how to create an append-only edit?

[automotizator]

i want to create an edit (hEdit=GUICtrlCreateEdit() ) to which the user can only append text.

i made it read-only and tried to fetch an event by $msg = GUIGetMsg() and then using a Select and case $msg=$hEdit.

but that doesn't seem to work.

ultimately i want to create an edit which serves as a terminal, the user can't delete the text that already exists in the edit, he can append text and delete his own text (as long it wasn't sent).

thank you

[PhoenixXL]

Example

#include <GuiEdit.au3>
#include <GuiConstantsEx.au3>

Opt('MustDeclareVars', 1)

$Debug_Ed = False ; Check ClassName being passed to Edit functions, set to True and use a handle to another control to see it work

_Main()

Func _Main()
Local $hEdit

; Create GUI
GUICreate("Edit Append Text", 400, 300)
$hEdit = GUICtrlCreateEdit("This is a test" & @CRLF & "Another Line", 2, 2, 394, 268)
GUISetState()

_GUICtrlEdit_AppendText($hEdit, @CRLF & "Append to the end?")

; Loop until user exits
Do
Until GUIGetMsg() = $GUI_EVENT_CLOSE
GUIDelete()
EndFunc ;==>_Main

You can even disable the control but setting the Edit to read-only has more better results

Regards

[automotizator]

but i want that the user will be able to append the text, and if he press backspace i'll ignore it.

[PhoenixXL]

This should help

expandcollapse popup

#include <EditConstants.au3>
#include <GUIConstantsEx.au3>
#include <GUIEdit.au3>
#include <WindowsConstants.au3>

Global $s_Edit_Data = ''

Example()

Func Example()
; Create a GUI with various controls.
Local $hGUI = GUICreate('Example')

GUICtrlCreateEdit('', 10, 20)

; Display the GUI.
GUISetState(@SW_SHOW, $hGUI)

; Register the WM_COMMAND to intercept when the value in the first input's value is changed.
GUIRegisterMsg($WM_COMMAND, 'WM_COMMAND')

While 1
Switch GUIGetMsg()
Case $GUI_EVENT_CLOSE
ExitLoop
EndSwitch
WEnd

; Delete the previous GUI and all controls.
GUIDelete($hGUI)
EndFunc   ;==>Example


Func WM_COMMAND($hWnd, $iMsg, $wParam, $lParam)
#forceref $hWnd, $iMsg, $lParam
Local $iHiWord = _WinAPI_HiWord($wParam) ; Control identification code.
Switch $iHiWord
Case $EN_CHANGE ; When a change event is intercepted.
Local $iLoWord = _WinAPI_LoWord($wParam) ; Control identifier.
Local $iEdit_Len = StringLen(GUICtrlRead($iLoWord))

;Lets check if deletion of characters was intercepted
If $iEdit_Len >= StringLen($s_Edit_Data) Then
$s_Edit_Data = GUICtrlRead($iLoWord)
Else ;Get the data which has been replaced and substitute it in the insertion point
GUICtrlSetData($iLoWord, StringMid( $s_Edit_Data, _GetCaretOffset($iLoWord) + 1, 1 ), 1)
EndIf

EndSwitch
Return $GUI_RUNDEFMSG
EndFunc   ;==>WM_COMMAND

;Taken from the PredictText Library
Func _GetCaretOffset($Edit_ID)
Local $Edit_Handle = GUICtrlGetHandle($Edit_ID)
Local $_LineIndex = _GUICtrlEdit_GetSel($Edit_Handle)
If Not IsArray($_LineIndex) Then Return SetError(1, 0, -1)
Switch $_LineIndex[0]
Case $_LineIndex[1]
Return SetExtended(0, $_LineIndex[1])
Case Else
Local $_CoordMode = Opt('CaretCoordMode', 2)
Local $_Caret = WinGetCaretPos()
Local $_TextPos = _GUICtrlEdit_PosFromChar($Edit_Handle, $_LineIndex[0])
Opt('CaretCoordMode', $_CoordMode)
Return SetExtended(1, $_TextPos[0] = $_Caret[0] And $_Caret[1] = $_TextPos[1])
EndSwitch
EndFunc   ;==>_GetCaretOffset

Edited March 1, 2013 by PhoenixXL

[PhoenixXL]

This is a more better implementation

expandcollapse popup

#include <EditConstants.au3>
#include <GUIConstantsEx.au3>
#include <WinAPI.au3>
#include <WindowsConstants.au3>
#include <Constants.au3>

Global $wProcNew, $wProcOld, $VK_BACK = 0x8

Example()

Func Example()
; Create a GUI with various controls.
Local $hGUI = GUICreate('Example')

GUICtrlCreateEdit('', 10, 20)
Local $hEdit = GUICtrlGetHandle(-1)
_Edit_Block_BackSpace($hEdit)

; Display the GUI.
GUISetState(@SW_SHOW, $hGUI)

While GUIGetMsg() <> $GUI_EVENT_CLOSE
Sleep(10)
WEnd

;callback-deregister
DllCallbackFree($wProcNew)
;Unsubclass
_WinAPI_SetWindowLong($hEdit, $GWL_WNDPROC, DllCallbackGetPtr($wProcOld))
; Delete the previous GUI and all controls.
GUIDelete($hGUI)
EndFunc   ;==>Example


Func _Edit_Block_BackSpace($hEdit)
;Ge the handle of the dll callback
$wProcNew = DllCallbackRegister("_MyWindowProc", "ptr", "hwnd;uint;long;ptr")
;subclass the edit control
$wProcOld = _WinAPI_SetWindowLong($hEdit, $GWL_WNDPROC, DllCallbackGetPtr($wProcNew))
;return the old procedure
Return $wProcOld
EndFunc   ;==>_Edit_Block_BackSpace

Func _MyWindowProc($hWnd, $uiMsg, $wParam, $lParam)
Switch $uiMsg
Case $WM_CHAR
Switch $wParam
Case $VK_BACK
Return 0
EndSwitch
EndSwitch

;pass the unhandled messages to default WindowProc
Return _WinAPI_CallWindowProc($wProcOld, $hWnd, $uiMsg, $wParam, $lParam)
EndFunc   ;==>_MyWindowProc

Ask if you have any questions

Edit : added the cleanup part as suggested by M23

Regards

Edited March 2, 2013 by PhoenixXL

[Melba23]

PhoenixXL,

Nothing wrong with the concept at all - no need to have reported it.

But in my opinion you should really delete the subclassed control and free the new WndProc with DllCallbackFree in the code before exiting the script - rather than leaving it up to AutoIt to do the cleanup work for you as at present.

M23