Announcement

**Mark Hunter** · 30 Oct 2007, 06:57 PM

A simplified version of the example program is given below. The keyboard gets detected only after you click the window. If the first thing you do is press keys they will not be detected.

This morning I asked PB support about this. Here’s their reply to the first – I assume it’s OK to quote support email:

The static control on the graphic window must have the keyboard focus before it can receive a key board message. The easiest solution would be to subclass the dialog of the graphic window and catch a WM_SETFOCUS message and set the focus to the static control, this way the dialog will never receive the keyboard focus, only the static control will.

Code:

%WM_NCHITTEST = &H084
%GW_CHILD = 5
%GWL_WNDPROC = -4
%WM_MOUSEMOVE = &H200
%WM_LBUTTONDOWN = &H201
%WM_RBUTTONDOWN = &H204
%WM_KEYDOWN = &H100

Type POINTAPI
  x As Long
  y As Long
End Type

Declare Function GetWindow Lib "USER32.DLL" Alias "GetWindow" (ByVal hWnd As Dword, ByVal wCmd As Dword) As Long
Declare Function SetWindowLong Lib "USER32.DLL" Alias "SetWindowLongA" (ByVal hWnd As Dword, ByVal nIndex As Long, ByVal lNewLong As Long) As Long
Declare Function CallWindowProc Lib "USER32.DLL" Alias "CallWindowProcA" (ByVal lpPrevWndFunc As Dword, ByVal hWnd As Dword, ByVal uMsg As Dword, ByVal wParam As Dword, ByVal lParam As Long) As Long
'================================================================

Global GraphicWindowChildOldProc As Long
Global finished As Long
'----------------------------------------------------------------

' Called whenever keyboard or mouse activity is detected in the graphics window.
Function GraphicWindowChildNewProc(ByVal hWnd As Dword, ByVal wMsg As Dword, ByVal wParam As Dword, ByVal lParam As Long) As Long
  Local p As POINTAPI

  Select Case wMsg
     Case %WM_NCHITTEST
     Case %WM_MOUSEMOVE
       p.x = Lo(Word, lParam)  ' Current mouse X Position in the graphic window.
       p.y = Hi(Word, lParam)  ' Current mouse Y Position in the graphic window.
       Print "Mouse at " + Format$(Lo(Word, lParam)) + "," + Format$(Hi(Word, lParam))
     Case %WM_LBUTTONDOWN
       Print "Left -click at " + Format$(Lo(Word,lParam)) + "," + Format$(Hi(Word,lParam))
     Case %WM_RBUTTONDOWN
       Print "Right-click at " + Format$(Lo(Word,lParam)) + "," + Format$(Hi(Word,lParam))
     Case %WM_KEYDOWN
       If Chr$(WPARAM) = $Esc Then
         finished = 1
       Else
         Print Chr$(wparam)
       End If
  End Select

  Function = CallWindowProc(GraphicWindowChildOldProc, hWnd, wMsg, wParam, lParam)
End Function
'----------------------------------------------------------------

Function PBMain
  Local hGraphicWindow As Dword
  Local hStatic As Dword
  Local w As Long

  Graphic Window "Graphic Window SubClassing Example", 0, 0, 320, 240 To hGraphicWindow

  ' Retrieve handle to static control (the graphic) on the graphic window (dialog box).
  hStatic = GetWindow(hGraphicWindow, %GW_CHILD)

  ' Subclass the graphic window; any keyboard or mouse activity in the window
  ' will cause the GraphicWindowChildNewProc function to be called.
  GraphicWindowChildOldProc = SetWindowLong(hStatic, %GWL_WNDPROC, CodePtr(GraphicWindowChildNewProc))

  Console Set Loc 320,0

  Graphic Attach hGraphicWindow, 0, ReDraw
  Graphic Font "Times New Roman", 14, 0
  Graphic Print "Move mouse, click, type."
  Graphic Print "Press Esc to quit"
  Graphic ReDraw

  ' Loop until Esc is pressed on the graphic window.
  While finished = 0
    Incr w
    ' Every third iteration give back one time slice
    ' to Windows to prevent 100% CPU utilization.
    If w Mod 3 = 0 Then
      Sleep 0
    End If
  Wend
End Function

**Bob Zale** · 30 Oct 2007, 11:38 PM

Mark--

For a particular window (any window) to receive keyboard input, it must have the focus. That window can receive the focus programatically, or by physically "clicking" on it. That choice is entirely up to you, but it is a prerequisite. This isn't likely to change in the future.

Regards,

Bob Zale
PowerBASIC Inc.

**Michael Mattias** · 31 Oct 2007, 09:56 AM

1. I do not believe the question was about anticipated changes to Windows; rather, it was a question if there are any anticipated changes to the compiler to not require the use of subclassing to capture mouse/keyboard notifications.

