content: package com.viewpagerindicator.sample;
  
  import java.util.Random;
  
  import com.viewpagerindicator.PageIndicator;
  
  import android.support.v4.app.FragmentActivity;
  import android.support.v4.view.ViewPager;
  import android.view.Menu;
  import android.view.MenuItem;
  import android.widget.Toast;
  
  public abstract class BaseSampleActivity extends FragmentActivity {
      private static final Random RANDOM = new Random();
  
      TestFragmentAdapter mAdapter;
      ViewPager mPager;
      PageIndicator mIndicator;
  
      @Override
      public boolean onCreateOptionsMenu(Menu menu) {
          getMenuInflater().inflate(R.menu.menu, menu);
          return true;
      }
  
      @Override
      public boolean onOptionsItemSelected(MenuItem item) {
          switch (item.getItemId()) {
              case R.id.random:
                  final int page = RANDOM.nextInt(mAdapter.getCount());
                  Toast.makeText(this, "Changing to page " + page, Toast.LENGTH_SHORT);
                  mPager.setCurrentItem(page);
                  return true;
  
              case R.id.add_page:
                  if (mAdapter.getCount() < 10) {
                      mAdapter.setCount(mAdapter.getCount() + 1);
                      mIndicator.notifyDataSetChanged();
                  }
                  return true;
  
              case R.id.remove_page:
                  if (mAdapter.getCount() > 1) {
                      mAdapter.setCount(mAdapter.getCount() - 1);
                      mIndicator.notifyDataSetChanged();
                  }
                  return true;
          }
          return super.onOptionsItemSelected(item);
      }
  }
  