Problems with Combobox

[Bern Ertl]

Please help! I cannot get my program to recognize text input from the user into the text box of a combobox. Here's my code:

#COMPILE EXE
#INCLUDE "DDT.INC"
$REGISTER NONE

%IDOK = 1
%IDCANCEL = 2
%IDUSER = 3
%BS_DEFAULT = 1

'------------------------------------------------------------------------------
' Global variable to recieve the user name

GLOBAL ComboText$

'------------------------------------------------------------------------------

CALLBACK FUNCTION OkButton()

COMBOBOX GET TEXT CBHNDL, %IDUSER TO ComboText$
DIALOG END CBHNDL, 1

END FUNCTION

CALLBACK FUNCTION CancelButton()

DIALOG END CBHNDL, 0

END FUNCTION

FUNCTION DoIt&()

LOCAL hDlg&, Result&

' ** Create a new dialog template
DIALOG NEW 0, "ComboBox Test", ,, 200, 82, 0, 0 TO hDlg&

' ** Add controls to it
CONTROL ADD LABEL, hDlg&, -1, "&User Name", 14, 14, 36, 12,
CONTROL ADD COMBOBOX, hDlg&, %IDUSER, , 60, 12, 120, 100, %CBS_DROPDOWN OR %WS_VSCROLL OR %WS_TABSTOP OR %CBS_HASSTRINGS
CONTROL ADD BUTTON, hDlg&, %IDOK, "&OK", 34, 60, 40, 14, %BS_DEFAULT CALL OkButton
CONTROL ADD BUTTON, hDlg&, %IDCANCEL,"&Cancel", 124, 60, 40, 14, 0 CALL CancelButton

' Clear the combo box list
COMBOBOX RESET hDlg&, %IDUSER
COMBOBOX ADD hDlg&, %IDUSER, "Joe Blow"
COMBOBOX ADD hDlg&, %IDUSER, "John Doe"

' ** Display the dialog
DIALOG SHOW MODAL hDlg& TO Result&

FUNCTION = Result&

END FUNCTION

'------------------------------------------------------------------------------

FUNCTION PBMAIN () AS LONG

IF DoIt&() THEN MSGBOX ">"+ComboText$+"<"

END FUNCTION

[Borje Hagsten]

Try CONTROL GET TEXT.. instead of COMBOBOX.. and it will work.


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[Bern Ertl]

Thank you! Wow that was fast!

I'm able to continue with my code now.

Note to PB: Why doesn't the COMBOBOX GET TEXT statement work? If CONTROL GET TEXT has the exact same functionality, why include it at all?

Thanks again for the super fast problem solving....


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[Semen Matusovski]

I always thought that american guys have problems with English.

From Pb.Hlp

COMBOBOX GET TEXT hDlg&, id& TO text$
Retrieves the default text from a combo box.

The default selection can be done
a) by COMBOBOX SELECT hDlg&, id&, pos&
b) by selecing an item from the list in run-time

If to type something in textbox - nothing selected.

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E-MAIL: [email protected]

[Borje Hagsten]

The combo listbox is exactly what it says, a combination of a
listbox and an edit control. That is why there are two different
sets of commands for it, so to speak.

CONTROL GET TEXT is most likely a wrapper for two SendMessage calls,
WM_GETTEXTLENGTH and WM_GETTEXT, which also can be used.

Same thing with COMBOBOX GET TEXT, which I guess is a wrapper for
the CB_GETCURSEL and CB_GETLBTEXT messages.

The PB helpfile isn't very clear on this. Like Semen pointed out,
it only tells us it "retieves the default text", whatever that
means. "Selected item's text" would have been better, IMHO..

A good tip. In Win32api.hlp all controls are explained. If you
for example look up "Combo Boxes" and then use the Right Arrow
button to turn pages, there are a lot of useful info about it
there, including description on how to do ownerdrawn and
subclassed controls, etc. Lots of useful info there.


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[This message has been edited by Borje Hagsten (edited January 17, 2001).]

[Bern Ertl]

Da Semen, I read that ("DEFAULT") in the docs, but I did not understand what it meant. It is not explained. As this is all new to me, I assumed that it meant whatever was in the text box.

What would be the purpose of checking for the default assuming it wasn't already known when (it seems to me) the actual (user) selection is really what one is interested in?

Thanks again,
Bernard Ertl

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[Lance Edmonds]

In the majority of cases, retrieving the text in the edit control portion of the combobox is all that is often required, however, retrieving the default text could be useful for assisting in statusbar information as selections are made, or in a whole host of other situations like reading information from a child dialog, etc. When it comes to using control's, there is nothing more creative and inventive than a GUI programmer who wants to add a "twist" to their app's GUI interface.

