Arrow keys

[Guest]

I have this in a subclass procedure:

case %WM_KEYDOWN
            control get loc ghForm,gControl to x,y
            control get size ghForm,gControl to w,h
            select case wparam
                case %VK_PGUP
                    decr y
                    control set loc ghForm,gControl,x,y
                case %VK_PGDN
                    incr y
                    control set loc ghForm,gControl,x,y
                case %VK_HOME
                    decr x
                    control set loc ghForm,gControl,x,y
                case %VK_END
                    incr x
                    control set loc ghForm,gControl,x,y
                case %VK_F8
                    decr w
                    control set size ghForm,gControl,w,h
                case %VK_F9
                    incr w
                    control set size ghForm,gControl,w,h
                case %VK_F11
                    incr h
                    control set size ghForm,gControl,w,h
                case %VK_F12
                    decr h
                    control set size ghForm,gControl,w,h

This does exactly what I want it to do; however, the keys are rather "non-standard". I would rather use the shift+arrow keys and ctrl+arrow keys. So the subclassing and using %WM_KEYDOWN messages I have got the "hang of", it is just the keys I want to use don't work because I suspect they;like the F10 key, are reserved by default for other use. If I create say two buttons on a form, the arrow keys automatically switch back and forth between the buttons. I looked in the win32api.hlp file for a way to "remap"(for lack of a better term)these keys but didn't find anything. If ya' could give me some insight on the shift,ctrl and arrow keys and a way to define them for specific tasks I would appreciate it.

Thanks,
Adam

[Semen Matusovski]

Adam --
didn't test, but it seems to me, that GeyKeyboardState in this moment should return correct status of all keys (before pressing new key)

------------------

[Guest]

I have done some more playing around and discovered I can intercept the %WM_SYSKEYDOWN message and process the alt+arrow keys no problem but still can't process the aroow keys with %WM_KEYDOWN in the subclass procedure. Hmmmm, interesting - I will continue to experiment. I will also experiment with GetKeyboardstate but it seems to me that is not my answer. The arrow keys seem to be virtual keys just like HOME,END, DELETE and the function keys and I can processs them with no problem. I wonder if there is another message for the arrow keys where I dont' have to use the alt key.
Hmmmmm,....

Regards,
Adam

------------------

[Edmund Melerski]

Adam,
This works for me:
{code}
SELECT CASE wMsg&
CASE %WM_KEYDOWN
KK&=GETKEYSTATE(%VK_SHIFT)
IF KK&=-127 OR KK&=-128 THEN
IF wParam&=%VK_TAB THEN 'Tab to the left
...
...
...
END IF
END IF

SELECT CASE wParam&
CASE %VK_UP 'Up-arrow key
...
...
...
CASE %VK_DOWN 'Down-arrow key
...
...
...
CASE %VK_TAB 'Tab to the right
...
...
...
END SELECT
CASE %WM_KEYUP
...
...
...
CASE %WM_CHAR
...
...
...

END SELECT
[/code]

Edmund

------------------

[Joe Speroni]

Fellows, you seem to be having more sucess at doing what I want
to do. Right now I'm using a MODELESS dialog with

GetMessage(tMsg,%NULL,0,0)

to get keyboard input. I went that way because the keyboard
messages did not appear to be avaialble using a MODAL dialog
with CallBack functions.

Apparently there is a way to get keyboard message inside a
CB function -- subclassing?

Could someone provide a simple DDT skeleton just to be able
to get keyboard messages (right now I'm interested in only
A/N and the ENTER key. I'll process them and then REMOVE them
from Windows purview. All others would be passed thru to
Windows. No need for fancy Fn or cursor controls (yet).

I'd appreciate any suggestions.

Aloha,



------------------

[Semen Matusovski]

Adam --
Try this (at least on my PC - Win2000 - works) - see code bellow


[This message has been edited by Semen Matusovski (edited February 29, 2000).]

