net.sf.jguiraffe.examples.tutorial.bgtask

Class BgTaskCommand

java.lang.Object

net.sf.jguiraffe.gui.cmd.CommandBase

net.sf.jguiraffe.examples.tutorial.bgtask.BgTaskCommand

All Implemented Interfaces:

EventListener, FormActionListener, FormEventListener, Command

public class BgTaskCommand
extends CommandBase
implements FormActionListener

A command class for executing the background task.

This command class simulates the execution of a long-running background task. The execute() only sleeps a configurable number of seconds, but it demonstrates how an information dialog with a progress bar can be used to give the user feedback about the progress of the background task. This visual feedback is optional; it can be disabled, then the command only sleeps.

Version:

$Id: BgTaskCommand.java 205 2012-01-29 18:29:57Z oheger $

Author:

Oliver Heger

Constructor Summary

Constructors

Constructor and Description
BgTaskCommand(GUISynchronizer sync, Window infoWindow, BgTaskData taskData, ProgressBarHandler handler) Creates a new instance of BgTaskCommand and initializes it.

Method Summary

Modifier and Type	Method and Description
void	actionPerformed(FormActionEvent e) Notifies this object that the cancel button was pressed.
void	execute() Executes this command.
protected void	performGUIUpdate() Performs UI-related updates after the execution of the command.

Methods inherited from class net.sf.jguiraffe.gui.cmd.CommandBase

getException, getGUIUpdater, getLog, isUpdateGUI, onException, onFinally, setException

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

BgTaskCommand

public BgTaskCommand(GUISynchronizer sync,
                     Window infoWindow,
                     BgTaskData taskData,
                     ProgressBarHandler handler)

Creates a new instance of BgTaskCommand and initializes it.

Parameters:

sync - the GUISynchronizer

infoWindow - the reference to the information window

taskData - the data object with information about the background task

handler - the handler for the progress bar

Method Detail

actionPerformed

public void actionPerformed(FormActionEvent e)

Notifies this object that the cancel button was pressed. This method sets the cancel flag, so that the execution of the command is canceled.

Specified by:

actionPerformed in interface FormActionListener

Parameters:

e - the action event

execute

public void execute()
             throws Exception

Executes this command. Sleeps the specified number of seconds. If visual feedback is enabled, the progress bar is updated.

Specified by:

execute in interface Command

Throws:

Exception - if an error occurs

performGUIUpdate

protected void performGUIUpdate()

Performs UI-related updates after the execution of the command. This implementation closes the information window. Note that this method is only called if visual feedback is enabled.

Overrides:

performGUIUpdate in class CommandBase