Anyway, this has been an interesting thread... I'll be asking the Documentation Dept to clarify the relevent text in the next update to the documentation.

Thanks for pointing it out!

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Lance
PowerBASIC Support
mailto:[email protected][email protected]</A>

[Bern Ertl]

Lance,

While you are at it, could you put in a request to the Docs Dept. to include the "See also" section which they included in the PB 3.x (DOS) docs? I found them indispensible when I couldn't remember the exact function/sub I was looking for. For the new DDT functions, a section like that would definately help (me at least).

Thanks.

Bernard Ertl

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[Scott Turchin]

Just for GP, I was peruzing a piece of code of mine that uses the combo box extensively and found that ComboBox GetText does in fact work...weird.

        Case %IDCOMBOBOX
              If LoWrd(CbCtlMsg) = %CBN_SELENDOK Then
                   ComboBox Get Text hDlg ,%IDCOMBOBOX To g_szDestURL 'Destination URL
                   Array Scan HistArray(1), = g_szDestURL, To HistIndex 'Get index # for history file
                   ComboBox Select hDlg, %IDCOMBOBOX, HistIndex 'Now select it manually to make it show
                   g_Result = ShellExecute(ByVal %NULL, "open", g_szDestURL + Chr$(0), ByVal %NULL, ByVal %NULL,%SW_SHOWMAXIMIZED) 'Now launch the URL
               End If
               Function = 1
               Exit Function

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Scott
mailto:[email protected][email protected]</A>

[Scott Turchin]

I subclassed mine, perhaps that has something to do with it?

Dialog New 0, g_szMine,g_Top, g_Left,300,30, %WS_MINIMIZEBOX Or %WS_CAPTION Or %WS_SYSMENU Or %WS_EX_LEFT  To hDlg
Control Add ComboBox, hDlg, %IDCOMBOBOX, HistArray(), 5, 1, 290,120, %CBS_DROPDOWN Or %WS_TABSTOP
Dialog Send hDlg, %WM_SETICON, %ICON_BIG, hIcon
Menu Attach hMenu, hDlg
Dialog Show Modal hDlg Call DialogProc To g_Result

Array Scan HistArray(1), = "", To lCount
If OldCBProc Then SetWindowLong hCombo, %GWL_WNDPROC, OLDCBProc
 

'In the Main Window callback:

    Case %WM_INITDIALOG 
        Control Handle hDlg, %IDCOMBOBOX To hCombo   'Sub-class, to trap keyboard events
        OldCBProc = SetWindowLong(hCombo, %GWL_WNDPROC, CodePtr(CBProc))
        ComboBox Select hDlg, %IDCOMBOBOX, 1   


'¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤
' Combobox subclass
'¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤
Function CBProc(ByVal hWnd As Long, ByVal wMsg As Long, _
                ByVal wParam As Long, ByVal lParam As Long) As Long
Local KeyNum As Long

Select Case wMsg
    Case %WM_KEYDOWN
    Case %WM_CHAR
    Case %WM_KEYUP
    Case %CB_GETDROPPEDSTATE 'get enter key from a %CBS_DROPDOWN combo
         Control Get Text hDlg ,%IDCOMBOBOX To g_szDestURL
         Incr lCount
         HistArray(lCount) = g_szDestURL 'Add to array to write to disk.
'         ComboBox Add hDlg, %IDCOMBOBOX, g_szDestURL
         g_Result = ShellExecute(ByVal %NULL, "open", g_szDestURL + Chr$(0), ByVal %NULL, ByVal %NULL,%SW_SHOWMAXIMIZED)
End Select
Function = CallWindowProc(OldCBProc, hWnd, wMsg, wParam, lParam)
End Function

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Scott
mailto:tn[email protected][email protected]</A>

[Bern Ertl]

Scott,

I'm no expert by any means, by from my limited testing, it appears that the COMBOBOX GET TEXT function only retrieves text if the user makes a selection from the list box. If the user types something in the text box, it does not recognize it.

I noticed that you used the CONTROL GET TEXT in your subclassing procedure. That's the function which Semen pointed out will correctly retrieve the edit box text.

Bernard Ertl



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[Scott Turchin]

Good point, whomever gave me the code (Semen?) may have already learned thhat.
The subclass is definitely for when a user enters text and hit enters.




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Scott
mailto:[email protected][email protected]</A>