Tech I Enjoy Logo

Custom Search




  Home >> Miscellaneous
This article will try to cover aspects of creating Expandable List at runtime.
By "runtime", I mean to say not by using Android XML file for layout and Views 
but with the help of coding using Android API such as 
"android.app.ExpandableListActivity" 
"android.widget.BaseExpandableListAdapter"

After preparing/setting-up Software Environment for developing Mobile Application on 
Android Platform, for me initial task is to formulate idea as to how this application
is going to behave at run-time. For example I choose to use Expandable List View
for showing various categories/varieties of items within each group in form of List.

I choose to show "cup-boards" and "Cameras" as shopping items on display within this
ListView.On click of each item there will be sub/child elements/items getting 
displayed below the main selectable section/header.

Following images are going to show the actual screen that is expected at the time of
execution of this example source code:

Initial screen on invocation of this application:


On click/touch of the first category following image shows the sub-elements:


On click/touch of the second/subsequent category following image shows 
the sub-elements:


On click/touch of the both categories following image shows the sub-elements:


Let us go through the files used as far as this example is concerned:

Example Project on Android Platform main.xml file:
<?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">
    <ExpandableListView android:id="@android:id/list" 
              android:layout_width="fill_parent" 
              android:layout_height="fill_parent"
              android:background="#ffffff"/>
</LinearLayout>

ExpandableListViewExample.java
package com.techienjoy.example.expandablelistview;

import android.app.ExpandableListActivity;
import android.content.Context;
import android.graphics.Color;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseExpandableListAdapter;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TextView;

public class ExpandableListViewExample extends ExpandableListActivity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        setListAdapter(new ExampleAdapter(this));        
    }
    
    private class ExampleAdapter extends BaseExpandableListAdapter {
        private Context context;
    	public ExampleAdapter(Context context) {
    		this.context = context;
    	}
		@Override
		public Object getChild(int groupPosition, int childPosition) {
			return null;
		}
		@Override
		public long getChildId(int groupPosition, int childPosition) {
			return 0;
		}
		
		/**
		 *  getChildView overridden method will have responsibility of
		 *  constructing View for the child element when corresponding
		 *  group element is activated by click / touch action.
		 */
		 
		@Override
		public View getChildView(int groupPosition, int childPosition,
				boolean isLastChild, View convertView, ViewGroup parent) {
			LinearLayout linear = new LinearLayout(this.context);
			ImageView imView1 = null;
			ImageView imView2 = null;
			ImageView imView3 = null;
			ImageView imView4 = null;
			
			if(groupPosition == 0) {
				imView1 = new ImageView(this.context);
				imView1.setImageResource(R.drawable.cupboards1);
				imView2 = new ImageView(this.context);
				imView2.setImageResource(R.drawable.cupboards2);
				imView3 = new ImageView(this.context);
				imView3.setImageResource(R.drawable.cupboards3);
				imView4 = new ImageView(this.context);
				imView4.setImageResource(R.drawable.cupboards4);
			    
				linear.addView(imView1);
				linear.addView(imView2);
				linear.addView(imView3);
				linear.addView(imView4);				
			}
			if(groupPosition == 1) {
				imView1 = new ImageView(this.context);
				imView1.setImageResource(R.drawable.camera1);
				imView2 = new ImageView(this.context);
				imView2.setImageResource(R.drawable.camera2);
				imView3 = new ImageView(this.context);
				imView3.setImageResource(R.drawable.camera3);
				imView4 = new ImageView(this.context);
				imView4.setImageResource(R.drawable.camera4);
				
