#439 Fixed black screen when pressed back button while loading new game

core/src/cz/nic/tablexia/game/games/kidnapping/KidnappingGame.java

@@ -88,6 +88,7 @@ public class KidnappingGame extends AbstractTablexiaGame<GameState> {
 	private Group ruleMessage;
 	private boolean ruleMessageShown = false;
 	private StandardTablexiaButton ruleButton;
+    private boolean isBackButtonAllowed;
 
     private DirectionSounds.SoundPack actualSoundPack;
 
@@ -104,6 +105,7 @@ public class KidnappingGame extends AbstractTablexiaGame<GameState> {
 
     @Override
     protected void gameLoaded(final java.util.Map<String, String> gameState) {
+        isBackButtonAllowed = false;
 		getStage().addActor(map = Map.MapFactory.createInstance(this, gfxLibrary, getData()));
 		map.setMapScale(MAP_SCALE);
 
@@ -210,7 +212,12 @@ public class KidnappingGame extends AbstractTablexiaGame<GameState> {
 		ruleMessageShown = true;
 	}
 
-	private void playRuleSound(float delay) {
+    @Override
+    public void backButtonPressed() {
+        if(isBackButtonAllowed) super.backButtonPressed();
+    }
+
+    private void playRuleSound(float delay) {
         Timer.schedule(new Timer.Task(){
             @Override
             public void run() {
@@ -241,6 +248,7 @@ public class KidnappingGame extends AbstractTablexiaGame<GameState> {
 						}
 					})));
 		}
+        isBackButtonAllowed = true;
 	}
 
     @Override