I'm having a rare issue in my code, I have a method that makes a very simple validation based on a string variable:
private void showNextStep(String psCondition,String poStepName){
int liCurrentStep=Integer.valueOf(poStepName);
String lsNextTrueStep=moSteps[liCurrentStep][4];
String liNextFalseStep=moSteps[liCurrentStep][5];
if ("Yes".equals(psCondition)){
moFrmStepsContainer.getField(liNextFalseStep).hide();
moFrmStepsContainer.getField(lsNextTrueStep).show();
}else{
moFrmStepsContainer.getField(liNextFalseStep).show();
moFrmStepsContainer.getField(lsNextTrueStep).hide();
}
}
Now, here is the ticky part: if I execute the application without debugging mode, it does the validation right all the time, how ever if don't it always goes to the else block (or at least I think) I tried to use JS alerts (I have a class that calls JS methods) to debug manually and check the valors of the variables; the valors where all right and the validation was also good. This means that only debugging or putting alerts before at the beggining of the IF block it does the validation right, otherwise it always goes to the ELSE, what do you think it could be?
It might be worth mentioning this is a web application made in netbeans 6.9, using the framework GWT 2.1. This application runs in firefox 25.0.1
Thank you!
UPDATE
Here is the code of the event that calls my method
final ComboBoxItem loYesNo=new ComboBoxItem("cmbYesNo" + moSteps[liStepIndex][0],"");
loYesNo.setValueMap("Yes","No");
loYesNo.setVisible(false);
loYesNo.setAttribute("parent", liStepIndex);
loYesNo.addChangedHandler(new ChangedHandler() {
public void onChanged(ChangedEvent poEvent){
String lsStepName=loYesNo.getName();
FormItem loItem=moFrmStepsContainer.getField(lsStepName);
String liStepNumber=String.valueOf(loItem.getAttributeAsInt("parent"));
showNextStep((String)poEvent.getItem().getValue(),liStepNumber);
}
});
Related
I'm trying to use Casablanca to consume a REST api.
I've been following the microsoft tutorial, how ever i'm getting a crash and I cannot figure it out.
I'm using visual studio 2017 with C++11
I've codded a function GetRequest() that do work when used in a new empty project, but when I try to use it on my Project (Very big project with millions of code lines).
I'm crashing in the constructor of http_client, in the file xmemory0 line 118.
const uintptr_t _Ptr_container = _Ptr_user[-1];
This is a link to the callstack : https://i.imgur.com/lBm0Hv7.png
void RestManager::GetRequest()
{
auto fileStream = std::make_shared<ostream>();
// Open stream to output file.
pplx::task<void> requestTask = fstream::open_ostream(U("results.html")).then([=](ostream outFile)
{
*fileStream = outFile;
// Create http_client to send the request.
http_client client(U("XXX/XXX.svc/"));
// Build request URI and start the request.
uri_builder builder(U("/IsLive"));
builder.append_query(U("q"), U("cpprestsdk github"));
return client.request(methods::GET, builder.to_string());
})
// Handle response headers arriving.
.then([=](http_response response)
{
printf("Received response status code:%u\n", response.status_code());
// Write response body into the file.
return response.body().read_to_end(fileStream->streambuf());
})
// Close the file stream.
.then([=](size_t)
{
return fileStream->close();
});
// Wait for all the outstanding I/O to complete and handle any exceptions
try
{
requestTask.wait();
}
catch (const std::exception &e)
{
printf("Error exception:%s\n", e.what());
}
}
EDIT : I just want to add that the http_client constructor is the issue. It always crash inside it no matter what I send as parameter.
The wierd thing is that it's not crashing when i just make a main() that call this function.
I guess it must be due to some memory issues, however I have no idea how could I debug that.
Does anyone would have an idea about it?
Thanks and have a great day!
I've experienced a similar issue on ubuntu. It works in an empty project, but crashes randomly when put into an existing large project, complaining memory corruptions.
Turns out that the existing project loaded a proprietary library, which is using cpprestsdk (casablanca) internally. Even cpprestsdk is static linked, its symbols are still exported as Weak Symbols. So either my code crashes, or the proprietary library crashes.
Ideally, my project can be divided into several libraries, and load them with RTLD_LOCAL to avoid symbol clashes. But the proprietary library in my project only accept RTLD_GLOBAL, otherwise it crashes... So the import order and flags become important:
dlopen("my-lib-uses-cpprest", RTLD_LOCAL); //To avoid polluting the global
dlopen("proprietary-lib-with-built-in-cpprest", RTLD_GLOBAL); //In my case, this lib must be global
dlopen("another-lib-uses-cpprest", RTLD_DEEPBIND); //To avoid being affected by global
"it will probably never concern anyone."
I agree with that.
I guess this issues was very specific, and it will probably never concern anyone, but still I'm going to update on everything I found out about it.
On this project, we are using custom allocator, if i'm not wrong, it's not possible to give our custom allocator to this lib, which result to many random crash.
