[Android] TopTabs font family (#2342)

* Add topTabTextFontFamily style option

* Add topTabTextFontFamily sample usage to example project

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

@@ -125,6 +125,7 @@ public class StyleParams {
     public Font titleBarButtonFontFamily;
 
     public Color topTabTextColor;
+    public Font topTabTextFontFamily;
     public Color topTabIconColor;
     public Color selectedTopTabTextColor;
     public Color selectedTopTabIconColor;

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

@@ -71,6 +71,7 @@ public class StyleParamsParser {
         result.topTabsHidden = getBoolean("topTabsHidden", getDefaultTopTabsHidden());
 
         result.topTabTextColor = getColor("topTabTextColor", getDefaultTopTabTextColor());
+        result.topTabTextFontFamily = getFont("topTabTextFontFamily", getDefaultTopTabTextFontFamily());
         result.topTabIconColor = getColor("topTabIconColor", getDefaultTopTabIconColor());
         result.selectedTopTabIconColor = getColor("selectedTopTabIconColor", getDefaultSelectedTopTabIconColor());
         result.selectedTopTabTextColor = getColor("selectedTopTabTextColor", getDefaultSelectedTopTabTextColor());
@@ -125,6 +126,7 @@ public class StyleParamsParser {
         result.titleBarTitleFont = new StyleParams.Font();
         result.titleBarSubtitleFontFamily = new StyleParams.Font();
         result.titleBarButtonFontFamily = new StyleParams.Font();
+        result.topTabTextFontFamily = new StyleParams.Font();
         result.titleBarHeight = -1;
         result.screenAnimationType = "slide-up";
         return result;
@@ -306,6 +308,10 @@ public class StyleParamsParser {
         return AppStyle.appStyle == null ? new StyleParams.Font() : AppStyle.appStyle.titleBarSubtitleFontFamily;
     }
 
+    private StyleParams.Font getDefaultTopTabTextFontFamily() {
+        return AppStyle.appStyle == null ? new StyleParams.Font() : AppStyle.appStyle.topTabTextFontFamily;
+    }
+
     private StyleParams.Font getDefaultTitleBarButtonFont() {
         return AppStyle.appStyle == null ? new StyleParams.Font() : AppStyle.appStyle.titleBarButtonFontFamily;
     }

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

@@ -213,6 +213,7 @@ public class TopBar extends AppBarLayout {
         topTabs.setTopTabsTextColor(style);
         topTabs.setSelectedTabIndicatorStyle(style);
         topTabs.setScrollable(style);
+        topTabs.setTopTabsTextFontFamily(style);
     }
 
     public void showContextualMenu(final ContextualMenuParams params, StyleParams styleParams, Callback onButtonClicked) {

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

@@ -2,7 +2,11 @@ package com.reactnativenavigation.views;
 
 import android.content.Context;
 import android.content.res.ColorStateList;
+import android.graphics.Typeface;
 import android.support.design.widget.TabLayout;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.TextView;
 
 import com.reactnativenavigation.params.StyleParams;
 import com.reactnativenavigation.views.utils.TopTabsIconColorHelper;
@@ -39,6 +43,24 @@ public class TopTabs extends TabLayout {
         setTabTextColors(tabTextColor, selectedTabColor);
     }
 
+    void setTopTabsTextFontFamily(StyleParams style) {
+        if (style.topTabTextFontFamily.hasFont()) {
+            ViewGroup viewGroup = (ViewGroup) this.getChildAt(0);
+
+            for (int tab = 0; tab < viewGroup.getChildCount(); tab++) {
+                ViewGroup tabViewGroup = (ViewGroup) viewGroup.getChildAt(tab);
+
+                for (int i = 0; i < tabViewGroup.getChildCount(); i++) {
+                    View tabViewChild = tabViewGroup.getChildAt(i);
+                    if (tabViewChild instanceof TextView) {
+                        ((TextView) tabViewChild).setTypeface(
+                                style.topTabTextFontFamily.get(), Typeface.NORMAL);
+                    }
+                }
+            }
+        }
+    }
+
     void setScrollable(StyleParams style) {
         if (style.topTabsScrollable) {
             setTabMode(TabLayout.MODE_SCROLLABLE);

example/src/screens/types/TopTabs.js

@@ -4,6 +4,7 @@ import {PixelRatio} from 'react-native';
 class TopTabs extends React.Component {
   static navigatorStyle = {
     topTabTextColor: '#ffffff',
+    topTabTextFontFamily: 'BioRhyme-Bold',
     selectedTopTabTextColor: '#ff505c',
 
     // Icons

src/deprecated/platformSpecificDeprecated.android.js

@@ -190,6 +190,7 @@ function convertStyleParams(originalStyleObject) {
     drawBelowTopBar: !originalStyleObject.drawUnderNavBar,
 
     topTabTextColor: processColor(originalStyleObject.topTabTextColor),
+    topTabTextFontFamily: originalStyleObject.topTabTextFontFamily,
     topTabIconColor: processColor(originalStyleObject.topTabIconColor),
     selectedTopTabIconColor: processColor(originalStyleObject.selectedTopTabIconColor),
     selectedTopTabTextColor: processColor(originalStyleObject.selectedTopTabTextColor),