EmailListActivity.java

package com.ug.telescopio;

import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.HashMap;
import java.util.List;
import java.util.Locale;

import android.app.ListActivity;
import android.os.Bundle;
import android.util.Patterns;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.SimpleAdapter;
import android.widget.Toast;

public class EmailListActivity extends ListActivity implements OnClickListener{
	List<HashMap<String, String>> emails = new ArrayList<HashMap<String, String>>();
	public final static String EMAIL = "email";
	public final static String DATE_ADDED = "date";
	
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_email_list);
		
		Button btnAdd = (Button)findViewById(R.id.btnAdd);
		btnAdd.setOnClickListener(this);
		
		SimpleAdapter adapter = new SimpleAdapter(this, 
												  emails, 
												  android.R.layout.simple_list_item_2, 
												  new String[] {EMAIL, DATE_ADDED}, 
												  new int[] {android.R.id.text1, 
															 android.R.id.text2 });	
		setListAdapter(adapter);
	}

	@Override
	public void onClick(View v) {
		EditText editTextEmail = (EditText)findViewById(R.id.editTextEmail);
		String email = editTextEmail.getText().toString();
		
		if (!email.trim().equals("")) {
			if (Patterns.EMAIL_ADDRESS.matcher(email).matches()) {			
				HashMap<String, String> element = new HashMap<String, String>();
				String date = new SimpleDateFormat("dd/MM/yyyy HH:mm", 
											       Locale.getDefault())
															.format(Calendar.getInstance().getTime());
				element.put(EMAIL, email);
				element.put(DATE_ADDED, "agregado " + date);
				emails.add(element);
				
				final SimpleAdapter adapter = (SimpleAdapter) getListAdapter();
				adapter.notifyDataSetChanged();
			} else {
				Toast.makeText(getApplicationContext(), 
							   getResources().getString(R.string.txt_email_error), 
							   Toast.LENGTH_SHORT).show();
			}
		}
	}
}