Listbox Auto-Find by Erick Tejkowsi 12-05-02 Printer Version

When you use the REALbasic Listbox control, sometimes it's nice to offer an "auto-find" feature. As you press keys on the keyboard, the Listbox should attempt to locate any rows that display text that matches the pressed keys. The REALbasic Listbox doesn't perform this functionality, but it's not difficult to implement it yourself. This week we'll show you how.

Prep
capitals, states, currentkeys Launch REALbasic and open the Code Editor for the default window - Window1. Add three properties to the window by choosing Edit-New Property.

• LocateState(state as string)
• PopulateStates
• PopulateCapitals

Build the Interface
To create the interface for this project, open Window1 and add a Listbox, a Timer, and a StaticText control. Set the Timer's Period to 2000 in the Properties Window. Then, rearrange the various controls in the window to look like this.

Add the Code
To set things up, add the following code to the Open event of Listbox1.

Then, add the following code to the KeyDown event of the Listbox. This is where we track the keys that a users presses. As they press keys, we keep a running sequence of those keys. We also check to see if there is a match in the list using the LocateState method.

Next, add a little code to the Action event of Timer1. This resets the sequence of keypresses once every 2 seconds.

Finally, add the code for the three methods you created earlier. One method does the search for a match between keypresses and the Listbox contents. The other two methods populate the Listbox with state and capital names.

Conclusion
That's it for this week. As usual, you can download the completed project instead of typing it in. See you next week!