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Thomymaster

Combobox question (only do something if the element has changed)

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Thomymaster

Hi

I have a GUI setup (in OnEvent mode) with a combobox with 3 elements. I want to invoke some function only if the user clicked on a different control in the combobox then before.

I use the  $CBN_SELCHANGE constant in my WM_COMMAND function to check for the selection but i noticed something strange:

- when i click on the arrow top open the combobox, the $CBN_SELCHANGE is triggered

- when i select a value from the combobox, the $CBN_SELCHANGE is triggered 2 times

 

 

Here is my code:

 

GUIRegisterMsg($WM_COMMAND, "MY_WM_COMMAND")

Global Const $idcLastDataType = GUICtrlCreateCombo("",110,161,80,21,67,-1)
GUICtrlSetData(-1,"Value1|Value2")

Func MY_WM_COMMAND($hWnd, $iMsg, $iwParam, $ilParam)
    Local $idControl = _LoWord($iwParam)        ; LoWord - this gives the ControlID of the control which sent the message
    Local $nNotifyCode = _HiWord($iwParam)      ; HiWord - this gives the submessage that was sent
    Local $sWinTitle=WinGetTitle($hWnd)
    ;Local $hCtrl = $ilParam
    If $GUI_DEBUG Then
        ConsoleWrite("Window handle: " & $hWnd & " | Window title: " & $sWinTitle & " | Control ID: " & $idControl & @CRLF)
    EndIf

    Switch $idControl
        Case $idcLastDataType
                If $CBN_SELCHANGE Then _GUI_LastDataUpdate()
    EndSwitch
    ; Proceed the default Autoit3 internal message commands.
    ; You also can complete let the line out.
    ; !!! But only 'Return' (without any value) will not proceed
    ; the default Autoit3-message in the future !!!
    Return $GUI_RUNDEFMSG
EndFunc

Func _GUI_LastDataUpdate()
    MsgBox(0,"Test","Test)
    Return 1
EndFunc

 

Like i said i want the function to only be invoked if the item is a different one then the last time it was selected.

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Melba23

Thomymaster,

The only way I can see to do this would be to store the selection and compare when a new one is made:

#include <GUIConstantsEx.au3>
#include <MsgBoxConstants.au3>

Opt("GUIOnEventMode", 1)

$sSel = ""

$hGUI = GUICreate("Test", 500, 500)
GUISetOnEvent($GUI_EVENT_CLOSE, "_Exit")

$cCombo = GUICtrlCreateCombo("", 10, 10, 200, 20)
GUICtrlSetData($cCombo, "One|Two|Three|Four|Five")
GUICtrlSetOnEvent($cCombo, "_Combo_Event")

GUISetState()

While 1
    Sleep(10)
WEnd



Func _Combo_Event()
    $sNewSel = GUICtrlRead($cCombo)
    If $sNewSel <> $sSel Then
        $sSel = $sNewSel

        MsgBox($MB_SYSTEMMODAL, "Selection", $sSel)
    EndIf

EndFunc



Func _Exit()
    Exit
EndFunc

And why are you using Windows messaging to check for a selection? You can do it easily with standard OnEvent coding as I have shown.

M23


Any of my own code posted anywhere on the forum is available for use by others without any restriction of any kind._______My UDFs:

Spoiler

ArrayMultiColSort ---- Sort arrays on multiple columns
ChooseFileFolder ---- Single and multiple selections from specified path treeview listing
Date_Time_Convert -- Easily convert date/time formats, including the language used
ExtMsgBox --------- A highly customisable replacement for MsgBox
GUIExtender -------- Extend and retract multiple sections within a GUI
GUIFrame ---------- Subdivide GUIs into many adjustable frames
GUIListViewEx ------- Insert, delete, move, drag, sort, edit and colour ListView items
GUITreeViewEx ------ Check/clear parent and child checkboxes in a TreeView
Marquee ----------- Scrolling tickertape GUIs
NoFocusLines ------- Remove the dotted focus lines from buttons, sliders, radios and checkboxes
Notify ------------- Small notifications on the edge of the display
Scrollbars ----------Automatically sized scrollbars with a single command
StringSize ---------- Automatically size controls to fit text
Toast -------------- Small GUIs which pop out of the notification area

 

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Thomymaster

Hi

 

Thanks for that. I already know that i can use OnEvent coding, but is there a reason not to select for events like button clicks or combox changes using the MY_WM_COMMAND function?

 

Is there an explanation why the combobox throws the $CB_SELCHANGE one time for opening and then 2 times after selecting a value?

Edited by Thomymaster

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Melba23

Thomymaster,

is there a reason not to select for events like button clicks or combox changes using the MY_WM_COMMAND function?

I would suggest that the answer is given by your question in the last line:

 Is there an explanation why the combobox throws the $CB_SELCHANGE one time for opening and then 2 times after selecting a value?

Why use message handlers and make life difficult for yourself when you can use native functions and make it easy? if you use a high level language then using its functions must be a better way.

As to the answer to that question, I have no idea - try looking on MSDN and see if there is an explanation.

M23

Edited by Melba23
Typo

Any of my own code posted anywhere on the forum is available for use by others without any restriction of any kind._______My UDFs:

Spoiler

ArrayMultiColSort ---- Sort arrays on multiple columns
ChooseFileFolder ---- Single and multiple selections from specified path treeview listing
Date_Time_Convert -- Easily convert date/time formats, including the language used
ExtMsgBox --------- A highly customisable replacement for MsgBox
GUIExtender -------- Extend and retract multiple sections within a GUI
GUIFrame ---------- Subdivide GUIs into many adjustable frames
GUIListViewEx ------- Insert, delete, move, drag, sort, edit and colour ListView items
GUITreeViewEx ------ Check/clear parent and child checkboxes in a TreeView
Marquee ----------- Scrolling tickertape GUIs
NoFocusLines ------- Remove the dotted focus lines from buttons, sliders, radios and checkboxes
Notify ------------- Small notifications on the edge of the display
Scrollbars ----------Automatically sized scrollbars with a single command
StringSize ---------- Automatically size controls to fit text
Toast -------------- Small GUIs which pop out of the notification area

 

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Thomymaster

OK, i got your point :)

  • Like 1

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XinYoung


Hello.

I implemented this but now it's stuck in the _Combo_Event function. How can I get past this so I can make the UI do other things, like close if Cancel is pressed?

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XinYoung

OK I realized this "Opt("GUIOnEventMode", 1)" is causing the UI to not recognize that other buttons are being pressed.

When I comment it out, my different Cases in While 1 are working, but then the _Combo_Event doesn't get triggered.

Any ideas???

Edited by XinYoung

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