Adding a progressbar brings the browser to its knees (CPU Load)

[slibert]

Hello,

As stated in the thread https://vaadin.com/forum#!/thread/3433454 there is some high CPU load that kills the browser if you add a progressbar to a wizard's step.

Here is a snippet code :

private class FirstStep implements WizardStep, ProgressListener
{

    Label lblMessage;
    ProgressBar progress;

    RTWorker worker;
    boolean treatmentDone = false;

    @Override
    public String getCaption() {
        return "Simulation";
    }

    @Override
    public Component getContent() 
    {

        VerticalLayout vLayout = new VerticalLayout();
        vLayout.setWidth(100, Unit.PERCENTAGE);
        vLayout.setMargin(true);
        vLayout.setSpacing(true);

        try
        {

            /* Working Hard */
            worker = new RTWorker(); // Thread

            lblMessage = new Label("Working in progress... ");
            vLayout.addComponent(lblMessage);

            progress = new ProgressBar();
            progress.setVisible(true);
            progress.setWidth(500, Unit.PIXELS);
            progress.setHeight(60, Unit.PIXELS);
            progress.setIndeterminate(false);
            progress.setEnabled(true);
            app.setPollInterval(3000);

            vLayout.addComponent(progress);

}

As you can see, I put a really large poll interval, but still, when running, browser is barely responding to my actions.

Tested with last version of Wizard and Vaadin 7.4.3

Regards
Sebastien