Hello,I am working on a Vampire panel which had generally no nav aids. But I have installed and developped a double instrument which switches from RMI to ILS when you click in the center of it. My problem is the way to make dynamic helps according the instrument represented. I know how to switch from one static text to another through a callback, but not from one dynamic text to another. For instance my helps on the button should be :- When in RMI mode : "Switch between VOR1 and VOR2 (actually VORx active)"- When in ILS mode : "Course selector (actual course XXX degrees)" Any help would be greatly appreciated to transfer the values in the X variables.In fact, I don't know two things:- How to concatenate two text strings- How to transfor a numeric value (the heading for instance) in a string to concatenateIf you can explain me, it's easy to make both strings in a callback which returns the right string according the gauge represented for the help.RegardsJean-Pierre

The functions you want are:strcpy, strcat, strncpy, and strncat.Start here:http://msdn.microsoft.com/library/default....2c_._mbscpy.aspDougEdit:Converting integers to strings:http://msdn2.microsoft.com/en-us/library/yakksftt.aspxConverting floats to strings:http://msdn.microsoft.com/library/default..../_crt__gcvt.asp

Thank you Doug for these informations.Best regardsJean-Pierre

Jean-Pierre,The ability to have a tooltip be dynamic is done this way:%ADF(%((L:ADFTrue,bool))%{if}Bearing True%{else}Bearing Relative%{end})This has the tooltip display "ADF Bearing True" or "ADF Bearing Relative" depending on an L-Var.Hope it helps.Scott / Vorlin