathDescriptor
-    implements TrackPathDescriptor, OnSharedPreferenceChangeListener {
+public class FixedSpeedTrackPathDescriptor implements TrackPathDescriptor {
+
+  private final OnSharedPreferenceChangeListener
+      sharedPreferenceChangeListener = new OnSharedPreferenceChangeListener() {
+          @Override
+        public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, String key) {
+          if (PreferencesUtils.getKey(context, R.string.track_color_mode_slow_key).equals(key)) {
+            slowSpeed = PreferencesUtils.getInt(context, R.string.track_color_mode_slow_key,
+                PreferencesUtils.TRACK_COLOR_MODE_SLOW_DEFAULT);
+          } else if (PreferencesUtils.getKey(context, R.string.track_color_mode_medium_key)
+              .equals(key)) {
+            normalSpeed = PreferencesUtils.getInt(context, R.string.track_color_mode_medium_key,
+                PreferencesUtils.TRACK_COLOR_MODE_MEDIUM_DEFAULT);
+          }
+        }
+      };
+
   private final Context context;
   private int slowSpeed;
   private int normalSpeed;
@@ -43,7 +58,7 @@ public class FixedSpeedTrackPathDescriptor
     normalSpeed = PreferencesUtils.getInt(context, R.string.track_color_mode_medium_key,
         PreferencesUtils.TRACK_COLOR_MODE_MEDIUM_DEFAULT);
     context.getSharedPreferences(Constants.SETTINGS_NAME, Context.MODE_PRIVATE)
-        .registerOnSharedPreferenceChangeListener(this);
+        .registerOnSharedPreferenceChangeListener(sharedPreferenceChangeListener);
   }
 
   @Override
@@ -60,15 +75,4 @@ public class FixedSpeedTrackPathDescriptor
   public boolean updateState() {
     return false;
   }
-
-  @Override
-  public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, String key) {
-    if (PreferencesUtils.getKey(context, R.string.track_color_mode_slow_key).equals(key)) {
-      slowSpeed = PreferencesUtils.getInt(context, R.string.track_color_mode_slow_key,
-          PreferencesUtils.TRACK_COLOR_MODE_SLOW_DEFAULT);
-    } else if (PreferencesUtils.getKey(context, R.string.track_color_mode_medium_key).equals(key)) {
-      normalSpeed = PreferencesUtils.getInt(context, R.string.track_color_mode_medium_key,
-          PreferencesUtils.TRACK_COLOR_MODE_MEDIUM_DEFAULT);
-    }
-  }
 }
\ No newline at end of file
diff --git a/MyTracks/src/com/google/android/apps/mytracks/widgets/TrackWidgetProvider.java b/MyTracks/src/com/google/android/apps/mytracks/widgets/TrackWidgetProvider.java
index c7fb0bda0..8ab33d1c5 100644
--- a/MyTracks/src/com/google/android/apps/mytracks/widgets/TrackWidgetProvider.java
+++ b/MyTracks/src/com/google/android/apps/mytracks/widgets/TrackWidgetProvider.java
@@ -52,8 +52,7 @@ import android.widget.RemoteViews;
  * @author Sandor Dornbush
  * @author Paul R. Saxman
  */
-public class TrackWidgetProvider extends AppWidgetProvider
-    implements OnSharedPreferenceChangeListener {
+public class TrackWidgetProvider extends AppWidgetProvider {
 
   /**
    * Observer for track content.
@@ -99,43 +98,50 @@ public class TrackWidgetProvider extends AppWidgetProvider
     handler = new Handler();
   }
 
