How to align title at center of ActionBar in default theme(Theme.Holo.Light)

You can create a custom layout and apply it to the actionBar.

To do so, follow those 2 simple steps:

1. Java Code

   getSupportActionBar().setDisplayOptions(ActionBar.DISPLAY_SHOW_CUSTOM);
   getSupportActionBar().setCustomView(R.layout.actionbar);
   

Where R.layout.actionbar is the following layout.

2. XML

   <?xml version="1.0" encoding="utf-8"?>
   <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
       android:layout_width="match_parent"
       android:layout_height="wrap_content"
       android:layout_gravity="center"
       android:orientation="vertical">
   
   <TextView
       android:layout_width="wrap_content"
       android:layout_height="wrap_content"
       android:layout_gravity="center"
       android:id="@+id/action_bar_title"
       android:text="YOUR ACTIVITY TITLE"
       android:textColor="#ffffff"
       android:textSize="24sp" />
   </LinearLayout>
   

It can be as complex as you want. Try it out!

EDIT:

To set the background you can use the property android:background in the container layout (LinearLayout in that case). You may need to set the layout height android:layout_height to match_parent instead of wrap_content.

Moreover, you can also add a LOGO / ICON to it. To do so, simply add an ImageView inside your layout, and set layout orientation property android:orientation to horizontal (or simply use a RelativeLayout and manage it by yourself).

To change the title of above custom action bar dynamically, do this:

TextView title=(TextView)findViewById(getResources().getIdentifier("action_bar_title", "id", getPackageName()));
title.setText("Your Text Here");

It seems there is no way to do this without custom view. You can get the title view:

View decor = getWindow().getDecorView();
TextView title = (TextView) decor.findViewById(getResources().getIdentifier("action_bar_title", "id", "android"));

But changing of gravity or layout_gravity doesn't have an effect. The problem in the ActionBarView, which layout its children by itself so changing of layout params of its children also doesn't have an effect. To see this excecute following code:

ViewGroup actionBar = (ViewGroup) decor.findViewById(getResources().getIdentifier("action_bar", "id", "android"));
View v = actionBar.getChildAt(0);
ActionBar.LayoutParams p = new ActionBar.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT);
p.gravity= Gravity.CENTER;
v.setLayoutParams(p);
v.setBackgroundColor(Color.BLACK);