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This article will explain in detail how to use SwingWorker for you. The editor thinks it is very practical, so I share it with you as a reference. I hope you can get something after reading this article.

After JDK1.6, Swing provides a special class SwingWorker that can help you solve this programming paradigm. All you need to do is inherit this class, overload doInBackground, then call its execute method in actionPeformed, and update the interface through the publish/process method.

SwingWorker really just encapsulates the MyQueryTask in the example I mentioned earlier and considers it in more detail. The execute method is equivalent to the MyQuery Task thread start, which starts the background thread and returns immediately. SwingWorker can register PropertyChangeListener, and these listener are executed on the event dispatching thread, which is equivalent to the Runnable objects in MyQueryTask that access the component. In addition, publish and setProgress are just special property events, and process and done are just ways to respond to publish and PropertyChangeEvent.DONE events. So it's easy to change the above example to the SwingWorker version:

VoidmyButton_actionPerformed (ActionEventevt) {newMyQueryTask (). Execute ();} publicclassMyQueryTaskextendsSwingWorker {publicvoiddoInBackground () {/ query database finalResultSetresult=...; / / display record for (; result.next ();) {/ / add a row of data to the Model of the table and update the progress bar. Note that this is the access component publish (result);}. } publicvoidprocess (Object...result) {/ / add data jTable.add.... to the table / / Update the progress bar jProgress.setValue (....);}}

This is common for general time-consuming tasks, but there are some tasks that will be triggered periodically once triggered. How to deal with this task? JDK provides two Timer classes to help you complete scheduled tasks, one is javax.swing.Timer, one is java.util.Timer. The way to use them is simple, and for Swing's timer, use them as follows:

PublicvoidmyActionPerformed () {/ / suppose you click a button to start timing ActionmyAction=newAbstractAction () {publicvoidactionPerformed (ActionEvente) {/ / do periodic activities, such as displaying the current time Datedate=newDate (); jMyDate.setDate (date); / / jMyDate is a hypothetical component that can display date and time}}; newTimer (1000MMA Action). Start ();}

Java.util.Timer is similar, except that the action is encapsulated using TimerTask. Note that there is a key difference between the two Timer: the event handling of Swing's Timer is done on the event dispatching thread, so the operations in it can access the Swing component directly. The java.util.Timer may be on other threads, so SwingUtilities.invokeLater and invokeAndWait are used to access the component. Keep that in mind.

This is the end of the article on "how to use SwingWorker". I hope the above content can be of some help to you, so that you can learn more knowledge. if you think the article is good, please share it for more people to see.

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