Mapping Commands : Event Command « J2ME « Java
Mapping Commands
/*--------------------------------------------------
* MappingCommands.java
*
* Example from the book: Core J2ME Technology
* Copyright John W. Muchow http://www.CoreJ2ME.com
* You may use/modify for any non-commercial purpose
*-------------------------------------------------*/
import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
public class MappingCommands extends MIDlet implements CommandListener
{
private Display display; // Reference to Display object for this MIDlet
private Form fmMain; // Main Form
private TextBox tbHelp; // Textbox to display help message
private Command cmExit; // Exit the MIDlet
private Command cmHelp; // Ask for Help
private Command cmBack; // Go "back" to the main form
public MappingCommands()
{
display = Display.getDisplay(this);
cmHelp = new Command("Help", Command.HELP, 1);
cmBack = new Command("Back", Command.BACK, 1);
cmExit = new Command("Exit", Command.EXIT, 1);
// Create the Form, add Commands, listen for events
fmMain = new Form("Core J2ME");
fmMain.addCommand(cmExit);
fmMain.addCommand(cmHelp);
fmMain.setCommandListener(this);
// Create the help Textbox with a maximum of 25 characters
tbHelp = new TextBox("Help", "Help text here...", 25, 0);
tbHelp.addCommand(cmBack);
tbHelp.setCommandListener(this);
}
// Called by application manager to start the MIDlet.
public void startApp()
{
display.setCurrent(fmMain);
}
// A required method
public void pauseApp()
{ }
// A required method
public void destroyApp(boolean unconditional)
{ }
// Process events
public void commandAction(Command c, Displayable s)
{
if (c == cmExit)
{
destroyApp(false);
notifyDestroyed();
}
else if (c == cmHelp)
display.setCurrent(tbHelp);
else if (c == cmBack)
display.setCurrent(fmMain);
}
}
