private boolean taskStart, taskSuccess, taskCancel, taskError;
public TestPage() {
AbstractTaskContainer taskContainer = DefaultTaskManager.getInstance().makeContainer(5L, TimeUnit.MINUTES);
form = new Form<Void>("form");
button = new ProgressButton("button", form, Model.of(taskContainer), this, Duration.milliseconds(300L)) {
@Override
protected void onTaskStart(AjaxRequestTarget ajaxRequestTarget) {