Re: JFrame *sometimes* updating text on JLabel
Thanks for the comment. After further review of Swing, threads, and
the EDT, it was an issue with the EDT and how background tasks were
handled.
Initially, I created a Swing Timer to handle polling the server and put
the code to do that in an ActionListener. But after looking at this
article (http://www.javapractices.com/Topic160.cjp), I moved the server
polling code out of the ActionListener and instead created a daemon
thread to handle the polling.
*******Updated Code*********
public void startPollingTimer() {
timerBtwPolling = new Timer(pollingInterval, new
PollingListener());
timerBtwPolling.start();
}
private class PollingListener implements ActionListener {
public void actionPerformed(ActionEvent evt) {
Thread worker = new Thread( new PollingWorker() );
worker.setDaemon(true);
worker.start();
}
}
private class PollingWorker implements Runnable{
public void run(){
PollingController retriever = PollingController.getInstance();
retriever.startServerPolling();
}
}
*******Original Code*********
public void startPollingTimer() {
timerBtwPolling = new Timer(pollingInterval, new
PollingListener());
timerBtwPolling.start();
}
private class PollingListener implements ActionListener {
public void actionPerformed(ActionEvent evt) {
PollingController retriever = PollingController.getInstance();
retriever.startServerPolling();
}
}
private class PollingWorker implements Runnable{
public void run(){
PollingController retriever = PollingController.getInstance();
retriever.startRrtsPolling();
}
}
The code's not compilable, but hopefully the idea comes across. This
fix seems to have cleared up the EDT race conditions that were causing
the Message Pop-Up to sometimes show the updated text.
Andrew Thompson wrote:
mas2df wrote:
I am building an application that has the same functionality as Gmail
Notifier
What's that? (And how is the mention of it, relevant
to this this post?)
.. using Java Swing components. The application starts
...
The problem is that when the pop-up box appears, only *sometimes* does
the "connecting to server..." text appear on it, the other times, a
blank window shows up with no text.
I see no "connecting to server" text anywhere in the code
snippets you posted. The code is porbably blocking the EDT,
but it is hard to make further comments, without an SSCCE.
<http://www.physci.org/codes/sscce>
Andrew T.