Multiple listboxes with different actions.

[Gintaras]

The example shows how to use functions and events for tasks like this.
Add another event LBN_SELCHANGE to execute code when listbox 3 selected. You can add it in Dialog Editor.
Use function LB_SelectedItem to get index of selected item in any listbox. Use id(your_listbox_id hDlg) instead of lParam.
Then use sel _i to execute different code depending on what is selected.