How to detect if content assist is open in a SourceViewer - eclipse

I am using a SourceViewer with a ContentAssistant configured like this:
public class MySourceViewerConfiguration extends TextSourceViewerConfiguration {
#Override
public IContentAssistant getContentAssistant(ISourceViewer sourceViewer) {
ContentAssistant assistant= new ContentAssistant();
...
return assistant;
}
}
SourceViewer sourceViewer = ...
sourceViewer.configure( new MySourceViewer() );
How can I determine if the content assist is currently active, i.e. if the proposal popup window is open?

There seems to be no way to query the SourceViewer directly whether the content assist is active.
However, if a completion listener is installed early enough before the SourceViewer is put into use, it can be used to track assist sessions.
For example:
class ContentAssistListener implements ICompletionListener {
boolean contentAssistActive;
#Override
public void assistSessionStarted( ContentAssistEvent event ) {
contentAssistActive = true;
}
#Override
public void assistSessionEnded( ContentAssistEvent event ) {
contentAssistActive = false;
}
#Override
public void selectionChanged( ICompletionProposal proposal, boolean smartToggle ) {
}
}
The contentAssistActive field will be true if the content assist is currently active and false otherwise.

Related

propertyChange not called when restoring default values

I am building a preference page extending the FieldEditorPreferencePage class.
This is the code (some obvious code not displayed):
public class PreferencePage extends FieldEditorPreferencePage implements IWorkbenchPreferencePage {
public static final String PREF_KEY_1 = "checkBoxPref";
public static final String PREF_KEY_2 = "filePref";
private FileFieldEditor pathField;
private BooleanFieldEditor yesOrNoField;
private Composite pathFieldParent;
#Override
public void init(IWorkbench workbench) {
setPreferenceStore(new ScopedPreferenceStore(InstanceScope.INSTANCE, Activator.PLUGIN_ID));
}
#Override
protected void createFieldEditors() {
this.yesOrNoField = new BooleanFieldEditor(PREF_KEY_1, "Check this box!", getFieldEditorParent());
this.pathFieldParent = getFieldEditorParent();
this.pathField = new FileFieldEditor(PREF_KEY_2, "Path:", this.pathFieldParent);
addField(this.yesOrNoField);
addField(this.pathField);
boolean isChecked = getPreferenceStore().getBoolean(PREF_KEY_1);
updatePathFieldEnablement(! isChecked);
}
/**
* Updates the fields according to entered values
*/
private void updatePathFieldEnablement(boolean enabled) {
this.pathField.setEnabled(enabled, this.pathFieldParent);
}
#SuppressWarnings("boxing")
#Override
public void propertyChange(PropertyChangeEvent event) {
if (event.getProperty().equals(FieldEditor.VALUE) && event.getSource() == this.yesOrNoField) {
updatePathFieldEnablement(! (boolean) event.getNewValue());
}
super.propertyChange(event);
}
}
The propertyChange method is there to enable/disable the FileFieldEditor depending on the BooleanFieldEditor value.
It works OK if I change the BooleanFieldEditor valeu by checking or unchecking it, but the propertyChange is not called when I hit the "Restore default values" button.
Do someone see a reason for that?
OK, I think I've got my response.
I went further in my investigation and I got to this code which seems suspect to me:
In class BooleanFieldEditor :
#Override
protected void doLoadDefault() {
if (checkBox != null) {
boolean value = getPreferenceStore().getDefaultBoolean(getPreferenceName());
checkBox.setSelection(value);
wasSelected = value;
}
}
and in class StringFieldEditor
#Override
protected void doLoadDefault() {
if (textField != null) {
String value = getPreferenceStore().getDefaultString(
getPreferenceName());
textField.setText(value);
}
valueChanged();
}
We can see that the FileFieldEditor (that inherits from StringFieldEditor) launches an PropertyChangeEvent to its listeners (valueChanged();) but not the BooleanFieldEditor. I did not find any code indicating that BooleanFieldEditor are using another mechanism. I think this is a bug in jFace.
To get around this problem, I just had to override the FieldEditorPreferencePage#performDefaults method and the result's fine.

How to enable content proposal in NatTable TextCellEditor?