A good option to fix it would be to use the static version to this lib, however, since we are using a lot of dynamic lib, this option wasn't possible for us.
If you are on my case, I would advice to use the libcurl and rapidjson, it's a bit harder to use, but you can achieve the same goal.
I need assistance.
An issue with one of my endpoints timing out is causing me distress.
I did some performance tweaking with SQL and other REST services I am using but it only helps a little bit.
A nice solution for this problem, I thought, would be to use some of the Async capabilities of Spring Boot and Java 8 and perform some sort of "Fire and forget" action.
I tried something like that, but it is no good, the "Time to rock!" message gets printed out all right but it seems that getLyrics() method is not invoked at all!
//MyController.java
#GET
#Path("na/na/na")
#Produces({"application/json"})
public Response getLyrics() {
final String lyrics = delegate.getLyrics();
return Response.ok().entity(lyrics.isEmpty()).build();
}
//MyDelegate.java
#Async("threadPoolTaskExecutor")
public Future<Boolean> getLyrics() {
LOG.info("Time to rock!");
final boolean result = lyricsService.getLyrics();
return new AsyncResult<Boolean>(result);
}
//MyAsyncConfig.java
#Configuration
#EnableAsync
public class MyAsyncConfig {
#Bean(name = "threadPoolTaskExecutor")
public Executor threadPoolTaskExecutor() {
return new ThreadPoolTaskExecutor();
}
}
So, lyricsService.getLyrics() (that is not being called for some reason) does all the work, calls other services, fetches stuff from the SQL database, and performs calls against some other REST endpoints. All of this takes time and sometimes* causes a timeout. I would like it to process in peace, and if possible, return some sort of response when possible.
I tried several variations of this solution as it seems to be close to what I need, but can't seem to get why it is not working for me.
*often
I think, spring futures have to wait until operation is done. But java completable future is more powerful maybe you can try that.
Future<String> a = ...;
while(!a.isDone()){
}
here is a sample.
https://spring.io/guides/gs/async-method/
You may use Spring's DefferedResult, along with Java8's Computable future to make your controller non-blocking and thereby delegate the long running taks inside the Comupatable Future's whenAsync method.Here is a working example -
https://github.com/kazi-imran/TransactionStatistics
In my application I need to wait until external program (using QProcess) is finished. I want to keep the application responsible so blocking methods are unacceptable.
Also I need to disallow user input. I've tried to make QEventLoop and exec it with QEventLoop::ExcludeUserInputEvents flag, but as documentation says it only delays an event handling:
the events are not discarded; they will be delivered the next time processEvents() is called without the ExcludeUserInputEvents flag.
So I implemented simple event filter and install it on qApp (the idea is took from Qt Application: Simulating modal behaviour (enable/disable user input)). It works well, but sometimes QApplication::processEvents function never returns even if I specify the maximum timeout. Could anyone help me to understand for what reasons it periodically happens?
class UserInputEater : public QObject
{
public:
bool eventFilter(QObject *object, QEvent *event)
{
switch(event->type())
{
case QEvent::UpdateRequest:
case QEvent::UpdateLater:
case QEvent::Paint:
return QObject::eventFilter(object, event);
default:
return true;
}
}
};
-
UserInputEater eventEater;
qApp->installEventFilter(&eventEater);
QProcess prc;
prc.start("...");
while(!prc.waitForFinished(10))
{
if(qApp->hasPendingEvents())
{
// Sometimes it never returns from processEvents
qApp->processEvents(QEventLoop::AllEvents, 100);
}
}
qApp->removeEventFilter(&eventEater);
UPD: Seems like it depends of the timeout value for QProcess::waitForFinished.
I guess you are filtering some useful events (for example, QEvent::SockAct could be involved). Try to add some debug output and find out which event types you're actually filtering. Or it might be better to specify the black list of events you want to block instead of white list of events you want to allow. See this answer.
Also you shouldn't use return QObject::eventFilter(object, event);. You should use return false. All other event filters will be called automatically.
This solution however seems weird and unreasonable to me because you can just call setEnabled(false) for your top level widget to block user input, and then you can use QApplication::processEvents without any flags.
in the silverstripe backend I´m managing certain PageTypes via a ModelAdmin. That works fine so far, the only thing i can´t figure out is how to make a Page being "Published" when saving it.
Thats my code:
class ProjectPage extends Page {
public function onAfterWrite() {
$this->doPublish();
parent::onAfterWrite();
}
}
At the moment I can still see the ModelAdmin-created Pages in the Sitetree and I can see they are in Draft Mode. If I use the code above I get this error:
Maximum execution time of 30 seconds exceeded in
.../framework/model/DataList.php
Many thx,
Florian
the reason why you get "Maximum execution time exceeded" is because $this->doPublish(); calls $this->write(); which then calls $this->onAfterWrite();. And there you have your endless loop.
