Add default style handling for ThemeSwitcher

Author: danesfeder

libandroid-navigation-ui/src/main/java/com/mapbox/services/android/navigation/ui/v5/ThemeSwitcher.java

@@ -3,6 +3,7 @@
 import android.content.Context;
 import android.content.SharedPreferences;
 import android.content.res.Configuration;
+import android.content.res.Resources;
 import android.content.res.TypedArray;
 import android.graphics.drawable.Drawable;
 import android.preference.PreferenceManager;
@@ -68,12 +69,17 @@ public static Drawable retrieveThemeOverviewDrawable(Context context) {
    * for the given resId set in the theme.
    *
    * @param context    to retrieve the resolved attribute
-   * @param styleResId for the given style
+   * @param attributeId for the given style
    * @return resolved style resource Id
    */
-  public static int retrieveNavigationViewStyle(Context context, int styleResId) {
-    TypedValue outValue = resolveAttributeFromId(context, styleResId);
-    return outValue.resourceId;
+  public static int retrieveNavigationViewResId(Context context, int attributeId, int defaultStyleId) {
+    TypedValue outValue = new TypedValue();
+    Resources.Theme theme = context.getTheme();
+    if (theme.resolveAttribute(attributeId, outValue, true)) {
+      return outValue.resourceId;
+    } else {
+      return defaultStyleId;
+    }
   }
 
   /**

libandroid-navigation-ui/src/main/java/com/mapbox/services/android/navigation/ui/v5/map/NavigationMapboxMap.java

@@ -551,12 +551,11 @@ private void initializeLocationComponent(MapView mapView, MapboxMap map) {
   }
 
   private int findLayerStyleRes(Context context) {
-    int locationLayerStyleRes = ThemeSwitcher.retrieveNavigationViewStyle(context,
-      R.attr.navigationViewLocationLayerStyle);
-    if (locationLayerStyleRes == INVLAID_LAYER_STYLE) {
-      locationLayerStyleRes = R.style.NavigationLocationLayerStyle;
-    }
-    return locationLayerStyleRes;
+    return ThemeSwitcher.retrieveNavigationViewResId(
+      context,
+      R.attr.navigationViewLocationLayerStyle,
+      R.style.NavigationLocationLayerStyle
+    );
   }
 
   private void initializeMapPaddingAdjustor(MapView mapView, MapboxMap mapboxMap) {
@@ -605,7 +604,9 @@ private Source findSourceByUrl(List<Source> sources, String streetsUrl) {
 
   private void initializeRoute(MapView mapView, MapboxMap map) {
     Context context = mapView.getContext();
-    int routeStyleRes = ThemeSwitcher.retrieveNavigationViewStyle(context, R.attr.navigationViewRouteStyle);
+    int routeStyleRes = ThemeSwitcher.retrieveNavigationViewResId(
+      context, R.attr.navigationViewRouteStyle, R.style.NavigationMapRoute
+    );
     mapRoute = new NavigationMapRoute(null, mapView, map, routeStyleRes);
   }