SingleFragmentActivity.java

package org.adaptlab.chpir.android.survey;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.view.Window;

public abstract class SingleFragmentActivity extends FragmentActivity {

    protected abstract Fragment createFragment();

    protected int getLayoutResId() {
        return R.layout.activity_fragment;
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_INDETERMINATE_PROGRESS);
        setContentView(getLayoutResId());

        FragmentManager fm = getSupportFragmentManager();
        Fragment fragment = fm.findFragmentById(R.id.fragmentContainer);

        if (fragment == null) {
            fragment = createFragment();
            fm.beginTransaction().add(R.id.fragmentContainer, fragment)
                    .commit();
        }
    }
}