				linear.addView(imView1);
				linear.addView(imView2);
				linear.addView(imView3);
				linear.addView(imView4);				
			}
			return linear;
		}
		@Override
		public int getChildrenCount(int groupPosition) {
			return 1;
		}
		@Override
		public Object getGroup(int groupPosition) {
			return null;
		}
		@Override
		public int getGroupCount() {
			return 2;
		}
		@Override
		public long getGroupId(int groupPosition) {
			return 0;
		}
		@Override
		public View getGroupView(int groupPosition, boolean isExpanded,
				View convertView, ViewGroup parent) {
			LinearLayout linear = new LinearLayout(this.context);
			ImageView imView = null;
			if(groupPosition == 0) {
				TextView txtView = new TextView(this.context);
				txtView.setText("Cup Board :");
				txtView.setTextColor(Color.BLACK);
				linear.addView(txtView);
				imView = new ImageView(this.context);
				imView.setImageResource(R.drawable.cupboards);
				linear.addView(imView);
			}
			if(groupPosition == 1) {
				TextView txtView = new TextView(this.context);
				txtView.setText("Cameras :");
				txtView.setTextColor(Color.BLACK);
				linear.addView(txtView);
				imView = new ImageView(this.context);
				imView.setImageResource(R.drawable.camerascategory);
				linear.addView(imView);
			}
			return linear;
		}
		@Override
		public boolean hasStableIds() {
			return false;
		}
		@Override
		public boolean isChildSelectable(int groupPosition, 
				                         int childPosition) {
			return true;
		}
    }
}
If you would like to share your thoughts on this, please write to us @ usingframeworks @ gmail dot com If anything missed out , please let me know at techienjoy at yahoo . com
Android Image Gradient Merge :
Example using Images and Gradient Shape using
Android Platform.
Android Example on Expandable List :
Example on using Expandable ListView
on Android Platform.A step by step source code
explained.
Android ListView Example :
Example on Android ListView and
explained with a very simple scenario 
and article with appropriate screens 
captured and shown.
JSF example with source code :
JSF example of Tags and SelectBoxes 
with source code on Java Platform.
Web Load Test with example :
Example using Load test functionalities 
with code and explained
Android Example on Downloading AnyFormat :
Example on ways to download any file with
any format using Android Platform.
JSF example with source code :
JSF example of Tags and checkboxes 
with source code on Java Platform.
Android TimePickerDialog Example :
Example on Android TimePickerDialog
explained with a very simple scenario
and appropriate screens captured and shown.
Android Tab View Example :
Example on Android Tab View
explained with a very simple scenario
and appropriate screens captured and shown.
DOJO Dialog Example :
Example on using DOJO Dialog
explained with a very simple scenario
Android ListView Example :
Example on Android List View
explained with a very simple scenario 
and article with appropriate screens 
captured and shown.
JSF example with source code :
JSF example with source code on Java Platform.
Android Layout Example :
Android Example on using Layout
with source code Explained.
Android ListView Example :
Example on Android ListView 
explained with a very simple scenario
whereby showing folder and files with
structure and appropriate screens 
captured and shown.
JSF example with source code :
JSF example of Tags and Data Table 
with source code on Java Platform.
DOJO Tree Widget Example :
Example on using DOJO Tree Widget
explained with a very simple scenario
Android Gallery with SurfaceView :
Example showing Android Gallery
with SurfaceView and Spinner
Example of using Mule ESB JMS Transport :
Example of using Mule ESB JMS Transport with simple
to explain source code.
Example of using Log4J Part 1 :
Log4j example with source code on Java Platform.
Android Example on Expandable ListView :
Example on using Expandable ListView
on Android Platform.A step by step source code
explained.
Example of using Mule ESB File Transport :
Example of using Mule ESB File Transport with simple
to explain source code.
Android Examples :
List of ANDROid examples
with source code and output
screens captured and shown.
JSF example with source code :
JSF example of Tags and Code Walk-through 
with source code on Java Platform.
Using Different Logger Files :
Example on using different log files 
using Apache Log4j Framework.
Google GWT Example :
Example using GWT and some design patterns and various
ways of implementing this example.
Android ImageView Example :
Example on using ImageView using 
Android Platform. A very simple to setup
and see it working.
Wizard Framework using Java Platform :
Example using Custom Wizard Framework 
with code and explained
Example of using Log4J Part 2 :
Log4j example with source code on Java Platform.
Using Apache Commons Log With Example :
Example using Apache commons log 
with code and explained
Android Gallery Example :
Example on Android Gallery View
explained with a very simple scenario
and appropriate screens captured and shown.
Android Menu and MenuItem Example :
Example using Menu and MenuItem using Android Platform 
with code and explained
JSF example on Resource Bundle :
JSF example of Resource Bundle with source code 
on Java Platform.
Using Quartz Scheduler Example :
Example on how to use Quartz Scheduler.
JDBC Transaction Isolation Levels :
A short write-up on JDBC Transaction
Isolation showing ways to achieve
various Isolation levels using JDBC.
Example using Tag Library :
Example on how to code and use
Custom Tag Library on Java Platform.
List of Examples on Various Technologies :
List of Examples on Various Technologies and Frameworks.
Android Sensors Example :
Example on Android Sensors Listed and
explained with a very simple scenario 
and article with appropriate screens 
captured and shown.
Android Text to Speech Example :
Android Example on using Text
2 Speech conversion explained with
source code Explained.
Android Gallery Example Enhanced :
Example on Android Gallery View
explained with a very simple scenario
and appropriate screens captured and shown.
Android DatePickerDialog Example :
Example on Android DatePickerDialog
explained with a very simple scenario
and appropriate screens captured and shown.
JSF example on validation :
JSF Validation with example with source code 
on Java Platform.


References :
Tags: TabHost and TabActivity Example on Android Platform
Tags: ListView Example on Android Platform
Tags: android sensors list
Tags: android listview example
Tags: android imageview example
Tags: Android example download any file sourcecode
Tags: android expandable list dynamically created example
Tags: android expandable list example
Tags: Android Gallery surfaceviews spinner
Tags: Android example download any file sourcecode
Tags: Android Layout Example
Tags: Android Text To Speech Example

Tags: DOJO Example Dialog
Tags: DOJO Example Tree Widget
Tags: different logger file log4j
Tags: JDBC Transaction isolation
Tags: event handling java code
Tags: example quartz scheduler
Tags: example tag library web application
Tags: Flex
Tags: index
Tags: inmemory image creation java awt
Tags: JSF Example Main
Tags: JSF Example Tags CheckBoxes
Tags: JSF Example Tags dataTable
Tags: JSF Example Tags SelectBoxes
Tags: JSF Example Tags Walkthrough
Tags: JSF Example Validation
Tags: JSF Resource Bundle
Tags: log4j example 1
Tags: log4j example
Tags: Miscellaneous
Tags: Mule ESB File Transport
Tags: Mule ESB JMS Transport
Tags: stream download batch
Tags: sychronized block wait notify
Tags: thread wait notify example
Tags: using apache commons log
Tags: web load test
Tags: Wizard Framework Idea Java



DISCLAIMER :
The content provided in this page is not warranted and/or guaranteed by techienjoy.com. 
techienjoy.com is not liable for any negative consequences that may result/arise from 
implementing directly/indirectly any information covered in these pages/articles/tutorials.

All contents of this site is/are written and provided on an "AS IS" basis,
without WARRANTIES or conditions of any kind, either express or implied, including, without
limitation, merchantability, or fitness for a particular purpose. You are solely responsible
for determining the appropriateness of using or refering this and assume any risks associated
with this.

In spite of all precautions taken to avoid any typo in these pages, there might be some 
issues like grammatical mistakes and typos being observed in these pages, techienjoy.com
extends sincerest apologies to all our visitors for the same.



Android Examples || Android Examples

© Copyright 2010-2012, TECHIENJOY, All Rights Reserved.      Privacy Policy     Disclaimer & Terms & Conditions