[Guest]

Hey y'all,
Thanks for the replies. Since my last post I played around with the code and discovered that if I do this:

case %WM_KEYUP
            keystate = GetAsyncKeyState(%VK_CONTROL)
            control get loc ghForm,gControl to x,y
            control get size ghForm,gControl to w,h
            select case wparam
                case %VK_UP
                    if keystate then
                        decr h  
                        control set size ghForm,gControl,w,h
                    else
                        decr y
                        control set loc ghForm,gControl,x,y
                    end if
                case %VK_DOWN
                    if keystate then
                        incr h
                        control set size ghForm,gControl,w,h
                    else
                        incr y
                        control set loc ghForm,gControl,x,y
                    end if
                case %VK_LEFT
                    if keystate then
                        decr w
                        control set size ghForm,gControl,w,h
                    else
                        decr x
                        control set loc ghForm,gControl,x,y
                    end if
                case %VK_RIGHT
                    if keystate then
                        incr w
                        control set size ghForm,gControl,w,h
                    else
                        incr x
                        control set loc ghForm,gControl,x,y
                    end if

As you can see Edmund, I basically came up with the same thing that you use. This code does what I want except for one minor detail - since the repeat count for the %WM_KEYUP is always one(for obvious reasons),I have to keep plunking on the arrow keys to move or resize the controls I create. I can move the controls with just the arrow keys and use CTRL+arrow keys to resize the controls. The continous plunking is not a major issue although it would be nice to do repeating(Life will continue though if I can't). I would be curious as to why when I simply switch the message from %WM_KEUP to %WM_KEYDOWN, the arrow keys stop being processed. Hmmmmmmm, I guess I will have to do some more experimenting on this. I will check out you code Semen and see if that will allow me to use %WM_KEYDOWN and the arrow keys. Joe, try Semen's code that he posted in this thread and see if that works, also there is an example of subclassing that was posted by Lance sometime ago, let me go back and get the url for it and I will post it again for ya'.

Thanks guys,
Adam

------------------

[Guest]

here's the url joe,
. hope this helps as well as semens' example.

regards,
adam


------------------

[Guest]

Hmmmmm, the arrow keys are still acting like tab keys even when I use %WM_KEYUP,if I create more than one control on a form,pressing the arrow keys tabs between the controls. I thought that was what the TAB key was for. Interesting...

Regards,
Adam


------------------

[Danny Faris]

Semen: Your code works great! I've been trying to find such code for a good couple weeks now, and it is a real reliefe to see PowerBasic trap the keystrokes in a dialog. Thank you SO much for the help!

I have one question. I want to capture control+letter keystrokes in my dialog, but I don't have a clue how to go about it. I know the message is sent to my While loop in the form of a %WM_Char message, but there is no %VK_A definition to use in conjunction with your control checking IF statement. I tried selecting a case for %WM_CHAR and using a CASE 97 statement followed by the If statement to check for control, but it refuses to recognise that anything was pressed. Any suggestions?

------------------

[Guest]

Oh hey all,
I got my arrow key processing working in response to a %WM_KEYDOWN message. It turned out it was due to a modal\modeleless issue in one of the other windows that is showing simultaneouly with the window I am doing the arrow key processing. Problem corrected, works just great now.

Regards,
Adam

------------------

[Semen Matusovski]

Danny --
try this

#Compile Exe
#Register None
DefLng A-Z
#Include "Win32Api.Inc"
Global Stop&

CallBack Function hDlg_CB
   Select Case CbMsg
      Case %WM_DESTROY: Stop = 1
   End Select
End Function

