The GWT timer I use in my application doesn't seem to respond to a call to cancel().
I see new server calls being fired, even after cancel() is reached.
com.google.gwt.user.client.Timer t = new com.google.gwt.user.client.Timer() {
#Override
public void run() {
myService.poll(result.getKey(), new HappyAsyncCallback<JobResult>() {
#Override
public void onSuccess(JobResult result) {
if (result.getUuid() != null && !result.getUuid().isEmpty()) {
Window.alert("Done! Cancelling...");
cancel();
}
}
});
}
};
t.scheduleRepeating(5000);
I read these similar issues, but haven't been able to use these issues to my advantage unfortunately.
GWT Timer cancel not working
Can't cancel repeat timer in GWT
I have been fooled by my own application here. We are doing a really lengthy batch process on the server and during this process the Timer will fire multiple calls to poll(). When the cancel() method is reached, these calls are still returning from the server :) Thanks for your suggestions, Manolo.
Related
I am using GWTBootstrap3 Typeahead widget. The main problem is the event is not getting deregistered and the events are bundling up as many times i load the component. The components are cached by default. The first component load triggers event 1 time and in second time component load triggers 2 times and so on. It's causing a lot of problem. I have tried HandlerRegistration and removeHandler() its not working. If any body found a solution please let me know.
Here is the bit of code where the event is registered:
HandlerRegistration typeAheadListener =
productSelect.addTypeaheadSelectedHandler(new TypeaheadSelectedHandler<Part>() {
#Override public void onSelected(TypeaheadSelectedEvent<Part> event) {
selectedPart = event.getSuggestion().getData(); // Handling the event
}
});
Thanks
I can think of two options there:
You can register the event handler in the productSelect's constructor, or in the code where you call the constructor. Not when the component is loaded.
You can check the HandlerRegistration API, it gives a tip on how a handler can deregister itself:
new MyHandler() {
HandlerRegistration reg = MyEvent.register(eventBus, this);
public void onMyThing(MyEvent event) {
/* do your thing * /
reg.removeHandler();
}
};
Is there a way to capture the event when a stage or screen gets focus? I tried to use focusedProperty but I guess that is used only when initially the stage/screen gets shown.
I am not sure if essentially I have to capture, WindowEvent.WINDOW_SHOWN event. I did try the following piece of code in my application, but there is probably a mistake.
stage.addEventFilter(WindowEvent.WINDOW_SHOWN, new EventHandler<WindowEvent>()
{
#Override
public void handle(WindowEvent window)
{
System.out.println("EventFilter :: Window shown");
}
});
stage.addEventHandler(WindowEvent.WINDOW_SHOWN, new EventHandler<WindowEvent>()
{
#Override
public void handle(WindowEvent window)
{
System.out.println("EventHandler :: Window shown");
}
});
None of the sysouts is shown when I execute the program.
Another part to the same problem is whether the event handler would get triggered if lets say I minimize and maximize the application(i.e the application again got focus) or I lock my machine and unlock it?
I have a working ProgressMonitorDialog, but I want to make sure that I am setting it up correctly.
First the Code:
Method to create Dialog
public void startProgressBar() {
try {
new ProgressMonitorDialog(getShell()).run(true, true,
new ProgressBarThread());
}
catch (InvocationTargetException e) {
MessageDialog.openError(getShell(), "Error", e.getMessage());
}
catch (InterruptedException e) {
MessageDialog.openInformation(getShell(), "Cancelled", e.getMessage());
}
}
Class File
class ProgressBarThread implements IRunnableWithProgress {
private static final int TOTAL_TIME = 1000;
public ProgressBarThread() {
}
public void run(IProgressMonitor monitor) throws InvocationTargetException,InterruptedException {
monitor.beginTask("Creating PDF File(s): Please wait.....", IProgressMonitor.UNKNOWN);
for (int total = 0; total < TOTAL_TIME ; total++) {
Thread.sleep(total);
monitor.worked(total);
if (total == TOTAL_TIME / 2) monitor.subTask("Please be patient... Operation should finish soon.");
}
monitor.done();
}
}
Method that calls the ProgressBar and runs a Pdf file creation Operation
private void startSavePdfOperation() {
Display.getDefault().asyncExec(new Runnable() {
public void run() {
startProgressBar();
}
});
saveOp = new AplotSaveOperation(appReg.getString("aplot.message.SAVETOPDF"), "PDF", session);
saveOp.addOperationListener(new MyOperationListener(this) {
public void endOperationImpl() {
java.io.File zipFile = null;
try {
AplotSaveResultsParser.SaveResult saveResults = saveOp.getSaveResults();
if (saveResults != null) {
ETC..... ETC......
