Unable to send EVT_COMMAND from one class to another - wxwidgets

I'm just starting with wxWidgets and I've run into a problem.
I have a mainwindow and another class derived from wxDialog. The main window launches the dialog box in non-modal mode. When the dialog closes, it posts an event but the handler for this event never gets called.
I'm using wxWidgets 3.1.5
The above two classes share a common header file, in which I have this code
wxDECLARE_EVENT(EVT_VISOR, wxCommandEvent);
This is my event table
BEGIN_EVENT_TABLE(VisorFrame, wxFrame)
....
EVT_COMMAND(ID_DlgDisplayLogsTerminated, EVT_VISOR, VisorFrame::OnDlgDisplayLogsTerinated)
....
END_EVENT_TABLE()
In the class derived from wxDialog, I have this at the top of my file
wxDEFINE_EVENT(EVT_VISOR, wxCommandEvent);
This is my event handler
void
VisorFrame::OnDlgDisplayLogsTerinated(wxCommandEvent& event)
{
wxPuts(_("VisorFrame::OnDlgDisplayLogsTerinated ent"));
}
And finally, this is how I post my event
void
DlgDisplayLogs::OnClose(wxCloseEvent& ev)
{
wxPuts(_("send event"));
wxCommandEvent event(EVT_VISOR, ID_DlgDisplayLogsTerminated); // enum value
event.SetEventObject(this);
event.SetString("Hello");
QueueEvent(event.Clone());
ev.Skip();
}
I have followed the documentation but I must be doing something wrong!

I think you're nearly there. I think what you could do is pass the wxFrame as a parent to your modeless dialog and post the event via the parent.
wxCommandEvent event(EVT_VISOR, ID_DlgDisplayLogsTerminated);
event.SetEventObject(this);
event.SetString("Hello");
wxPostEvent(frameParentPtr, event);
And in your wxFrame event table:
EVT_COMMAND(wxID_ANY, EVT_VISOR, VisorFrame::OnDlgDisplayLogsTerinated)

Related

Update Checked State of Handler in E4

In E3 we had a couple of handlers that were to be checked, and so the handler had to figure out when to be checked. Back then that was an easy task:
public class MyHandler extends AbstractHandler implements IElementUpdater {
#Override
public void updateElement(UIElement element, Map parameters) {
element.setChecked(calculateCheckState());
}
}
I found this similar question, but it's much broader (updating all commands, while I only want to set the checked state whenever the framework seems it necessary). Since tool and menu items can be check or radio items, this has to be possible somehow.
So how do I set the check state of a handler in E4?
You can set the check (selected) state in the #CanExecute method of the handler using something like:
#CanExecute
public boolean canExecute(MItem item)
{
item.setSelected(... checked state ....);
return true;
}
For a menu item the #CanExecute method is called every time the menu is displayed.
For a tool bar item you may need to use the IEventBroker UIEvents.REQUEST_ENABLEMENT_UPDATE_TOPIC event to force the method to run.
eventBroker.send(UIEvents.REQUEST_ENABLEMENT_UPDATE_TOPIC, argument);
argument can be
UIEvents.ALL_ELEMENT_ID to update all items.
The id of a single item to be updated.
A Selector (org.eclipse.e4.ui.workbench.Selector) to select the items to be updated.

JavaFX 8: How to automatically input a file on start-up?

I’m using JavaFX 8 and JDK 1.8.0_77 in IntelliJ with SceneBuilder. I created a basic pixel editor app. I have two windows(stages). One is a 32x128 matrix of Circle Objects placed in a Grid Pane and the other is a Message Center in Main.
You can see the Message Center window at: https://virtualartsite.wordpress.com/message-center/
I want to save messages using the Message Center app and scroll them on an RGB LED matrix that’s also 32x128. I save the messages in ArrayList<> of Message Objects and I write the ArrayList’s Message’s to a serialized file. I write the file calling writeObjArrayList () and input the file calling readObjArrayList().
I am able to write and read the file successfully and .add all the Message objects to the ArrayList on start-up so the user can edit or delete any message from the viewMessages ComboBox. BUT so far, I can only do so if I use a button event to call readObjArrayList(). This is the problem.
I want to read the file “behind the scenes”, when the app starts. I want to automatically read the file when the program starts up; the user shouldn’t have to click on a button.
My best idea was to use the following code which compiles but doesn’t appear to execute any code:
public void windowEvents(WindowEvent event){
if(event.getSource() == viewMessages) readObjArrayList();
}
I thought a WindowEvent would be fired with windowEvents=#OnShow for the ComboBox, viewMessages(FX:ID).
Please advise.
Thanks for your help.
According to the javadoc, the WindowEvent is related to Window showing/hiding actions. As Node classes aren't Windows, installing a WindowEvent handler on it won't have any effect.
Since you are using SceneBuilder, I assume that you must have an FXML file that has a fx:controller class defined. In any controller class, you can add a non-arg initialize() method which will be called right after the FXML file has been processed.
public class YourController {
#FXML
ComboBox viewMessages;
public void initialize() {
readObjArrayList();
}
private void readObjArrayList() {
...
}
}

Passing class objects as arguments in Windows 8 App and receive them on click event

