Implement backButtonHidden

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

         eventId = params.eventId;
         enabled = params.enabled;
     }
+
+    public boolean isBackButton() {
+        return eventId.equals("back");
+    }
 }

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

 package com.reactnativenavigation.params.parsers;
 
+import android.graphics.drawable.Drawable;
 import android.os.Bundle;
 
 import com.reactnativenavigation.params.ScreenParams;
+import com.reactnativenavigation.params.TitleBarButtonParams;
+import com.reactnativenavigation.params.TitleBarLeftButtonParams;
+import com.reactnativenavigation.params.TopTabParams;
 import com.reactnativenavigation.react.ImageLoader;
 
 import java.util.ArrayList;
     private static final String KEY_NAVIGATION_PARAMS = "navigationParams";
     private static final String KEY_RIGHT_BUTTONS = "rightButtons";
     private static final String KEY_LEFT_BUTTON = "leftButton";
+    private static final String KEY_BACK_BUTTON_HIDDEN = "backButtonHidden";
     private static final String STYLE_PARAMS = "styleParams";
     private static final String TOP_TABS = "topTabs";
     private static final String FRAGMENT_CREATOR_CLASS_NAME = "fragmentCreatorClassName";
         result.navigationParams = params.getBundle(KEY_NAVIGATION_PARAMS);
         result.navigatorEventId = result.navigationParams.getString(KEY_NAVIGATOR_EVENT_ID);
         result.screenInstanceId = result.navigationParams.getString(KEY_SCREEN_INSTANCE_ID);
-        if (hasKey(params, KEY_RIGHT_BUTTONS)) {
-            result.rightButtons = new TitleBarButtonParamsParser().parseButtons(params.getBundle(KEY_RIGHT_BUTTONS));
-        }
-        if (hasKey(params, KEY_LEFT_BUTTON)) {
-            result.leftButton = new TitleBarLeftButtonParamsParser().parseSingleButton(params.getBundle(KEY_LEFT_BUTTON));
-        }
-        result.title = params.getString(KEY_TITLE);
+
         result.styleParams = new StyleParamsParser(params.getBundle(STYLE_PARAMS)).parse();
-        if (hasKey(params, TOP_TABS)) {
-            result.topTabParams = TopTabParamsParser.parse(params.getBundle(TOP_TABS));
-        }
+
+        result.title = params.getString(KEY_TITLE);
+        result.rightButtons = parseRightButton(params);
+        result.leftButton = parseLeftButton(params);
+
+        result.topTabParams = parseTopTabs(params);
+
         if (hasKey(params, FRAGMENT_CREATOR_CLASS_NAME)) {
             result.fragmentCreatorClassName = params.getString(FRAGMENT_CREATOR_CLASS_NAME);
             result.fragmentCreatorPassProps = params.getBundle(FRAGMENT_CREATOR_PASS_PROPS);
         }
+
+        result.tabLabel = getTabLabel(params);
+        result.tabIcon = getTabIcon(params);
+
+        result.animateScreenTransitions = params.getBoolean("animated", true);
+
+        return result;
+    }
+
+    private static Drawable getTabIcon(Bundle params) {
+        Drawable tabIcon = null;
+        if (hasKey(params, "icon")) {
+            tabIcon = ImageLoader.loadImage(params.getString("icon"));
+        }
+        return tabIcon;
+    }
+
+    private static String getTabLabel(Bundle params) {
+        String tabLabel = null;
         if (hasKey(params, "label")) {
-            result.tabLabel = params.getString("label");
+            tabLabel = params.getString("label");
         }
-        if (hasKey(params, "icon")) {
-            result.tabIcon = ImageLoader.loadImage(params.getString("icon"));
+        return tabLabel;
+    }
+
+    private static List<TopTabParams> parseTopTabs(Bundle params) {
+        List<TopTabParams> topTabParams = null;
+        if (hasKey(params, TOP_TABS)) {
+             topTabParams = TopTabParamsParser.parse(params.getBundle(TOP_TABS));
         }
-        result.animateScreenTransitions = params.getBoolean("animated", true);
-        return result;
+        return topTabParams;
+    }
+
+    private static List<TitleBarButtonParams> parseRightButton(Bundle params) {
+        List<TitleBarButtonParams> rightButtons = null;
+        if (hasKey(params, KEY_RIGHT_BUTTONS)) {
+            rightButtons = new TitleBarButtonParamsParser().parseButtons(params.getBundle(KEY_RIGHT_BUTTONS));
+        }
+        return rightButtons;
+    }
+
+    private static TitleBarLeftButtonParams parseLeftButton(Bundle params) {
+        TitleBarLeftButtonParams leftButton = null;
+        if (hasKey(params, KEY_LEFT_BUTTON)) {
+            leftButton =  new TitleBarLeftButtonParamsParser().parseSingleButton(params.getBundle(KEY_LEFT_BUTTON));
+
+            boolean backButtonHidden = params.getBoolean(KEY_BACK_BUTTON_HIDDEN, false);
+            if (backButtonHidden && leftButton.isBackButton()) {
+                leftButton = null;
+            }
+        }
+        return leftButton;
     }
 
     public static List<ScreenParams> parseTabs(Bundle params) {