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
}
		MarkerItem[] children = markerItem.getChildren();
		for (int i = 0; i < children.length; i++) {
			addAllConcreteItems(children[i], allMarkers);
		}
	}
	/**
	 * Add the category to the list of expanded categories.
	 * 
	 * @param category
	 */
	void addExpandedCategory(MarkerCategory category) {
		getCategoriesToExpand().add(category.getName());
	}
	/**
	 * Add all of the markers in markerItem recursively.
	 * 
	 * @param markerItem
	 * @param allMarkers
	 *            {@link Collection} of {@link IMarker}
	 */
	private void addMarkers(MarkerItem markerItem, Collection allMarkers) {
		if (markerItem.getMarker() != null)
			allMarkers.add(markerItem.getMarker());
		MarkerItem[] children = markerItem.getChildren();
		for (int i = 0; i < children.length; i++) {
			addMarkers(children[i], allMarkers);
		}
	}
	/**