Tuesday, 20 November 2012

Android ListView Tutorial

A ListView is a ViewGroup which displays a list of items  can scrollable.The list items can are inserted automatically onto the list using a ListAdapter.

In this tutorial,i'm going to teach you creating a ListView and showing a toast message on the selected list item.

Step by step tutorial:

1.Create a new project

       Project Name    :  SimpleListView
             Package              :  com.roney.simplelistview
             Main Activity     :  SimpleListViewActivity.java
             Build Target       :  Android 2.2

2.After creating the project,Open your MAinActivity class.Here it is 
    SimpleListViewActivity.java and extends the class from ListActivity. 

  public class SimpleListViewActivity extends ListActivity


3.Now we nee to have a string resource file to store all list items.So  
    create  a   XML file under res/values/ folder and save it as list_data.xml 
    and enter the following code.

<?xml version="1.0" encoding="utf-8"?>
    <string-array name="social_sites">

4.Now we need to create the layout to show each items in the ListView. 
    Create a xml file under res/layout folder as list_item.xml

<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
        android:textStyle="bold" >

5.Open your main activity,ie.SimpleListViewActivity.java and type the 
    following code.


package com.roney.simplelistview;

import android.app.ListActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.Toast;

public class SimpleListViewActivity extends ListActivity
 // defining array to store string resources
 String[] social_sites;
 public void onCreate(Bundle savedInstanceState)

 // storing string resources into Array
 social_sites = getResources().getStringArray(R.array.social_sites);
 // Binding resources Array to ListAdapter
 this.setListAdapter(new ArrayAdapter<String>
(this,R.layout.list_item, R.id.label,social_sites));

protected void onListItemClick(ListView l, View v, int position, long id)
      Toast.makeText(this, "You have selected : "+social_sites[position], Toast.LENGTH_SHORT).show();

6.Now its time to run the project.The result will show in the emulator is 
    shown bellow.

  The result show a ListView with list of array items.When a item in the list is selected you will see a toast message.

"Your comments and suggestions please"