Of course this would get into "vaporware" so no answer should be anticipated.

2. Since I don't have CC "dot=oh-four" I can't test Steve's examples, but the SDK doc says pretty clearly...

. Although static controls are child windows, they cannot be selected. Therefore, they cannot receive the keyboard focus and cannot have a keyboard interface..

I'm just wondering what the application requirements are..

2. (Speculation, but good speculation ) ....if you DO need a 'real' keyboard interface on a graphic window, I can't see anything to stop you from adding a child window to that graphic window of any class... 'edit' comes to mind to take in keystrokes and get input from the user. CreateWindowEx works just fine with PB/CC.

I don't see a "window procedure interface" in the GRAPHIC WINDOW but if subclassing works for the static control no reason it shouldn't work for an explicitly-added edit control.

Then again, when you start gettng into controls and such, the PB/Windows compiler might be a better choice of tool. The GRAPHICS commands appear identical, so that part of the program would be pretty much the same.

MCM

**Mark Hunter** · 31 Oct 2007, 11:12 AM

[beginning text deleted]

If you kept the console I suppose you could use some sort of set focus command.

Note that you can’t use Graphic Print within the "callback" function, you need to set a variable to what you want to print, then print it later (say in PBMain), within a loop that checks that variable.

**Mark Hunter** · 7 Nov 2007, 02:12 PM

More on the 4.03/4.04 difference ...

Say you have several graphic windows on the screen at once. And each window has “buttons” on it – really just areas that are checked for mouse-click’s – and each button has a shortcut key.

Naturally you want all these keys to work in all the windows, regardless which has the focus.

In both 4.03 and 4.04 if you process the mouse and keyboard in the a subclassing procedure for a window, the window must have the focus (from clicking) before the keys will work.

However, in 4.03 you could subclass a window twice, once for the mouse and once for the keyboard, in different ways. In what follows win1 and win2 are PB handles for two graphic windows.

GW1 = GetWindow(win1, %GW_CHILD)
GWold1 = SetWindowLong(GW1, %GWL_WNDPROC, CodePtr(GWnew1))
GW2 = GetWindow(win2, %GW_CHILD)
GWold2 = SetWindowLong(GW2, %GWL_WNDPROC, CodePtr(GWnew2))

GWold1k = SetWindowLong(win1, %GWL_WNDPROC, CodePtr(GWnew_k))
GWold2k = SetWindowLong(win2, %GWL_WNDPROC, CodePtr(GWnew_k))

where GWnew1 and GWnew2 process mouse-clicks, GWnew_k processes the keyboard.

This works in 4.03 (when it probably shouldn't) and not in 4.04.

**Mark Hunter** · 8 Nov 2007, 02:20 PM

The following code displays two graphic windows side by side, sans console. When you click on either window you will see printed where, and which mouse button. When you type letters they will be displayed in that window.

It works as it ought to, in 4.04.

It doesn’t work in the earlier version, 4.03, though something like it can be made to work with some extra code.

Code:

#Console Off
'----------------------------------------------------------------

' From WinAPI32 ...
%WM_NCHITTEST = &H084
%HTTRANSPARENT = -1
%HTCLIENT = 1
%GW_CHILD = 5
%GWL_WNDPROC = -4
%WM_LBUTTONDOWN = &H201
%WM_RBUTTONDOWN = &H204
%WM_KEYDOWN = &H100
Declare Function GetWindow Lib "USER32.DLL" Alias "GetWindow" (ByVal hWnd As Dword, ByVal wCmd As Dword) As Long
Declare Function SetWindowLong Lib "USER32.DLL" Alias "SetWindowLongA" (ByVal hWnd As Dword, ByVal nIndex As Long, ByVal lNewLong As Long) As Long
Declare Function CallWindowProc Lib "USER32.DLL" Alias "CallWindowProcA" (ByVal lpPrevWndFunc As Dword, ByVal hWnd As Dword, ByVal uMsg As Dword, ByVal wParam As Dword, ByVal lParam As Long) As Long
'=================================
			===========================

Global GraphicWindowChildOldProc1 As Dword
Global GraphicWindowChildOldProc2 As Dword
Global GWold1k As Dword
Global GWold2k As Dword

Global whichWindow As Long     'in window 1 or 2
Global ky As Long              'keycode
Global whichButton As Long     'button left or right (1 or 2)
Global xmouse, ymouse As Long  'mouse-click position

' Zero/Non-zero  ky  and  whichButton  are also used as flags for
' keyboard and mouse activity, respectively.
'----------------------------------------------------------------

