package rocks.inspectit.ui.rcp.view.util;
import org.eclipse.core.runtime.ListenerList;
import org.eclipse.jface.viewers.IPostSelectionProvider;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.jface.viewers.ISelectionChangedListener;
import org.eclipse.jface.viewers.ISelectionProvider;
import org.eclipse.jface.viewers.SelectionChangedEvent;
// NOCHKALL: Not our code.
/**
* IPostSelectionProvider implementation that delegates to another ISelectionProvider or
* IPostSelectionProvider. The selection provider used for delegation can be exchanged dynamically.
* Registered listeners are adjusted accordingly. This utility class may be used in workbench parts
* with multiple viewers.
* <p>
* <b>IMPORTANT:</b> The class code is copied/taken/based from <a href=
* "http://www.eclipse.org/articles/Article-WorkbenchSelections/SelectionProviderIntermediate.java"
* >Eclipse Workbench article</a>. Original author is Marc R. Hoffmann. License info can be found
* <a href="https://eclipse.org/legal/termsofuse.php">here</a>. Copied from
*
*
* @author Marc R. Hoffmann
*/
public class SelectionProviderIntermediate implements IPostSelectionProvider {
private final ListenerList selectionListeners = new ListenerList();
private final ListenerList postSelectionListeners = new ListenerList();
private ISelectionProvider delegate;
private ISelectionChangedListener selectionListener = new ISelectionChangedListener() {
@Override
public void selectionChanged(SelectionChangedEvent event) {
if (event.getSelectionProvider() == delegate) {
fireSelectionChanged(event.getSelection());
}
}
};
private ISelectionChangedListener postSelectionListener = new ISelectionChangedListener() {
@Override
public void selectionChanged(SelectionChangedEvent event) {
if (event.getSelectionProvider() == delegate) {
firePostSelectionChanged(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(ISelectionProvider newDelegate) {
if (delegate == newDelegate) { // NOPMD
return;
}
if (delegate != null) {
delegate.removeSelectionChangedListener(selectionListener);
if (delegate instanceof IPostSelectionProvider) {
((IPostSelectionProvider) delegate).removePostSelectionChangedListener(postSelectionListener);
}
}
delegate = newDelegate;
if (newDelegate != null) {
newDelegate.addSelectionChangedListener(selectionListener);
if (newDelegate instanceof IPostSelectionProvider) {
((IPostSelectionProvider) newDelegate).addPostSelectionChangedListener(postSelectionListener);
}
fireSelectionChanged(newDelegate.getSelection());
firePostSelectionChanged(newDelegate.getSelection());
}
}
protected void fireSelectionChanged(ISelection selection) {
fireSelectionChanged(selectionListeners, selection);
}
protected void firePostSelectionChanged(ISelection selection) {
fireSelectionChanged(postSelectionListeners, selection);
}
private void fireSelectionChanged(ListenerList list, ISelection selection) {
SelectionChangedEvent event = new SelectionChangedEvent(delegate, selection);
Object[] listeners = list.getListeners();
for (Object listener2 : listeners) {
ISelectionChangedListener listener = (ISelectionChangedListener) listener2;
listener.selectionChanged(event);
}
}
// IPostSelectionProvider Implementation
@Override
public void addSelectionChangedListener(ISelectionChangedListener listener) {
selectionListeners.add(listener);
}
@Override
public void removeSelectionChangedListener(ISelectionChangedListener listener) {
selectionListeners.remove(listener);
}
@Override
public void addPostSelectionChangedListener(ISelectionChangedListener listener) {
postSelectionListeners.add(listener);
}
@Override
public void removePostSelectionChangedListener(ISelectionChangedListener listener) {
postSelectionListeners.remove(listener);
}
@Override
public ISelection getSelection() {
return delegate == null ? null : delegate.getSelection();
}
@Override
public void setSelection(ISelection selection) {
if (delegate != null) {
delegate.setSelection(selection);
}
}
public ISelectionProvider getSelectionProviderDelegate() {
return delegate;
}
}