Null check tabTestId

lib/android/app/src/main/java/com/reactnativenavigation/utils/ObjectUtils.java

@@ -0,0 +1,13 @@
+package com.reactnativenavigation.utils;
+
+import android.support.annotation.Nullable;
+
+public class ObjectUtils {
+    public interface Action<T> {
+        void performOn(T obj);
+    }
+
+    public static <T> void perform(@Nullable T obj, Action<T> action) {
+        if (obj != null) action.performOn(obj);
+    }
+}

lib/android/app/src/main/java/com/reactnativenavigation/views/BottomTabs.java

@@ -4,13 +4,14 @@ import android.annotation.SuppressLint;
 import android.content.Context;
 import android.support.annotation.ColorInt;
 import android.support.annotation.IntRange;
-import android.view.View;
 
 import com.aurelhubert.ahbottomnavigation.AHBottomNavigation;
 import com.reactnativenavigation.BuildConfig;
 import com.reactnativenavigation.parse.params.Text;
 import com.reactnativenavigation.utils.CompatUtils;
 
+import static com.reactnativenavigation.utils.ObjectUtils.perform;
+
 @SuppressLint("ViewConstructor")
 public class BottomTabs extends AHBottomNavigation {
     public BottomTabs(Context context) {
@@ -20,10 +21,11 @@ public class BottomTabs extends AHBottomNavigation {
     }
 
     public void setTabTestId(int index, Text testId) {
-        if (!testId.hasValue()) return;
-        View view = getViewAtPosition(index);
-        view.setTag(testId.get());
-        if (BuildConfig.DEBUG) view.setContentDescription(testId.get());
+        if (!testId.hasValue() ) return;
+        perform(getViewAtPosition(index), view -> {
+            view.setTag(testId.get());
+            if (BuildConfig.DEBUG) view.setContentDescription(testId.get());
+        });
     }
 
     public void setBadge(int bottomTabIndex, String badge) {