Example: HelloWorld MIDlet

Note: The example described in this section is demonstrated using a development environment that includes Eclipse and S60 MIDP SDK Third Edition. The information also applies to the Series 40 SDK, even though that has not been used here. For more information on the recommended MIDP development environments, see the document MIDP project structure.

This section shows you how to create a HelloWorld example from scratch and run it with an emulator. The example creates a "Hello World!" message in a text box , which appears on the screen of your mobile device. The example illustrates the following functions:

Basic MIDlet life cycle
Use of high-level user interface components (using the TextBox class)
Simple command handling

Figure 12: HelloWorld MIDlet User Interface

The implementation of the example application consists of the following classes:

HelloWorldMIDlet.java, which represents the entry point of this application and creates the actual text to be shown in the text box.
HelloScreen.java, which creates an implementation of the TextBox class with three visual areas: a title, a string, and a command area. It also implements the CommandListener interface used to receive user input from the command area.