Inherited from UnityPlayerActivity to extend Android Platform.

MyUnityPlayerActivity.java

package com.kakaogames.android;

import android.os.Bundle;
import android.app.AlertDialog;
import android.content.DialogInterface;
import com.unity3d.player.UnityPlayerActivity;

public class MyUnityPlayerActivity extends UnityPlayerActivity
{
    @Override protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
    }

    @Override protected void onStart()
    {
        super.onStart();
        showTestDialog();
    }

    //test code
    private void showTestDialog() {
        AlertDialog.Builder builder = new AlertDialog.Builder(this);
        builder.setMessage("This is a test")
            .setCancelable(false)
            .setPositiveButton("Yes", new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int id) {
                    dialog.dismiss();
                }
            });
        AlertDialog alert = builder.create();
        alert.show();
    }
}