MapInfo Pro Developers User Group

Hi,

After all this time I now have a requirement to pre-select items in a multi-list box - i.e set the initial selected items. I thought I could just loop though the number of items and set the value so if I had three items then I would do:-

for n = 1 to 3

    Alter control X value n

next

This does not work - it is just the last item that is selected.

Does anyone know how to do this?

Many thanks

Martin,

We do a similar thing and it seems to work ok.

The dialog handler calls a procedure that loops though an array of items pre selected and sets the value as you have done.

David

Hi Martin,

I am uncertain how to do this officially, but typically I'd use the LB_SETSEL win32 message if you're using a list box: https://msdn.microsoft.com/en-gb/library/ms909693.aspx . If you're using a list view I'd use the LVM_SETITEMSTATE  message instead: https://msdn.microsoft.com/en-us/library/ms930194.aspx

Thanks for the replies - I will have another go!?

Let us know how you get along, Martin.

The trick is to do the preselecting in the handler of the dialog.

You can find a sample of how to do this here: http://www.twiav.nl/php/mbsampleM.php#mlbx

Hi everyone - sorry I meant to update this. I did get it working and I was on the right path initially. My schoolboy error.. this was done as a part of a dialog rebuild and I had it set as a listbox!

oops 😳 ?