I am currently looking for content assist feature in Nattable TextCellEditor.I have found the way to attach the ContentProposalAdapter and IContentProposalProvider by extending the Nattable TextCellEditor. but ,The selected value from the proposed list is not updating in the text control.
Snippet :
#Override
protected Text createEditorControl(final Composite parent, final int Style) {
this.textControl = super.createEditorControl(parent, style);
contentProposalAdapter =
new ContentProposalAdapter(this.textControl, new TextContentAdapter(), contentProposalProvider, keyStroke,
null);
contentProposalAdapter.addContentProposalListener(new IContentProposalListener() {
#Override
public void proposalAccepted(IContentProposal proposal) {
System.out.println(proposal.getContent());
}
});
}
The problem you have is the internal FocusListener that is triggered while selecting a value in the popup. To add the support you also need to override the internal FocusListener with a listener that doesn't fire if the content proposal popup is open.
An example would be to add a boolean flag that indicates that the popup is open and add a listener that sets the flag accordingly.
private boolean popupOpen = false;
...
contentProposalAdapter.addContentProposalListener(new IContentProposalListener2() {
#Override
public void proposalPopupClosed(ContentProposalAdapter adapter) {
this.popupOpen = false;
}
#Override
public void proposalPopupOpened(ContentProposalAdapter adapter) {
this.popupOpen = true;
}
});
And then implement and set a FocusListener in the constructor that takes care of that flag.
this.focusListener = new FocusAdapter() {
#Override
public void focusLost(FocusEvent e) {
if (!TextCellEditor.this.popupOpen) {
if (!commit(MoveDirectionEnum.NONE, true)) {
if (e.widget instanceof Control && !e.widget.isDisposed()) {
((Control) e.widget).forceFocus();
}
} else {
if (!TextCellEditor.this.parent.isDisposed())
TextCellEditor.this.parent.forceFocus();
}
}
}
};
In case the value should be immediately committed after it is selected, you need to add a listener that performs the commit after selection.
contentProposalAdapter.addContentProposalListener(new IContentProposalListener() {
#Override
public void proposalAccepted(IContentProposal proposal) {
commit(MoveDirectionEnum.NONE);
}
});
Unfortunately the AbstractCellEditor#InlineFocusListener is private and can therefore not be extended.
Feel free to file an enhancement ticket for NatTable to introduce the ability to easily add content proposals to a text cell editor.
https://bugs.eclipse.org/bugs/enter_bug.cgi?product=NatTable

Close Eclipse ViewPart tab when createPartControl function fails when launched from "Quick Access"?

The default behaviour when creating a new Eclipse ViewPart is to show the new tab regardless of what happens in the createPartControl function. For example, if didn't create anything, no widgets, nothing, a blank tab will be shown. I don't like this behaviour. I want to close that tab if initialization in createPartControl fails.
Now, I have a mouse-button-context-menu handler that can do this, e.g.
public class MyPartMB3Handler extends AbstractHandler {
#Override
public Object execute(final ExecutionEvent event)
throws ExecutionException {
// Create a view and show it.
IWorkbenchWindow window = HandlerUtil.getActiveWorkbenchWindow(event);
IWorkbenchPage page = window.getActivePage();
try {
MyPart viewPart = (MyPart)page.showView(MyPart.ID);
if(!viewPart.isCreated()) {
page.hideView(viewPart);
}
}
catch(PartInitException e) {
e.printStackTrace();
}
return null;
}
}
The isCreated function is a little hack that lets me know if my ViewPart initialization fails, e.g.
public class MyPart extends ViewPart {
public static final String ID = "com.myplugin.MyPart";
private Composite _parent = null;
#Override
public void createPartControl(Composite parent) {
if(!MyPlugin.createPartControl(parent) { // Some common part creation code I use.
//PlatformUI.getWorkbench().getActiveWorkbenchWindow().getActivePage().hideView(this);
return;
}
_parent = parent;
}
#Override
public void setFocus() {
}
public boolean isCreated() {
return _parent != null;
}
}
The problem arises when I launch this ViewPart from the Eclipse "Quick Access" field. I don't own the handler now. From an exception I forced, the handler might be org.eclipse.ui.internal.e4.compatibility.CompatibilityPart.createPartControl or org.eclipse.ui.internal.e4.compatibility.CompatibilityView.createPartControl or org.eclipse.ui.internal.e4.compatibility.CompatibilityPart.create.
I tried hiding the view inside the createPartControl function (see the commented line above), but Eclipse did not like that and spewed a pile of exceptions.
I thought maybe I could throw a PartInitException in createPartControl, but Eclipse tells me I'm not allowed to do that.
So, how do I get my menu handler behaviour when launching from "Quick Access"?
An underlying question might be, is there a better/proper way to achieve this behaviour?
You can close the view by running the hideView asynchronously after the createPartControl has finished - like this:
#Override
public void createPartControl(Composite parent) {
parent.getDisplay().asyncExec(new Runnable() {
#Override
public void run()
{
getSite().getPage().hideView(MyPart.this);
}
});

