# LID Dialog Operations

To enter the LID's Define dialog, use the hand to double-click anywhere within the confines of the LID. Or, select the LID and choose Open Selection... from the Interface Menu. The LID Define dialog is shown in Figure 6-30. Define dialog operations are described in the text which follows.

Figure 6-30 List Input Device (LID) Define Dialog

Loading/Removing/Exchanging Variables: The Allowable and Selected lists, along with the buttons between the lists, are used to load, remove, and exchange the variables to be displayed in the LID page. All model variables (stocks, flows, converters) will appear in the Allowable list. Variables that you have loaded to the LID will appear in the Selected list. When a variable has been loaded to the Selected list, it will appear gray in the Allowable list. Here's how to move variables between the two lists:

- Loading Variables: To load a variable to the Selected list, double-click the variable name in the Allowable list. Or, select it, and click the >> button. To select multiple variables, simply drag-select or shift-click (for adjacent variables in the list), or control-click (Windows) or command-click (Macintosh) for noncontiguous variables.

Helpful Hint: If a variable is selected within the Selected list, any variables that you load to the selected list will be placed above the selected variable.

You can put as many variables as you want into a given list.

- Removing Variables: To remove a variable from the Selected list, select it. Then, click on the << button between the two lists. To select multiple variables, simply drag-select or shift-click for adjacent variables, or control-click (Windows) or command-click (Macintosh) for noncontiguous variables.

- Exchanging Variables: To exchange one or more variables in the Allowable list for one or more variables in the Selected list, select the desired variable(s) in each list. Then, click on the <-> button. The variables will be exchanged.

Setting the Range for LID Variables: Within the LID Define dialog, you should set the input range for any variable that has been loaded into the Selected . The input range will define the bounds of user input. The user will not be able to assign a value to the variable that is outside of the range that you have set. Setting the range is easy...

- Select variable in the selected list: Step 1 is to select the variable whose range you want to set from within the Selected list. When you do, the minimum and maximum values will appear in the Min and Max boxes next to the word "Range" in the dialog.

- Set the Range: In the Min and Max boxes, type the desired minimum and maximum values for the range of the variable. After entering these values, click the Set button. You're set!

Reset To: The Reset To check box is available when you have selected either a converter or flow in the selected list. As illustrated in Figure 6-30, when Reset to is checked, you can configure the selected variable to reset to a pre-determined value, either after one DT or after one time unit. Reset to is a great way to prevent users of your models from inadvertently repeating a decision (such as buying a factory) that is best thought of as a one-time event.

Show Navigation Arrow: When this is checked in the LID dialog, a navigation "down" arrow will appear on the LID surface, enabling the user to navigate from the LID to the corresponding model variable.

Formatting Options: As shown in Figure 6-30, the LID Pad Dialog provides you with three simple formatting options. Simply select a variable in the selected list, and check the desired options.

Adding Pages: At the bottom-left of the LID dialog is the apparatus for adding pages to the LID. Once you have loaded variables into the Selected list of the first page of the LID, the up-arrow in the apparatus will become active. Click on the arrow (next to the word "New") to create a new page. You can add as many pages to a Pad as you'd like. You can click on the up- or down-arrows to move between pages from within the dialog.

Titling a Page: To title a specific page of the LID, select the text in the Title field of the LID dialog. Then, type the desired title. The title will appear at the top of the LID.

Once you have configured a LID and hit OK, the LID will look something like what's shown in Figure 6-31:

Figure 6-31 Assigned List Input Device