How to Create and Manipulate Multiple-Column List Boxes

• Microsoft Visual FoxPro for Windows, version 3.0

SUMMARY

This article discusses properties of multiple-column list or combo boxes, and describes how to create and manipulate them. All the tasks described require modifying the value of a property.

MORE INFORMATION

To build a multiple-column list or combo box, modify the ColumnCount property of the object to the number of columns that will be on the list.

Aligning Columns

Columns are aligned in a list box if one of the following conditions is met:

• The width of each column is explicitly written in the ColumnWidth property.

  -or-

• The font of the list is a monospaced font such as Courier New or Terminal. To change the font of the list, modify the FontName property.

Retrieving the Value of a List Item

Use the LIST property. When used in conjunction with the LISTITEMID, the LIST property can specify the value of a selected item in a row of columns. For example:

   List(Combo1.ListitemId,2)

Hiding a Column

To hide a column in a list, set the width of this column to 0 in the COLUMNWIDTH property. The COLUMNWIDTH property accepts a comma-delimited list of items, as in this example:

   CboCombo1.columnwidth="10,0,12"

Linking the Value of the Combo Box to Column N Only

Use the BOUNDCOLUMN property to link the value of a combo box to a column. The BOUNDCOLUMN property determines which column is bound to the value of a list box or combo box.

Linking the Selection to a Value that Is Not Displayed

To link the selection to a value not displayed, combine the previous two methods. The following steps illustrate this method using the Form Designer:

1. Create a form.

2. Right Click, and open the Data Environment. Add the CUSTOMER table from the SAMPLES\DATA directory.

3. Select the combo box control from the Form Controls toolbar, and drag it to the form. A combo box is created.

4. In the Property Sheet, select the Combo1 object from the Object drop-down, and modify the following properties:

   BoundColumn = 2 ColumnCount = 3 Columnwidth = 50,0,30 &&Under program control, Columnwidth= "50,0,30" RowSourceType= 6- Fields RowSource = Customer.contact,cust_id,company

5. Save the form as TEST, and run it. Only two columns are visible when the combo box is opened.

6. To verify that the value of the combo box is bound to the second column, type the following in the Debug window:

   TEST.Combo1.Value