Implementing ListView-Adapter in Android

This simple example creates

a new to-do list application using native Android View controls.Some of the features used

to create this application, includes ArrayAdapters, ListViews, and KeyListeners.

following files are required ,

1.java file(Activity)

2.main.xml

3.Another xml holding the textview.(in this ex: simple.xml)

Main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
    <EditText android:id="@+id/edittext"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:text="enter to add to the list"/>
 <ListView android:id="@+id/listView"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"/>
</LinearLayout>

Sample.xml

<?xml version="1.0" encoding="utf-8"?>

    <TextView  xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/text"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    />

import java.util.ArrayList;

import android.app.Activity;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.View;
import android.view.View.OnKeyListener;
import android.widget.ArrayAdapter;
import android.widget.EditText;
import android.widget.ListView;

public class to_do_list_activity extends Activity {

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

       //get reference to UI widgets
       final EditText text=(EditText) findViewById(R.id.edittext);
        ListView list=(ListView) findViewById(R.id.listView);

        //arraylist to store the items
        final ArrayList<string> al=new ArrayList<string>();

        // Create the array adapter to bind the array to the listview
        final ArrayAdapter<string> aa=new ArrayAdapter<string>(this, R.layout.simple, al);

       // Bind the array adapter to the listview.
        list.setAdapter(aa);
        text.setOnKeyListener(new OnKeyListener() {
  
  public boolean onKey(View v, int keyCode, KeyEvent event) {
   // TODO Auto-generated method stub
   
   if(event.getAction()==KeyEvent.ACTION_DOWN)
   if(keyCode==KeyEvent.KEYCODE_DPAD_CENTER) 
   {
   al.add(0,text.getText().toString());
   aa.notifyDataSetChanged();
   text.setText("");
   return true;
  }
   return false;
  }
 });
    }
}