merged from master

android/app/src/main/java/com/reactnativenavigation/layouts/SingleScreenLayout.java

     }
 
     private void createLayout() {
-        if (leftSideMenuParams == null) {
+        if (leftSideMenuParams == null && rightSideMenuParams == null) {
             createStack(getScreenStackParent());
         } else {
             sideMenu = createSideMenu();

android/app/src/main/java/com/reactnativenavigation/params/BaseScreenParams.java

 public class BaseScreenParams {
     public String screenId;
     public String title;
+    public String subtitle;
     public NavigationParams navigationParams;
     public List<TitleBarButtonParams> rightButtons;
     public TitleBarLeftButtonParams leftButton;

android/app/src/main/java/com/reactnativenavigation/params/StyleParams.java

     public Color topBarColor;
     public CollapsingTopBarParams collapsingTopBarParams;
     public boolean topBarHidden;
+    public boolean topBarElevationShadowEnabled;
     public boolean topTabsHidden;
     public boolean drawScreenBelowTopBar;
 

android/app/src/main/java/com/reactnativenavigation/params/parsers/ScreenParamsParser.java

 
 public class ScreenParamsParser extends Parser {
     private static final String KEY_TITLE = "title";
+    private static final String KEY_SUBTITLE = "subtitle";
     private static final String KEY_SCREEN_ID = "screenId";
     private static final String KEY_NAVIGATION_PARAMS = "navigationParams";
     private static final String STYLE_PARAMS = "styleParams";
         result.styleParams = new StyleParamsParser(params.getBundle(STYLE_PARAMS)).parse();
 
         result.title = params.getString(KEY_TITLE);
+        result.subtitle = params.getString(KEY_SUBTITLE);
         result.rightButtons = ButtonParser.parseRightButton(params);
         result.overrideBackPressInJs = params.getBoolean(OVERRIDE_BACK_PRESS, false);
         result.leftButton = ButtonParser.parseLeftButton(params);

android/app/src/main/java/com/reactnativenavigation/params/parsers/StyleParamsParser.java

         StyleParams result = new StyleParams();
         if (params == null) {
             result.titleBarDisabledButtonColor = getTitleBarDisabledButtonColor();
+            result.topBarElevationShadowEnabled = true;
             return result;
         }
 
         result.collapsingTopBarParams = new CollapsingTopBarParamsParser(params).parse();
         result.titleBarHidden = getBoolean("titleBarHidden", getDefaultTopBarHidden());
         result.topBarTransparent = getBoolean("topBarTransparent", getDefaultTopBarHidden());
+        result.topBarElevationShadowEnabled = getBoolean("topBarElevationShadowEnabled", getDefaultTopBarElevationShadowEnabled());
         result.titleBarTitleColor = getColor("titleBarTitleColor", getDefaultTitleBarColor());
         result.topBarTranslucent = getBoolean("topBarTranslucent", getDefaultTopBarTranslucent());
         result.titleBarHideOnScroll = getBoolean("titleBarHideOnScroll", getDefaultTitleBarHideOnScroll());
         return AppStyle.appStyle != null && AppStyle.appStyle.topBarTransparent;
     }
 
+    private boolean getDefaultTopBarElevationShadowEnabled() {
+        return AppStyle.appStyle == null || AppStyle.appStyle.topBarElevationShadowEnabled;
+    }
+
     private boolean getDefaultTopBarTranslucent() {
         return AppStyle.appStyle != null && AppStyle.appStyle.topBarTranslucent;
     }

android/app/src/main/java/com/reactnativenavigation/screens/Screen.java

     private void createTitleBar() {
         addTitleBarButtons();
         topBar.setTitle(screenParams.title);
+        topBar.setSubtitle(screenParams.subtitle);
     }
 
     private void addTitleBarButtons() {

android/app/src/main/java/com/reactnativenavigation/views/TopBar.java

         setVisibility(styleParams.topBarHidden ? GONE : VISIBLE);
         titleBar.setStyle(styleParams);
         setTopTabsStyle(styleParams);
+        if (!styleParams.topBarElevationShadowEnabled) {
+            disableElevationShadow();
+        }
     }
 
     private void setTransparent() {
         setBackgroundColor(Color.TRANSPARENT);
+        disableElevationShadow();
+    }
+
+    private void disableElevationShadow() {
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
             setOutlineProvider(null);
         }

example/scripts/postinstall.js

 const cp = require('child_process');
 cp.execSync(`rm -rf node_modules/react-native-navigation/node_modules`);
 cp.execSync(`rm -rf node_modules/react-native-navigation/example `);
-cp.execSync(`rm -rf yarn.lock`);

example/src/screens/PushedScreen.js

   onResetToPress() {
     this.props.navigator.resetTo({
       title: "New Root",
-      screen: "example.ThirdTabScreen"
+      screen: "example.StyledScreen",
+      animated: true
     });
   }
 }

src/deprecated/platformSpecificDeprecated.android.js

     topBarColor: processColor(originalStyleObject.navBarBackgroundColor),
     topBarTransparent: originalStyleObject.navBarTransparent,
     topBarTranslucent: originalStyleObject.navBarTranslucent,
+    topBarElevationShadowEnabled: originalStyleObject.topBarElevationShadowEnabled,
     collapsingToolBarImage: originalStyleObject.collapsingToolBarImage,
     collapsingToolBarCollapsedColor: processColor(originalStyleObject.collapsingToolBarCollapsedColor),
     titleBarHidden: originalStyleObject.navBarHidden,

src/deprecated/platformSpecificDeprecated.ios.js

                                disableOpenGesture={params.drawer.disableOpenGesture}
                                type={params.drawer.type ? params.drawer.type : 'MMDrawer'}
                                animationType={params.drawer.animationType ? params.drawer.animationType : 'slide'}
+                               style={params.drawer.style}
           >
             {this.renderBody()}
           </DrawerControllerIOS>
                                disableOpenGesture={params.drawer.disableOpenGesture}
                                type={params.drawer.type ? params.drawer.type : 'MMDrawer'}
                                animationType={params.drawer.animationType ? params.drawer.animationType : 'slide'}
+                               style={params.drawer.style}
           >
             {this.renderBody()}
           </DrawerControllerIOS>