When you have several files open to edit, you can make the open file's editor the active editor each time the file is selected in the WorkSpace Navigator. If you link files to editors, when you select the editor, the file is selected in the WorkSpace Navigator and when you select the file in the WorkSpace Navigator, the editor selected.
To link a resource to its active editor:
Select the resource in the WorkSpace Navigator.
Do one of the following:
Right-click and select Open With|<editor name> from the context menu.
Click Link with Editor
on the main toolbar.