Working With Multiple Views

The Multiple Document Interface (MDI), is an operating system feature that enables you to open more than one window to view a single file or document, or to open more than one file at a time.

In Gas Man, a single file or document corresponds to a single simulation. So, MDI allows Gas Man to have multiple views of multiple simulations open simultaneously. Although this may be confusing at first, it offers the Gas Man user some advantages in being able to display a wide range of information as densely as possible on the screen.

Recall that we described three view types (Control Panel, Picture, and Graph) earlier in the manual. By default, Gas Man will start a simulation with a single window containing tabs for each of the three types. You can view one tab at a time, by clicking on its title to select it. Gas Man starts with the Control Panel selected, as shown below.

Figure 2-5 shows a typical New (default) simulation with three tabs.

As you add views (Pictures and Graphs), Gas Man will create additional tabs. So, for example, if you add an additional Graph view to the simulation in Figure 2-5, another tab would appear beside ‘Graph1’ (called ‘Graph2’). Note that by opening multiple windows, you are getting multiple views of the same simulation, and that a view shows a particular perspective on the same simulation data shown in every other view. So you could, for example, have Graph1 scrolled to the first 5 minutes of induction, and show (scroll to) the last hour of the simulation in Graph2. Or, you could have Graph 1 be 5 hours wide and showing the entire course of anesthetic while Graph 2 shows the most recent 15 minutes.

Of course, it would be inconvenient to have a single, tabbed window if your aim were to compare the two graphs; you would have to alternately click on Graph1’s tab and Graph2’s tab

and you would not be able to view them simultaneously. To solve this problem, Gas Man allows you to create a separate window to hold Graph2 by dragging the tab for Graph2 to a different area on the desktop (away from its neighboring tabs). In general, you can drag any tab away to view it in its own window, and you can drag any tab between any two windows for the same simulation. (You cannot combine tabs from two simulations in one window.)

Remember, the view is just a representation. Closing a view (there is an ‘x’ in the upper right of each Picture and Graph tab to do just that) does not, for example, remove the anesthetic shown in the view from the experiment or simulation. If you do close a tab and you later want to recover it, just create a new Picture or Graph via the View menu.

The Control Panel, uniquely, is a ‘singleton.’ While you can create multiple Pictures and Graphs, there is exactly one Control Panel per open simulation, and closing the Control Panel is the same as closing the simulation.

If you get confused – running multiple simulations with multiple windows with multiple tabs of multiple anesthetics can get confusing in a hurry! – there is a helpful command in the Windows menu called Group Windows. This command will collect all the views for each open simulation into a single window.

As you might expect, Gas Man windows can be resized by dragging their edges and corners in or out. If you make a window too small to display its entire contents, scroll bars appear along the right and bottom edges. By moving the scroll button (the ‘thumb’), or clicking on the up, down, left, and right arrows, you can determine which portion of the Picture or Graph appears in the space you have for it on the screen. Therefore, especially if you have a small screen, you can use this feature to see and juxtapose different components of the simulation display without having to alternate between them.

Only one Gas Man window will appear to be active (in full-color and high-contrast) at any given time. Understanding which window is active is fairly intuitive – it is usually the last window to receive input or a mouse click, or it is the window most recently created. Gas Man uses the single active window to supply context, especially when there are multiple windows – that is, Gas Man interprets most commands (and shortcut keys) in the context of the active window. For example, the Close command will close the simulation viewed in the active window; the Print command prints the simulations shown in the active window, and so forth.