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Problems removing items from Listview Control

Started by mlwhitt, February 21, 2007, 04:21:51 PM

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mlwhitt

I have an application that I am trying to remove items from a Listview control but every time I use the deletestring command the program crashes on me.   I have been able to duplicate this with even a skeleton application with the same results.   Below is a sample code where I simply add two items to a listview control and then click a button and it is supposed to delete an item from the listview.  Instead the application just exist (crashes) without any warning.   Anyone have any ideas what I am doing wrong?

Def w1 as Window   

OpenWindow w1,0,0,600,710,@MINBOX|@MAXBOX|@SIZE,NULL,"Test",&main 
CONTROL w1,@BUTTON,"Poll",425,100,70,20,0x50000000,1 
CONTROL w1,@LISTBOX,"All",23,26,300,500,0x50B00148,5

addstring(w1,5,"Test 1")
addstring(w1,5,"Test 2")

WAITUNTIL w1 = 0   
END


SUB main
select @class
endselect


IF @CLASS = @IDCLOSEWINDOW
   CLOSEWINDOW w1
ENDIF

select @CONTROLID
   case 1    
     gosub dothis
endselect
RETURN
ENDSUB


sub dothis

deletestring W1,5,0
return
endsub

LarryMc

Your main routine is structured wrong.
The following version of your program works as expected.

   Def w1 as Window   

   OpenWindow w1,0,0,600,710,@MINBOX|@MAXBOX|@SIZE,NULL,"Test",&main 
   CONTROL w1,@BUTTON,"Poll",425,100,70,20,0x50000000,1 
   CONTROL w1,@LISTBOX,"All",23,26,300,500,0x50B00148,5

   addstring(w1,5,"Test 1")
   addstring(w1,5,"Test 2")

   WAITUNTIL w1 = 0   
   END


SUB main
   SELECT @MESSAGE
      CASE @IDCLOSEWINDOW
         CLOSEWINDOW w1
      case @IDCONTROL
         SELECT @CONTROLID
            case 1
               dothis()
         endselect
   endselect

   RETURN
ENDSUB


sub dothis()
   deletestring W1,5,0
   return
endsub
LarryMc
Larry McCaughn :)
Author of IWB+, Custom Button Designer library, Custom Chart Designer library, Snippet Manager, IWGrid control library, LM_Image control library

mlwhitt

Thanks I wasn't even paying attention to my sloppy code. ;)   After I fixed the structure it worked fine.  thanks again.

LarryMc

mlwhitt

You used "sloppy code" and "structure" in your replay.

There's a significant difference between the two.

Programs can still work even when the code is sloppy.
If the fundamental structure is wrong they typically never work.

Think of you program as a car.
You can't drive it without tires (a structual issue) but you can drive it with dirty tires(a sloppy issue).

Your program didn't work because of the structual issue. (The proper arrangement of the nested select statements.)

Just wanting to make sure you understand.  Not questioning your programming skill/experience. ;)

Larry
LarryMc
Larry McCaughn :)
Author of IWB+, Custom Button Designer library, Custom Chart Designer library, Snippet Manager, IWGrid control library, LM_Image control library