TrackControl is a toolbox call used in conjunction with CyberDEFs to handle text selection, auto-scrolling or highlighting...depending on which CDEF is parent to the CNTL (control).
Upon pushing down the mouse button within any item, you receive a "mousedown event." This is an ideal time to call TrackControl to handle all the appropriate behaviors of this particular mousedown occurence.
TextCDEFs selects a range of text as you click and drag—updating the scrollbar values as needed. Clicking the scroll bar of a CNTL (control) based on TextCDEF automatically moves the text view. Upon release of the mouse button, you receive a partcode indicating whether you let go inside of the scrollbar, inside of the text area or outside of the item.
Using TrackControl, PictCDEFs inverts, switches to another pict or just sits there on mousedown events. If you move the pointer in and out of the item as you continue to hold down the mouse button, your picture changes state accordingly—emulating the expected behavior of a radio, checkbox or standard button.
Like its fellow CyberDEFs, ListCDEFs responds to the call of TrackControl quite differently according to the Variation Codes set in your CNTL. If widget code has been added to the var code field, you can expect a widget to rotate, expand or collapsing on mousedowns occurring in its "widget zone." If you've added the check code to the var code, then a check mark toggles on and off when the check zone is clicked.
All of this with just ONE simple call to the toolbox: TrackControl.
