Skip to main content

By clicking Submit, you agree to the developerWorks terms of use.

The first time you sign into developerWorks, a profile is created for you. Select information in your developerWorks profile is displayed to the public, but you may edit the information at any time. Your first name, last name (unless you choose to hide them), and display name will accompany the content that you post.

All information submitted is secure.

  • Close [x]

The first time you sign in to developerWorks, a profile is created for you, so you need to choose a display name. Your display name accompanies the content you post on developerworks.

Please choose a display name between 3-31 characters. Your display name must be unique in the developerWorks community and should not be your email address for privacy reasons.

By clicking Submit, you agree to the developerWorks terms of use.

All information submitted is secure.

  • Close [x]

Downloading images in J2ME

John Muchow, Freelance Technical Writer
John Muchow, a freelance technical writer and recruiter, is the author of Core J2ME Technology and MIDP. Visit Core J2ME for additional source code, articles, and developer resources. Send John e-mail for additional information about writing projects or technical recruiting.

Summary:  This tutorial demonstrates how to download and display images with J2ME (Java 2 Micro Edition) and the Mobile Information Device Profile (MIDP).

Date:  07 Oct 2003
Level:  Introductory PDF:  A4 and Letter (582 KB | 38 pages)Get Adobe® Reader®

Activity:  3991 views
Comments:  

Before you start

About this tutorial

This tutorial demonstrates how to download and display images with J2ME (Java 2 Micro Edition) and the Mobile Information Device Profile (MIDP).

I'll walk through creating two J2ME applications, each showing how to open a network connection to a remote server, and download and display an image. The first application is bare-bones, with no frills. I'll build upon this application in the second example to add support for downloading of images in a background thread and providing consistent messages to the user to indicate the current status of the application.

By the end of this tutorial you see just how easy it is to begin writing network-aware applications with J2ME.

Prerequisites

You'll need two software tools to complete this tutorial:

  • The Java Development Kit (JDK): The JDK provides the Java source code compiler and a utility to create Java Archive (JAR) files. When working with version 2.0 of the Wireless Toolkit (as I will be here), you'll need to download JDK version 1.4 or greater. Download JDK version 1.4.1.
  • The Wireless Toolkit (WTK): The Sun Microsystems Wireless Toolkit (WTK) is an integrated development environment (IDE) for creating Java 2 Platform, Micro Edition (J2ME) MIDlets. The WTK download contains an IDE, as well as the libraries required for creating MIDlets. Download J2ME Wireless Toolkit 2.0.

Install the software

The Java Development Kit (JDK)
Use the JDK documentation to install the JDK. You can choose either the default directory or specify another directory. If you choose to specify a directory, make a note of where you install the JDK. During the installation process for the Wireless Toolkit, the software attempts to locate the Java Virtual Machine (JVM); if it cannot locate the JVM, you are prompted for the JDK installation path.

The Wireless Toolkit (WTK)
This tutorial builds on an earlier developerWorks tutorial "MIDlet Development with the Wireless Toolkit" (see Resources), which explains the basics of creating MIDlets with the toolkit. This tutorial is an excellent starting point if you are new to the Wireless Toolkit.

The Wireless Toolkit is contained within a single executable file. Run this file to begin the installation process. It is recommended that you use the default installation directory. However, if you do not use the default directory, make sure the path you select does not include any spaces.

1 of 7 | Next

Comments



Help: Update or add to My dW interests

What's this?

This little timesaver lets you update your My developerWorks profile with just one click! The general subject of this content (AIX and UNIX, Information Management, Lotus, Rational, Tivoli, WebSphere, Java, Linux, Open source, SOA and Web services, Web development, or XML) will be added to the interests section of your profile, if it's not there already. You only need to be logged in to My developerWorks.

And what's the point of adding your interests to your profile? That's how you find other users with the same interests as yours, and see what they're reading and contributing to the community. Your interests also help us recommend relevant developerWorks content to you.

View your My developerWorks profile

Return from help

Help: Remove from My dW interests

What's this?

Removing this interest does not alter your profile, but rather removes this piece of content from a list of all content for which you've indicated interest. In a future enhancement to My developerWorks, you'll be able to see a record of that content.

View your My developerWorks profile

Return from help

static.content.url=http://www.ibm.com/developerworks/js/artrating/
SITE_ID=1
Zone=Java technology
ArticleID=137020
TutorialTitle=Downloading images in J2ME
publish-date=10072003
author1-email=
author1-email-cc=

Tags

Help
Use the search field to find all types of content in My developerWorks with that tag.

Use the slider bar to see more or fewer tags.

Popular tags shows the top tags for this particular content zone (for example, Java technology, Linux, WebSphere).

My tags shows your tags for this particular content zone (for example, Java technology, Linux, WebSphere).

Use the search field to find all types of content in My developerWorks with that tag. Popular tags shows the top tags for this particular content zone (for example, Java technology, Linux, WebSphere). My tags shows your tags for this particular content zone (for example, Java technology, Linux, WebSphere).