-  @Override
-  public void onSharedPreferenceChanged(SharedPreferences preferences, String key) {
-    if (key == null
-        || key.equals(PreferencesUtils.getKey(context, R.string.selected_track_id_key))) {
-      selectedTrackId = PreferencesUtils.getLong(context, R.string.selected_track_id_key);
-    }
-    if (key == null
-        || key.equals(PreferencesUtils.getKey(context, R.string.recording_track_id_key))) {
-      long oldValue = recordingTrackId;
-      recordingTrackId = PreferencesUtils.getLong(context, R.string.recording_track_id_key);
-      if (oldValue == PreferencesUtils.RECORDING_TRACK_ID_DEFAULT
-          && recordingTrackId != PreferencesUtils.RECORDING_TRACK_ID_DEFAULT) {
-        recordingtrackPaused = false;
-      }
-    }
-    if (key == null
-        || key.equals(PreferencesUtils.getKey(context, R.string.recording_track_paused_key))) {
-      recordingtrackPaused = PreferencesUtils.getBoolean(context,
-          R.string.recording_track_paused_key, PreferencesUtils.RECORDING_TRACK_PAUSED_DEFAULT);
-    }
-    if (key == null || key.equals(PreferencesUtils.getKey(context, R.string.metric_units_key))) {
-      metricUnits = PreferencesUtils.getBoolean(
-          context, R.string.metric_units_key, PreferencesUtils.METRIC_UNITS_DEFAULT);
-    }
-    if (key == null || key.equals(PreferencesUtils.getKey(context, R.string.report_speed_key))) {
-      reportSpeed = PreferencesUtils.getBoolean(
-          context, R.string.report_speed_key, PreferencesUtils.REPORT_SPEED_DEFAULT);
-    }
-    if (key == null
-        || key.equals(PreferencesUtils.getKey(context, R.string.stats_show_moving_time_key))) {
-      showMovingTime = PreferencesUtils.getBoolean(context, R.string.stats_show_moving_time_key,
-          PreferencesUtils.STATS_SHOW_MOVING_TIME_DEFAULT);
-    }
-    if (key != null) {
-      update();
-    }
-  }
+  private final OnSharedPreferenceChangeListener
+      sharedPreferenceChangeListener = new OnSharedPreferenceChangeListener() {
+          @Override
+        public void onSharedPreferenceChanged(SharedPreferences preferences, String key) {
+          if (key == null
+              || key.equals(PreferencesUtils.getKey(context, R.string.selected_track_id_key))) {
+            selectedTrackId = PreferencesUtils.getLong(context, R.string.selected_track_id_key);
+          }
+          if (key == null
+              || key.equals(PreferencesUtils.getKey(context, R.string.recording_track_id_key))) {
+            long oldValue = recordingTrackId;
+            recordingTrackId = PreferencesUtils.getLong(context, R.string.recording_track_id_key);
+            if (oldValue == PreferencesUtils.RECORDING_TRACK_ID_DEFAULT
+                && recordingTrackId != PreferencesUtils.RECORDING_TRACK_ID_DEFAULT) {
+              recordingtrackPaused = false;
+            }
+          }
+          if (key == null || key.equals(
+              PreferencesUtils.getKey(context, R.string.recording_track_paused_key))) {
+            recordingtrackPaused = PreferencesUtils.getBoolean(context,
+                R.string.recording_track_paused_key,
+                PreferencesUtils.RECORDING_TRACK_PAUSED_DEFAULT);
+          }
+          if (key == null
+              || key.equals(PreferencesUtils.getKey(context, R.string.metric_units_key))) {
+            metricUnits = PreferencesUtils.getBoolean(
+                context, R.string.metric_units_key, PreferencesUtils.METRIC_UNITS_DEFAULT);
+          }
+          if (key == null
+              || key.equals(PreferencesUtils.getKey(context, R.string.report_speed_key))) {
+            reportSpeed = PreferencesUtils.getBoolean(
+                context, R.string.report_speed_key, PreferencesUtils.REPORT_SPEED_DEFAULT);
+          }
+          if (key == null || key.equals(
+              PreferencesUtils.getKey(context, R.string.stats_show_moving_time_key))) {
+            showMovingTime = PreferencesUtils.getBoolean(context,
+                R.string.stats_show_moving_time_key,
+                PreferencesUtils.STATS_SHOW_MOVING_TIME_DEFAULT);
+          }
+          if (key != null) {
+            update();
+          }
+        }
+      };
 
   @Override
   public void onReceive(Context aContext, Intent intent) {
@@ -150,8 +156,8 @@ public class TrackWidgetProvider extends AppWidgetProvider
       unknown = context.getString(R.string.value_unknown);
 
       sharedPreferences = context.getSharedPreferences(SETTINGS_NAME, Context.MODE_PRIVATE);
-      sharedPreferences.registerOnSharedPreferenceChangeListener(this);
-      onSharedPreferenceChanged(sharedPreferences, null);
+      sharedPreferences.registerOnSharedPreferenceChangeListener(sharedPreferenceChangeListener);
+      sharedPreferenceChangeListener.onSharedPreferenceChanged(sharedPreferences, null);
       context.getContentResolver()
           .registerContentObserver(TracksColumns.CONTENT_URI, true, trackObserver);
     }
@@ -165,7 +171,7 @@ public class TrackWidgetProvider extends AppWidgetProvider
   @Override
   public void onDisabled(Context aContext) {
     if (sharedPreferences != null) {
-      sharedPreferences.unregisterOnSharedPreferenceChangeListener(this);
+      sharedPreferences.unregisterOnSharedPreferenceChangeListener(sharedPreferenceChangeListener);
     }
     if (trackObserver != null) {
       aContext.getContentResolver().unregisterContentObserver(trackObserver);