Questions:
Being the ProgressMonitorDialog is a GUI, it needs to be executed in a
Display.getDefault().asyncExec?
If the ProgressMonitorDialog is running in a separate thread, how does it know to close when the operation is finsihed?
Is there any relationship between the progressbar and the operation?
I am correct in assuming that the for loop in the ProgressBarThread class is basically the timer that keeps the monitor open?
Is there a way to increase the speed of the ProgressMonitorDialog's indicator, also can you remove the cancel button?
This is what I am thinking is happening currently.
I am starting the progress bar just before I start the PDF Operation Listener
See startSavePdfOperation() Above
The progress bar is running as unknown, but using a for loop to keep the progress bar dialog open, while the operation is running on a thread in the background.
See Class ProgressBarThread above
When the PDF operation completes the listener operation class closes the base GUI dialog.
public void endOperation() {
try {
endOperationImpl();
}
finally {
Display.getDefault().asyncExec(new Runnable() {
public void run() {
w.getShell().setCursor(new Cursor(Display.getCurrent(), SWT.CURSOR_ARROW));
w.recursiveSetEnabled(getShell(), true);
w.getShell().setEnabled(!getShell().getEnabled());
w.close();
}
});
}
}
I am not sure what is happening to the ProgressBarThread monitor?
Is this Possible?
When the PDF Operation starts, the ProgressMonitorDialog opens and starts the indicator. OK with keeping it unknown.
When the PDF Operation completes, the monitor closes, then the base Dialog
I am just wanting to open progress bar dialog that will inform the user that their request is working in the background.
As stated the above code works, but I am afraid by letting the closing of Base GUI, destroy my Progress Thread and Monitor is not good practice.
First of all, in your ProgressBarThread#run() you should use monitor.worked(1). You don't need to set the total worked but increment it by the amount of work done, since the last time it was called.
Q1. Yes it needs to be executed in the display thread
Q2. Normally the work that needs to be done is actually performed in the runnable that is passed to the progress monitor dialog so that you can accurately report the amount of progress made. So your operation (if it is a synchronous call) should be called from within ProgressBarThread#run() so that you call monitor.worked(1) only when one file processing is complete.
Q3. What kind of operation are you running, perhaps it already supports showing progress bar, and you just need to invoke the right API. Is it an IUndoableOperation?
Q4. As I said this approach is problematic because you can never accurately report the progress and close the dialog only when the operation is completed. But if this is the only choice you have, then you can just save the monitor reference somewhere so that it is accessible to the other thread. Once monitor.done() is called, your ProgressBarThread#run() should return, the dialog will close.
Q5. You can remove the cancel button by passing the correct parameter to ProgressMonitorDialog#run(..):
new ProgressMonitorDialog(getShell()).run(true, false, new ProgressBarThread());
For the rest of the questions I can better answer if I know what kind of operation (what API) you are using.
I want to create a GWT application. That whenever the user gets logged in to system, it will show some information in PopUpPanel and after some time it gets disabled automatically.Is it possible with GWT ?
Could try something like:
Timer t = new Timer() {
#Override
public void run() {
popUpPanel.hide();
}
};
popUpPanel.show();
t.schedule(5000);
Where 5000 is how long you want to show the pop up for.
I'm attempting to create a bare bones app for use in developing a plugin. I don't need a workbench.
Below the title1 dialog will show, but the title2 never does.
What needs to be done in order for the 2nd one to be shown?
public class BareBonesApp extends AbstractApplication
{
public Object start(IApplicationContext context) throws Exception
{
Display display = PlatformUI.createDisplay();
MessageDialog.openWarning(null, "title1", "message1");
display.asyncExec(new Runnable()
{
public void run()
{
MessageDialog.openWarning(null, "title2", "message2");
}
});
return null;
}
}
Display has different queues for runnables that should run sync, async or in a specifc time (Display.timerExec). When Display.readAndDispatch has dispatched all events, first the runnables in the sync-queue are executed, then the async-queue is emptied and after that the due timerExec runnables are executed.
The only difference between Display.syncExec and Display.asyncExec is that the syncExec method waits for the runnable to be executed by the Display thread. Display.asyncExec simply queues the runnable and goes on.
So if "title2" never appears, I asume your application does not run the Display loop:
Display display = new Display(); // this thread should be the only one that creates a display instance
while (someCondition) {
if (!display.readAndDispatch())
display.sleep();
}