The Process Hierarchy is shown on the top portion of the left panel of the Flow Chart view. This tool functions in the same way as the Process Hierarchy of the Navigator view. The Process Hierarchy displays a hierarchical list of process levels. It allows you to navigate the process easily and select the level which to be viewed in the flow chart on the right of the view. You can toggle its visibility by clicking the button.
The Process Hierarchy contains the Model Navigation toolbar with the Back and Forward buttons. These buttons provide a way to move between different states in the flow chart. Use these buttons to return to a previous process level, to use a previous zoom factor or to return to an original place after a peek at an earlier location.
Flow Chart view with Process Hierarchy and Preview (left side)