AbstractActivity.java

package com.recruit.app.ui.common;

import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.view.MenuItem;

import com.recruit.app.ui.Injector;
import com.recruit.app.ui.main.MainActivity;

import butterknife.Views;

import static android.content.Intent.FLAG_ACTIVITY_CLEAR_TOP;
import static android.content.Intent.FLAG_ACTIVITY_SINGLE_TOP;

/**
 * Base activity  which does not use fragments.
 */
public abstract class AbstractActivity extends ActionBarActivity {

    @Override
    protected void onCreate(final Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        Injector.inject(this);
    }

    @Override
    public void setContentView(final int layoutResId) {
        super.setContentView(layoutResId);

        // Used to inject views with the Butterknife library
        Views.inject(this);
    }

    @Override
    public boolean onOptionsItemSelected(final MenuItem item) {
        switch (item.getItemId()) {
            // This is the home button in the top left corner of the screen.
            case android.R.id.home:
                // Don't call finish! Because activity could have been started by an
                // outside activity and the home button would not operated as expected!
                final Intent homeIntent = new Intent(this, MainActivity.class);
                homeIntent.addFlags(FLAG_ACTIVITY_CLEAR_TOP | FLAG_ACTIVITY_SINGLE_TOP);
                startActivity(homeIntent);
                return true;
            default:
                return super.onOptionsItemSelected(item);
        }
    }
}