The main window allows exploring the system of any GDB component having shown elements of this structure in the right pane. However, it is not possible to show two components simultaneously and that is why it is difficult to make a comparison: one has to switch from one component to the other. To show the structure of several components on the screen simultaneously the command Window+New window can be used. This command opens a navigation window similar to the main one, it contains the same elements list that is shown in the right pane of the main window at this time. When this additional navigation window is opened it has no hierarchic pane, however, such a pane can be created by the command View+Hierarchy. So, additional navigation windows differ from the main one only in two aspects:
GDB menu for additional navigation windows contains only the item Print. All operations with GDB as a whole are performed using GDB menu of the main window.
Additional navigation windows can be closed at any time, but closing of the main window will cause ObjectLand session termination.
During further moving along the tree structure the contents of the main window panes changes, but it will not affect other opened navigation windows because these windows are independent. However, if in any of these windows operations changing something in GDB structure (for example, adding a new feature type or removing a table, etc.) are performed, then those windows in which the corresponding structure elements are displayed will be redrawn to display the changes.
At figure 4-5 the screen view is shown when apart from the main window, navigation windows showing the structure of two tables and one theme are opened.
Figure 4-5. Main window and additional navigation windows
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