BaseActivity

package com.caioketo.owrpg;

/**
 * Created by Caio on 31/10/2014.
 */
import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.support.v7.widget.Toolbar;

public abstract class BaseActivity extends ActionBarActivity {

    private Toolbar toolbar;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(getLayoutResource());
        toolbar = (Toolbar) findViewById(R.id.toolbar);
        if (toolbar != null) {
            setSupportActionBar(toolbar);
            getSupportActionBar().setDisplayHomeAsUpEnabled(true);
        }
    }

    protected abstract int getLayoutResource();

    protected void setActionBarIcon(int iconRes) {
        toolbar.setNavigationIcon(iconRes);
    }
}

DiceActivity

package com.caioketo.owrpg;


import android.content.DialogInterface;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.widget.ImageView;

import com.cocosw.bottomsheet.BottomSheet;

import java.util.Random;

/**
 * Created by Caio on 31/10/2014.
 */
public class DiceActivity extends BaseActivity {
    private String strResult = "";
    private int intResult = 0;
    private final int[] MAX_DICES = {4, 6, 8, 10, 12, 20};
    private final int[] DICES_ICONS = {R.drawable.d4icon, R.drawable.d6icon, R.drawable.d8icon, R.drawable.d10icon,
            R.drawable.d12icon, R.drawable.d20icon};
    private final String[] DICES_NAMES = {"d4", "d6", "d8", "d10", "d12", "d20"};
    private int diceIndex = 0;
    private Random random = new Random();
    private ImageView imgDice;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        imgDice = (ImageView)findViewById(R.id.imgDice);
        findViewById(R.id.done).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                throwDice();
            }
        });
    }

    @Override
    protected int getLayoutResource() {
        return R.layout.activity_dice;
    }



    public void throwDice() {
        intResult = random.nextInt(MAX_DICES[diceIndex]) + 1;
        strResult = "You rolled " + Integer.toString(intResult) + " from a " + DICES_NAMES[diceIndex];
        done();
    }


    public void done() {
        Intent intent = new Intent();
        intent.putExtra("STR_RESULT", strResult);
        intent.putExtra("STR_RESULT", intResult);
        setResult(RESULT_OK, intent);
        finish();
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        new BottomSheet.Builder(this).sheet(R.menu.dices).listener(new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                switch (which) {
                    case R.id.d4:
                        diceIndex = 0;
                        break;
                    case R.id.d6:
                        diceIndex = 1;
                        break;
                    case R.id.d8:
                        diceIndex = 2;
                        break;
                    case R.id.d10:
                        diceIndex = 3;
                        break;
                    case R.id.d12:
                        diceIndex = 4;
                        break;
                    case R.id.d20:
                        diceIndex = 5;
                        break;
                }

                imgDice.setImageResource(DICES_ICONS[diceIndex]);
            }
        }).grid().show();
        return true;
    }
}

HomeActivity

package com.caioketo.owrpg;

import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Toast;

/**
 * Created by Caio on 31/10/2014.
 */
public class HomeActivity extends BaseActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        final Context ctx = this;

        findViewById(R.id.btn_dice).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Intent i = new Intent(ctx, DiceActivity.class);
                startActivityForResult(i, 0);
            }
        });
    }

    @Override
    protected int getLayoutResource() {
        return R.layout.home_activity;
    }

    @Override
    public void onActivityResult(int requestCode, int responseCode,
                                 Intent intent) {
        if (requestCode == 0) {
            if (responseCode == RESULT_OK) {
                String msg = intent.getExtras().getString("STR_RESULT", "ERRO");
                Toast.makeText(this, msg, Toast.LENGTH_SHORT).show();
            }
        }
    }
}