Bug 216811 [Markers] ExtendedMarkersView#setFocus doesn't
The result is that focus is lost if you drag the view to another stack... The most common implementation seems to be 'viewer.getControl().setFocus()... To test: select an element in the Problems or Tasks view. Drag the view to a new location (could be in an existing stack or a new one) notice that while the view is the active view the arrow keys don't navigate...
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/views/markers/ExtendedMarkersView.java
/*
			 * (non-Javadoc)
			 * 
			 * @see org.eclipse.jface.viewers.ITreeContentProvider#hasChildren(java.lang.Object)
			 */
			public boolean hasChildren(Object element) {
				return ((MarkerItem) element).getChildren().length > 0;
			}
			/*
			 * (non-Javadoc)
			 * 
			 * @see org.eclipse.jface.viewers.IContentProvider#inputChanged(org.eclipse.jface.viewers.Viewer,
			 *      java.lang.Object, java.lang.Object)
			 */
			public void inputChanged(Viewer viewer, Object oldInput,
					Object newInput) {
			}
		};
	}
	/**
	 * Return the listener that updates sort values on selection.
	 * 
	 * @return SelectionListener
	 */
	private SelectionListener getHeaderListener() {
		return new SelectionAdapter() {
			/**
			 * Handles the case of user selecting the header area.
			 */
			public void widgetSelected(SelectionEvent e) {