My selection listener doesn't seem to be registering properly

I am creating an Eclipse RCP application with multiple views. One of my views is a multi-page editor view. Each of those pages has a a master/details block. I need to register all of those TableViewers as selection providers for my other view to listen to.
After much research online, I came across this article about multiple selection providers in a single view. I followed the instructions to create this selection provider for multiple viewers.
class MyMultipleSelectionProvider implements ISelectionProvider {
private final ListenerList selectionListeners = new ListenerList();
private ISelectionProvider delegate;
private final ISelectionChangedListener selectionListener = new ISelectionChangedListener() {
#Override
public void selectionChanged(final SelectionChangedEvent event) {
if (event.getSelectionProvider() == AdaptabilityProfileSelectionProvider.this.delegate) {
fireSelectionChanged( event.getSelection() );
}
}
};
/**
* Sets a new selection provider to delegate to. Selection listeners
* registered with the previous delegate are removed before.
*
* #param newDelegate new selection provider
*/
public void setSelectionProviderDelegate(final ISelectionProvider newDelegate) {
if (this.delegate == newDelegate) {
return;
}
if (this.delegate != null) {
this.delegate.removeSelectionChangedListener(this.selectionListener);
}
this.delegate = newDelegate;
if (newDelegate != null) {
newDelegate.addSelectionChangedListener(this.selectionListener);
fireSelectionChanged(newDelegate.getSelection());
}
}
#Override
public void addSelectionChangedListener(final ISelectionChangedListener listener) {
this.selectionListeners.add(listener);
}
#Override
public ISelection getSelection() {
return this.delegate == null ? null : this.delegate.getSelection();
}
#Override
public void removeSelectionChangedListener(final ISelectionChangedListener listener) {
this.selectionListeners.remove(listener);
}
#Override
public void setSelection(final ISelection selection) {
if (this.delegate != null) {
this.delegate.setSelection(selection);
}
}
protected void fireSelectionChanged(final ISelection selection) {
fireSelectionChanged(this.selectionListeners, selection);
}
private void fireSelectionChanged(final ListenerList list, final ISelection selection) {
final SelectionChangedEvent event = new SelectionChangedEvent(this.delegate, selection);
final Object[] listeners = list.getListeners();
for (int i = 0; i < listeners.length; i++) {
final ISelectionChangedListener listener = (ISelectionChangedListener) listeners[i];
listener.selectionChanged(event);
}
}
}
I added a focusListener on all of the edior's viewers so they become the delegate:
tree.addFocusListener(new FocusAdapter() {
#Override
public void focusGained(final FocusEvent e) {
editor.getSelectionProvider().setSelectionProviderDelegate(MyEditorPage.this.treeViewer);
}
});
And I registered this as the selection provider for my editor:
site.setSelectionProvider( this.selectionProvider );
Then, within my view that needs to hear about the selection, I registered a selection listener for this editor:
getSite().getPage().addSelectionListener(MyEditor.ID, this.selectionListener);
When I run the application, I see that the delegate is being changed and the selection events are being fired. However, the listener list is empty.
I am never calling addSelectionChangeListener() directly. I was under the impression that that was what the selection service is for. Am I wrong? Should I be calling it? If so, when? If not, who is supposed to be adding the listener, and why isn't it happening?
If your code is based on FormEditor (or MultiPageEditorPart) then the selection provider is set to MultiPageSelectionProvider at the end of the init method. This may be overriding your site.setSelectionProvider call.
Using:
#Override
public void init(IEditorSite site, IEditorInput input)
throws PartInitException {
super.init(site, input);
site.setSelectionProvider(this.selectionProvider);
}
should make sure your provider is the one used.

Enable/Disbale eclispe rcp editor via menu when clicking on a TreeViewer element

In my eclipse RCP application I have a TreeViewer from where I can select different editors, for drawing elements, which show up after double clicking. In my top menu I have an option that allows to enable/disbale the drawing. The action for the editors looks like the following:
public class EnableEditorAction implements IEditorActionDelegate {
IEditor hallEditor = null;
#Override
public void run(IAction action) {
if (hallEditor != null){
hallEditor.setMachineHallEditMode(true);
}
}
#Override
public void setActiveEditor(IAction action, IEditorPart targetEditor) {
// check for enabled
boolean bEnabled = false;
if (targetEditor != null && targetEditor instanceof IMachineHallEditor) {
hallEditor = (IMachineHallEditor) targetEditor;
bEnabled = !hallEditor.isMachineHallEditingMode();
}
action.setEnabled(bEnabled);
}
#Override
public void selectionChanged(IAction action, ISelection selection) {
if (hallEditor != null) {
action.setEnabled(!hallEditor.isMachineHallEditingMode());
}
}
}
The problem I have is that the menu option is only enabled when clicking inside an editor. What i want is to enable the menu option also after clicking on one of the editors in the TreeViewer to the left.
How would I do that?
First, you don't need to check if targetEditor is null, since the action is already hooked to the editor via plugin.xml.
Second, I can see that you have an API isMachineHallEditingMode(). This should tell you if the left tree is selected, and the action should work properly.
It's important to set your action to always enabled in the plugin.xml. The Enables for: parameter should be empty, because enablement handling is done in your selectionChanged.
public class EnableEditorAction implements IEditorActionDelegate {
IEditor hallEditor;
#Override
public void run(IAction action) {
hallEditor.setMachineHallEditMode(true);
}
#Override
public void setActiveEditor(IAction action, IEditorPart targetEditor) {
hallEditor = (IMachineHallEditor) targetEditor;
}
#Override
public void selectionChanged(IAction action, ISelection selection) {
action.setEnabled(!hallEditor.isMachineHallEditingMode());
}
}