Unmount custom TitleBar buttons

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

                 ((CollapsingContentView) contentView).destroy();
             }
         }
-        topBar.destroy();
     }
 
     protected ContentView getCurrentPage() {

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

         unmountReactView();
         EventBus.instance.unregister(this);
         sharedElements.destroy();
+        topBar.destroy();
     }
 }

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

             leftButton.updateNavigatorEventId(screenParams.getNavigatorEventId());
         }
     }
+
+    public void destroy() {
+        unmountCustomButtons();
+    }
+
+    private void unmountCustomButtons() {
+        for (int i = 0; i < actionMenuView.getChildCount(); i++) {
+            if (actionMenuView.getChildAt(i) instanceof TitleBarButtonComponent) {
+                ((ContentView) actionMenuView.getChildAt(i)).unmountReactView();
+            }
+        }
+    }
 }

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

-package com.reactnativenavigation.views;
-
-import android.content.Context;
-import android.support.annotation.Nullable;
-import android.view.Menu;
-import android.view.MenuItem;
-import android.view.View;
-
-import com.reactnativenavigation.params.NavigationParams;
-import com.reactnativenavigation.params.TitleBarButtonParams;
-
-class TitleBarCustomComponentButton extends TitleBarButton {
-    TitleBarCustomComponentButton(Menu menu, View parent, TitleBarButtonParams buttonParams, @Nullable String navigatorEventId) {
-        super(menu, parent, buttonParams, navigatorEventId);
-    }
-
-    @Override
-    MenuItem addToMenu(int index) {
-        throw new RuntimeException("Can't add custom component to menu");
-    }
-
-    View createView(Context context) {
-        return new ContentView(context, buttonParams.componentName, NavigationParams.EMPTY, buttonParams.componentProps);
-    }
-}

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

         if (reactView != null) {
             reactView.unmountReactView();
         }
+        titleBar.destroy();
     }
 
     public void onViewPagerScreenChanged(BaseScreenParams screenParams) {