XML : PageTitles for Custom ViewPager

The following is my XML, with my PagerTitleStrip embedded into the ViewPager:

      <android.support.v4.view.ViewPager          xmlns:android="http://schemas.android.com/apk/res/android"          android:id="@+id/view_pager"          android:layout_width="match_parent"          android:layout_height="500dp"          android:scaleType="centerCrop">            <android.support.v4.view.PagerTitleStrip              android:layout_width="wrap_content"              android:layout_height="wrap_content"              android:background="@color/white"              android:layout_gravity="top" />        </android.support.v4.view.ViewPager>    

And this is my custom PagerAdapter class.

  public class CustomPagerAdapter extends PagerAdapter {        private int[] image_resources = {              R.drawable.1,              R.drawable.2,              R.drawable.3      };      private Context ctx;      private LayoutInflater layoutInflater;      public CustomPagerAdapter(Context ctx) {          this.ctx = ctx;      }        @Override      public int getCount() {          return image_resources.length;      }        @Override      public boolean isViewFromObject(View view, Object o) {          return (view == (RelativeLayout) o);      }        @Override      public CharSequence getPageTitle(int position) {          return "Title Here";      }        @Override      public Object instantiateItem(ViewGroup container, int position) {          layoutInflater = (LayoutInflater) ctx.getSystemService(Context.LAYOUT_INFLATER_SERVICE);          View item_view = layoutInflater.inflate(R.layout.pager_item, container, false);          ImageView imageview = (ImageView) item_view.findViewById(R.id.image_view);          imageview.setImageResource(image_resources[position]);          container.addView(item_view);          return item_view;      }        @Override      public void destroyItem(ViewGroup container, int position, Object object) {          container.removeView((RelativeLayout) object);      }  }    

Currently, getPageTitle only returns a constant String. How do I return a unique title for each image?