So doing this in onAfterWrite() or write() doesn't really work
you should just display the save & publish button instead of the save button
But I guess its easier said than done.
Well adding a button is actually just a few lines, but we also need a provide the functions that do what the button says it does.
This sounds like the perfect call for creating a new Module that allows proper handling of Pages in model admin. I have done this in SS2.4, and I have a pretty good idea of how to do it in SS3, but no time this week, poke me on the silverstripe irc channel on the weekend, maybe I have time on the weekend.
I found the same need/lack and I built a workaround that seems to work for me, maybe it can be useful.
public function onAfterWrite()
{
if(!$this->isPublished() || $this->getIsModifiedOnStage())
{
$this->publish('Stage', 'Live');
Controller::curr()->redirectBack();
}
parent::onAfterWrite();
}
Create a class that extends ModelAdmin and define an updateEditForm function to add a publish button to the actions in the GridFieldDetailForm component of the GridField.
public function updateEditForm($form) {
if ( ! singleton($this->owner->modelClass)->hasExtension('Versioned') ) return;
$gridField = $form->Fields()->fieldByName($this->owner->modelClass);
$gridField->getConfig()->getComponentByType('GridFieldDetailForm')->setItemEditFormCallback(function ($form) {
$form->Actions()->push(FormAction::create('doPublish', 'Save & Publish'));
});
}
Then create a class that extends GridFieldDetailForm_ItemRequest to provide an action handler for your publish button.
public function doPublish($data, $form) {
$return = $this->owner->doSave($data, $form);
$this->owner->record->publish('Stage', 'Live');
return $return;
}
Make sure the extensions are applied and you're done.
Or, you could just grab all the code you need from GitHub.
I've been looking at a view examples of the typical "raise dialog from viewmodel" problem, noting 3 main solutions:
use attached behaviors
use a mediator pattern
use a service
I'm getting a bit bogged down though and struggling to find a solution that easily fits into my problem space - which is a very simple file copy problem:
My viewmodel is processing a loop (copying a list of files)
When a file already exists at the destination I need to raise a modal dialog to get confirmation to replace
The vm needs to wait for and receive confirmation before continuing
The "modal dialog" is actually not a new window but a hidden overlay in my MainWindow, as per http://www.codeproject.com/KB/WPF/wpfmodaldialog.aspx (thanks Ronald!)
I'm mostly there but the biggest struggles I have are:
- how to pause the loop in the viewmodel while it waits for input
- how to get input back to the viewmodel within the loop so it can carry on
So far I'm leaning towards the service solution because it seems a direct method call with a return that the vm must wait for. However, it does mean the service needs to tie directly to the view in order to make an element visible?
If anyone can post some simple code that deals directly with this problem I (and the net) would be very happy! Thanks!
For example, you have a service called IDialogService with the following interface:
public interface IDialogService
{
bool ConfirmAction(string title, string confirmationText);
}
As you mentioned, in order for the service to be able to show the actual dialog it needs to have a reference to the view that will show the actual overlay element. But instead of directly referencing the view I prefer to reference it via an interface. Lets call it ICanShowDialog and it will have the following members:
public interface ICanShowDialog
{
void ShowDialog(object dialogContent);
void HideDialog();
}
This interface will be implemented by your view that owns the dialog overlay (e.g. your main window).
Now the interesting part: suspending the code execution while the dialog is shown. First of all, I would recommend you not to use overlay elements but use usual windows if possible. Then you will not have that problem. You can style the dialog window so it will look just like the overlay element.
Anyway, if you still want to use overlay elements then you can do the following trick to suspend the code execution:
Here is pseudo code of the ConfirmAction method of the IDialogService inteface:
public bool ConfirmAction(string title, string confirmationText)
{
ConfirmationDialogView dialogView = new ConfirmationDialogView(title, confirmationText);
DialogShower.ShowDialog(dialogView); // DialogShower is of type ICanShowDialog
while (!dialogView.ResultAvailable)
{
DispatcherUtils.DoEvents();
}
DialogShower.HideDialog();
return dialogView.Result;
}
Here is the code of DispatcherUtils.DoEvents() (that was taken from here: http://dedjo.blogspot.com/2007/08/how-to-doevents-in-wpf.html):
public static class DispatcherUtils
{
public static void DoEvents()
{
DispatcherFrame f = new DispatcherFrame();
Dispatcher.CurrentDispatcher.BeginInvoke(
DispatcherPriority.Background,
(SendOrPostCallback)delegate(object arg) {
DispatcherFrame fr = arg as DispatcherFrame;
fr.Continue=True;
}, f);
Dispatcher.PushFrame(frame);
}
}
But I must warn you. Using DoEvents can result in some subtle bugs caused by inner dispatcher loops.
As an alternative to suspending the code execution while a dialog is shown you can use callbacks:
public interface IDialogService
{
void ConfirmAction(string title, string confirmationText, Action<bool> dialogResultCallback);
}
But it will not be so convenient to use.