GX-4416 (#2)

* adding support for android centered title and custom font

* PR feedback

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

     public Color titleBarSubtitleColor;
     public Color titleBarButtonColor;
     public Color titleBarDisabledButtonColor;
+    public String titleBarTitleFont;
+    public boolean titleBarTitleTextCentered;
     public boolean backButtonHidden;
 
     public Color topTabTextColor;

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

         result.titleBarSubtitleColor = getColor("titleBarSubtitleColor", getDefaultSubtitleBarColor());
         result.titleBarButtonColor = getColor("titleBarButtonColor", getTitleBarButtonColor());
         result.titleBarDisabledButtonColor = getColor("titleBarDisabledButtonColor", getTitleBarDisabledButtonColor());
+        result.titleBarTitleFont = getString("titleBarTitleFont", "");
+        result.titleBarTitleTextCentered = getBoolean("titleBarTitleTextCentered", false);
         result.backButtonHidden = getBoolean("backButtonHidden", getDefaultBackButtonHidden());
         result.topTabsHidden = getBoolean("topTabsHidden", getDefaultTopTabsHidden());
 
     private int getInt(String key, int defaultValue) {
         return params.containsKey(key) ? params.getInt(key) : defaultValue;
     }
+
+    private String getString(String key, String defaultValue) {
+        return params.containsKey(key) ? params.getString(key) : defaultValue;
+    }
+
 }

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

 import android.animation.Animator;
 import android.animation.AnimatorListenerAdapter;
 import android.content.Context;
+import android.graphics.Point;
+import android.graphics.Typeface;
 import android.graphics.drawable.Drawable;
 import android.support.annotation.Nullable;
 import android.support.v7.widget.ActionMenuView;
 import android.support.v7.widget.Toolbar;
+import android.view.Display;
 import android.view.Menu;
 import android.view.View;
+import android.view.WindowManager;
 import android.view.animation.AccelerateDecelerateInterpolator;
 import android.view.animation.AccelerateInterpolator;
 import android.widget.TextView;
     private static final int TITLE_VISIBILITY_ANIMATION_DURATION = 320;
     private LeftButton leftButton;
     private ActionMenuView actionMenuView;
+    private boolean titleBarTitleTextCentered;
 
     public TitleBar(Context context) {
         super(context);
     }
 
+    @Override
+    protected void onLayout(boolean changed, int l, int t, int r, int b) {
+        super.onLayout(changed, l, t, r, b);
+
+        if (titleBarTitleTextCentered) {
+            WindowManager windowManager = (WindowManager) getContext().getSystemService(Context.WINDOW_SERVICE);
+            Display display = windowManager.getDefaultDisplay();
+            Point screenSize = new Point();
+            display.getSize(screenSize);
+
+            int[] location = new int[2];
+            getTitleView().getLocationOnScreen(location);
+            getTitleView().setTranslationX(getTitleView().getTranslationX() + (-location[0] + screenSize.x / 2 - getTitleView().getWidth() / 2));
+        }
+    }
+
     @Override
     public void onViewAdded(View child) {
         super.onViewAdded(child);
     }
 
     public void setStyle(StyleParams params) {
+        titleBarTitleTextCentered = params.titleBarTitleTextCentered;
         setVisibility(params.titleBarHidden ? GONE : VISIBLE);
         setTitleTextColor(params);
+        setTitleTextFont(params);
         setSubtitleTextColor(params);
         colorOverflowButton(params);
         setBackground(params);
         }
     }
 
+    protected void setTitleTextFont(StyleParams params) {
+        if (params.titleBarTitleFont == null || params.titleBarTitleFont.isEmpty()) {
+            return;
+        }
+
+        View titleView = getTitleView();
+
+        if (titleView == null || !(titleView instanceof TextView)) {
+            return;
+        }
+
+        Typeface typeface = null;
+
+        try {
+            typeface = Typeface.createFromAsset(getContext().getAssets(), "fonts/" + params.titleBarTitleFont + ".ttf");
+        } catch (RuntimeException re) {
+            try {
+                typeface = Typeface.createFromAsset(getContext().getAssets(), "fonts/" + params.titleBarTitleFont + ".otf");
+            } catch (RuntimeException re2) {
+                return;
+            }
+        }
+        ((TextView) titleView).setTypeface(typeface);
+    }
+
     protected void setSubtitleTextColor(StyleParams params) {
         if (params.titleBarSubtitleColor.hasColor()) {
             setSubtitleTextColor(params.titleBarSubtitleColor.getColor());

src/deprecated/platformSpecificDeprecated.android.js

     titleBarSubtitleColor: processColor(originalStyleObject.navBarSubtitleColor),
     titleBarButtonColor: processColor(originalStyleObject.navBarButtonColor),
     titleBarDisabledButtonColor: processColor(originalStyleObject.titleBarDisabledButtonColor),
+    titleBarTitleFont: originalStyleObject.navBarTitleFont,
+    titleBarTitleTextCentered: originalStyleObject.navBarTitleTextCentered,
     backButtonHidden: originalStyleObject.backButtonHidden,
     topTabsHidden: originalStyleObject.topTabsHidden,
     contextualMenuStatusBarColor: processColor(originalStyleObject.contextualMenuStatusBarColor),