' Called whenever keyboard or mouse activity is detected in the FIRST window.
Function GraphicWindowChildNewProc1(ByVal hWnd As Dword, ByVal wMsg As Dword, ByVal wParam As Dword, ByVal lParam As Long) As Long
  Local result As Dword

  result = CallWindowProc(GraphicWindowChildOldProc1, hWnd, wMsg, wParam, lParam)
  Select Case wMsg
     Case %WM_NCHITTEST
       If result = %HTTRANSPARENT Then result = %HTCLIENT
     Case %WM_LBUTTONDOWN
       xmouse = Lo(Word, lParam) :ymouse = Hi(Word, lParam)
       whichWindow = 1
       whichButton = 1
     Case %WM_RBUTTONDOWN
       xmouse = Lo(Word, lParam) :ymouse = Hi(Word, lParam)
       whichWindow = 1
       whichButton = 2
     Case %WM_KEYDOWN
       ky = wParam
       whichWindow = 1
  End Select

  Function = result
End Function
'----------------------------------------------------------------

' Called whenever keyboard or mouse activity is detected in the SECOND window.
Function GraphicWindowChildNewProc2(ByVal hWnd As Dword, ByVal wMsg As Dword, ByVal wParam As Dword, ByVal lParam As Long) As Long
  Local result As Dword

  result = CallWindowProc(GraphicWindowChildOldProc2, hWnd, wMsg, wParam, lParam)

  Select Case wMsg
     Case %WM_NCHITTEST
       If result = %HTTRANSPARENT Then result = %HTCLIENT
     Case %WM_LBUTTONDOWN
       xmouse = Lo(Word, lParam) :ymouse = Hi(Word, lParam)
       whichWindow = 2
       whichButton = 1
     Case %WM_RBUTTONDOWN
       xmouse = Lo(Word, lParam) :ymouse = Hi(Word, lParam)
       whichWindow = 2
       whichButton = 2
     Case %WM_KEYDOWN
       ky = wParam
       whichWindow = 2
  End Select

  Function = result
End Function
'----------------------------------------------------------------

Function PBMain
  Local hGraphicWindow1 As Dword
  Local hGraphicWindow2 As Dword
  Local hStatic As Dword
  Local w As Long

  ' Create two graphic windows side by side
  Graphic Window "",   0, 0, 398, 400 To hGraphicWindow1
  Graphic Window "", 400, 0, 398, 400 To hGraphicWindow2

  ' Subclass
  hStatic = GetWindow(hGraphicWindow1, %GW_CHILD)
  GraphicWindowChildOldProc1 = SetWindowLong(hStatic, %GWL_WNDPROC, CodePtr(GraphicWindowChildNewProc1))
  hStatic = GetWindow(hGraphicWindow2, %GW_CHILD)
  GraphicWindowChildOldProc2 = SetWindowLong(hStatic, %GWL_WNDPROC, CodePtr(GraphicWindowChildNewProc2))

  ' Print instructions on the windows
  Graphic Attach hGraphicWindow1, 0, ReDraw
  Graphic Font "Times New Roman", 12, 0
  Graphic Print " Click or type,  press Esc to quit."
  Graphic ReDraw
  Graphic Attach hGraphicWindow2, 0, ReDraw
  Graphic Font "Times New Roman", 12, 0
  Graphic Print " Click or type,  press Esc to quit."
  Graphic ReDraw

 ' Start with the second window having the focus
  Graphic Set Focus

  ' Continually check  ky  for keyboard activity and
  ' whichwindow  for mouse activity.  Print on the
  ' window that was last clicked.  (Or
  Do
    Incr w
    If w Mod 3 = 0 Then
      Sleep 0                          ' give time slice to Windows
    End If

    If ky Then
      If whichWindow = 1 Then
       Graphic Attach hGraphicWindow1, 0, ReDraw
      Else
       Graphic Attach hGraphicWindow2, 0, ReDraw
      End If

      If     ky = Asc($Esc) Then
       Exit Do
      ElseIf ky = Asc($Cr) Then
       Graphic Print "[CR]"
      ElseIf ky = Asc($Spc) Then
       Graphic Print "[space]";
      Else
       Graphic Print Chr$(ky);
      End If
      Graphic ReDraw
      ky = 0                            'reset for next time
    End If

    If whichButton Then
      If whichWindow = 1 Then
       Graphic Attach hGraphicWindow1, 0, ReDraw
      Else
       Graphic Attach hGraphicWindow2, 0, ReDraw
      End If

      Graphic Print " - Button"; Str$(whichbutton);
      Graphic Print "  at "; Str$(xmouse); ","; Str$(ymouse)
      Graphic ReDraw
      whichButton = 0                   'reset for next time
    End If
  Loop
End Function

Announcement

Capturing mouse and keyboard messages from a graphic Window in PBCC 4.04

Capturing mouse and keyboard messages from a graphic Window in PBCC 4.04

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