The objects passed as arguments are only received an Navigation event. I want to receive them on Click Event,what should I use instead of Parameter??
void App1::MainPage::btuN_Click(Platform::Object^ sender, Windows::UI::Xaml::RoutedEventArgs^ e)
{
Variables^ data = (Variables^)e->OriginalSource;
if (data->sNotf!=nullptr)
Frame->Navigate(TypeName(BlankPage3::typeid), data);
}
I used OriginalSource, but it didn't work. Would any one help me? Thanks in Adv
OriginalSource property contains a reference to the object that raised the event. It has nothing to do with navigation parameters.
I'm not exactly sure which parameters you'd like to access in your button click event. The ones passed to your page in its navigation event? In this case you should handle said navigation event, retrieve the parameters there and store them into a private field of your page. In click event you can then read them back from the private field and pass them forward.
On a related note: passing non-basic types as navigation parameters is discouraged. If you need to do that, it's a better idea to just pass the object ids and read their values inside the page from a common repository.
When you navigate to your page, if the parameters from your navigation event are important, you should store them within your page object so it can be accessed later.
//MainPage needs to have a private Variables^ named Info
void MainPage::OnNavigatedTo(NavigationEventArgs^ e)
{
if(e->Parameter)
this->Info = dynamic_cast<Variables^>(e->Parameter);
}
And then access that variable from within your click handler:
void MainPage::btuN_Click(Platform::Object^ sender, Windows::UI::Xaml::RoutedEventArgs^ e)
{
if(this->Info)
if (this->Info->sNotf!=nullptr)
Frame->Navigate(TypeName(BlankPage3::typeid), Info);
}

How to make a propertysheetpage be a selection provider?

I've got a contributed command and a handler for it. The handler's execute event has to get the value for the property actually selected in the properties view and act on it, or to be disabled if no property selected.
I've tried:
1) Set the selection provider to something which provides selection from the property view. Something in this case is just PropertySheetViewer for my PropertySheetPage, but i can't set it as the selection provider because the PropertySheetPage's viewer is private and has no getter.
2) Overriding PropertySheetPage's createControl method: This method creates a Tree control for the PropertySheetViewer. A selection listener can be installed for that tree control, so maybe i can make my command handler implement SelectionListener... The solution would be somethin like:
In my editor:
public Object getAdapter(#SuppressWarnings("rawtypes") Class type) {
if (type == IPropertySheetPage.class) {
PropertySheetPage page = new PropertySheetPage() {
#Override
public void createControl(Composite parent) {
super.createControl(parent);
IHandler handler = someWayToGetMyCmdHandler();
((org.eclipse.swt.widgets.Tree) getControl())
.addSelectionListener(handler);
}
};
IPropertySheetEntry entry = new UndoablePropertySheetEntry(
getCommandStack());
page.setRootEntry(entry);
return page;
}
return super.getAdapter(type);
}
And my command handler implementing SelectionListener as i said... The problem with this approach is that i can't find a way to get a reference to my contributed command handler (someWayToGetMyCmdHandler() above).
Has anybody got any clue on this, or any other possible approach to the problem??
There's handleEntrySelection(ISelection selection) method in PropertySheetPage that you could override to be notified about selection changes in the viewer (although PropertySheetPage is #noextend).
The second part (updating the handler) is a bit more tricky than it would normally be. Commands/handlers get updated automatically when workbench selection changes (you just need to implement setEnabled(Object evaluationContext) AbstractHandler). But since PropertySheetPage is designed to change its input on global selection change, then you have to find some custom way to notify/update your handler.
As I understand, it is currently not possible to extend the platform command event handling mechanism with custom variables, so you just need to directly look up your handler using IHandlerService of the workbench.

Dynamic label of a popup action in eclipse plugin development

I want to create a simple eclipse plugin, which does: When you right click a java project, it will show a popup menu which has a item has label "N java files found in this project", where "N" is the file count.
I have an idea that I can update the label in "selectionChanged":
public class CountAction implements IObjectActionDelegate {
public void selectionChanged(IAction action, ISelection selection) {
action.setText(countJavaFiles());
}
}
But it doesn't work if I don't click that menu item, since the CountAction has not been loaded, that selectionChanged won't be invoked when you right-click on the project.
I have spent a lot of time on this, but not solved. Please help me.
An alternative to the article suggested by #kett_chup, is to use IElementUpdater. Simply
your handler must implement IElementUpdater
the handler.updateElement((UIElement element, Map parameters) must set the wanted text using element.setText("new text") - this new text will show up in menus and toolbars
whenever you need/want to update the command text use ICommandService.refreshElements(String commandId, Map filter) with your particular command ID - the global command service usually is just fine
The IElementUpdater interface can also be used to change the checked state - for commands with style=toggle - as well as the icons and the tool tip.
At last, I found a very easy way to implement this:
I don't need to change my code(the sample code in question), but I need to add a small startup class:
import org.eclipse.ui.IStartup;
public class MyStartUp implements IStartup {
#Override
public void earlyStartup() {
// Initial the action
new CountAction();
}
}
And add following to plugin.xml:
<extension
point="org.eclipse.ui.startup">
<startup
class="myplugin.MyStartUp">
</startup>
This MyStartUp will load an instance of that action at startup, then selectionChanged will be invoked each time when I right-click the projects or files.