fix static

src/main/java/ru/touchin/roboswag/components/navigation/fragments/SimpleViewControllerFragment.java

@@ -64,6 +64,11 @@ public class SimpleViewControllerFragment<TState extends AbstractState, TActivit
         return viewControllerClass;
     }
 
+    @Override
+    protected boolean isStateRequired() {
+        return true;
+    }
+
     @SuppressWarnings("unchecked")
     @Override
     public void onCreate(@Nullable final Bundle savedInstanceState) {

src/main/java/ru/touchin/roboswag/components/navigation/fragments/StatelessTargetedViewControllerFragment.java

@@ -51,6 +51,11 @@ public class StatelessTargetedViewControllerFragment<TTargetState extends Abstra
         return createState(viewControllerClass, new DefaultState());
     }
 
+    @Override
+    protected boolean isStateRequired() {
+        return false;
+    }
+
     @NonNull
     @Override
     public AbstractState getState() {

src/main/java/ru/touchin/roboswag/components/navigation/fragments/StatelessViewControllerFragment.java

@@ -38,13 +38,6 @@ import ru.touchin.roboswag.core.log.Lc;
 public class StatelessViewControllerFragment<TActivity extends ViewControllerActivity<?>>
         extends SimpleViewControllerFragment<AbstractState, TActivity> {
 
-    @NonNull
-    @Override
-    public AbstractState getState() {
-        Lc.assertion("Trying to access to state of stateless fragment of " + getViewControllerClass());
-        return super.getState();
-    }
-
     /**
      * Creates {@link Bundle} which will store state and {@link ViewController}'s class.
      *
@@ -56,4 +49,16 @@ public class StatelessViewControllerFragment<TActivity extends ViewControllerAct
         return createState(viewControllerClass, new DefaultState());
     }
 
+    @NonNull
+    @Override
+    public AbstractState getState() {
+        Lc.assertion("Trying to access to state of stateless fragment of " + getViewControllerClass());
+        return super.getState();
+    }
+
+    @Override
+    protected boolean isStateRequired() {
+        return false;
+    }
+
 }

src/main/java/ru/touchin/roboswag/components/navigation/fragments/ViewControllerFragment.java

@@ -139,6 +139,13 @@ public abstract class ViewControllerFragment<TState extends AbstractState, TActi
     public abstract Class<? extends ViewController<TActivity,
             ? extends ViewControllerFragment<TState, TActivity>>> getViewControllerClass();
 
+    /**
+     * Returns if ViewControllerFragment requires state or not.
+     *
+     * @return true if state is required
+     */
+    protected abstract boolean isStateRequired();
+
     @SuppressWarnings("unchecked")
     @Override
     public void onCreate(@Nullable final Bundle savedInstanceState) {
@@ -154,8 +161,8 @@ public abstract class ViewControllerFragment<TState extends AbstractState, TActi
                 state = reserialize(state);
             }
             state.onCreate();
-        } else {
-            Lc.assertion("State is null");
+        } else if (isStateRequired()) {
+            Lc.assertion("State is required and null");
         }
         viewControllerSubscription = Observable
                 .combineLatest(activitySubject.distinctUntilChanged(), viewSubject.distinctUntilChanged(),