Function PbMain()
   Local Msg  As tagMsg
   Dialog New 0 ,"SubClass ?", 0, 0, 200, 100, %DS_CENTER Or %WS_SYSMENU To hDlg
   Control Add Label,  hDlg, 101, "Label", 10, 5, 30, 12
   Control Add TextBox,  hDlg, 201, "Edit control-1", 10, 25, 170, 12
   Control Add Button,  hDlg, 102, "&Button", 40, 5, 130, 12
   Control Add TextBox,  hDlg, 202, "Edit control-2", 10, 45, 170, 12
   Control Add ComboBox, hDlg, 301,, 10, 65, 170, 100, %CBS_DROPDOWNLIST Or %WS_TABSTOP
   ComboBox Add hDlg, 301, "Combo box": ComboBox Select hDlg, 301, 1
   Dialog Show Modeless hDlg Call hDlg_CB
   While GetMessage(Msg, %NULL, 0, 0)
      Local Title$: Title$ = ""
      Select Case Msg.message
         Case %WM_SYSKEYDOWN
            Select Case Msg.wParam
               Case %VK_LEFT : Title$ = "ALT + LEFT ARROW"
               Case %VK_RIGHT: Title$ = "ALT + RIGHT ARROW"
               Case %VK_DOWN : Title$ = "ALT + ARROW DOWN"
               Case %VK_UP   : Title$ = "ALT + ARROW UP"
            End Select
         Case %WM_KEYDOWN
            If IsTrue(LoWrd(GetKeyState(%VK_CONTROL)) And &H8000) Then
               Select Case Msg.wParam
                  Case %VK_LEFT : Title$ = "CONTROL + LEFT ARROW"
                  Case %VK_RIGHT: Title$ = "CONTROL + RIGHT ARROW"
                  Case %VK_DOWN : Title$ = "CONTROL + ARROW DOWN"
                  Case %VK_UP   : Title$ = "CONTROL + ARROW UP"
                  Case 65 To 90 : Title$ = "CONTROL + " + Chr$(Msg.wParam)
               End Select
            ElseIf IsTrue(LoWrd(GetKeyState(%VK_SHIFT)) And &H8000) Then
               Select Case Msg.wParam
                  Case %VK_LEFT : Title$ = "SHIFT + LEFT ARROW"
                  Case %VK_RIGHT: Title$ = "SHIFT + RIGHT ARROW"
                  Case %VK_DOWN : Title$ = "SHIFT + ARROW DOWN"
                  Case %VK_UP   : Title$ = "SHIFT + ARROW UP"
               End Select
            End If
      End Select
      If Title$ <> "" Then
         If Msg.hWnd = GetDlgItem(hDlg, 201) Then Title$ = Title$ + " in TextBox-1" Else _
         If Msg.hWnd = GetDlgItem(hDlg, 202) Then Title$ = Title$ + " in TextBox-2" Else _
         If Msg.hWnd = GetDlgItem(hDlg, 301) Then Title$ = Title$ + " in Combo Box"
         SetWindowText hDlg, ByVal StrPtr(Title$)
      ElseIf IsDialogMessage(hDlg, Msg) = %FALSE Then  ' Don't touch Tab
         TranslateMessage Msg
         DispatchMessage Msg
      End If
      If Stop <> 0 Then Exit Do
   Loop
   MsgBox "Ok"
End Function

%VK_A to %VK_Z are not included, because they are equal ASC' codes
%VK_A = ASC("A") = 65
...
%VK_Z = ASC("Z") = 90

[This message has been edited by Semen Matusovski (edited February 29, 2000).]

[Danny Faris]

Semen: You have a very impressive understanding of how the messages in a dialog are processed. I'm impressed! Thanks so much for your quick reply; the code works great and now ctrl+d pops up a date box anywhere in my application-even in the dialog!

Again, thanks for all the help.--Danny.

------------------

[Lance Edmonds]

Just to be clear: Semen's code is using an (as yet) undocumented method of processing the message queue for the DDT engine - R&D have not told me if this is a 100% safe technique. Use this technique "at you own risk".



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

[Danny Faris]

Thanks Lance, I'll keep that in mind. Sorry to be such a bother everyone, I'm trying to make F10 a local toggle in one of my dialogs, and capture the print screen key to make it actually do something useful. Thus, I've used the Case %VK_F10 and Case %VK_Print statements Under the Select Case Msg.Message, Case %WM_KeyDown, Select Case Msg.wParam statements in my message loop to capture these keys, but the case never happens. What am I doing wrong this time?

Thanks so much for your help.

Danny.

------------------

[Semen Matusovski]

Danny --
I guess that Print Screen not works, because Windows reserves this key for copying image of Desktop to clipboard and doesn't transfer this message to apps.
Better to forget about this key.

About F10. - On my PC - no problems, similar like with others F1..F12 (%WM_KEYDOWN).

On your PC could be resident programs (screen savers, keyboard drivers ...), which reserve this key (try to remember additional programs).

To say true, I know one, enoough simple way to found Print Screen pressing (SetWindowHookEx), but I don't like this technique.
Also this code doesn't prevent copying of desktop's image to clipboard.
For example:

   #Compile Exe
   #Register None
   #Dim All
   #Include "win32Api.inc"
   Global ghKbrdHook As Long
   Global lpfnKbrdHook As Long
   Global hDlg As Long
   
   Function KeyboardHook(ByVal iCode As Integer, ByVal wParam As Long, ByVal lParam As Long) As Long
      If iCode = %HC_ACTION And wParam = &H2C Then
         SetWindowText hDlg, "Print Screen pressed " + Time$
         ' Function = 1: Exit Function
      End If
      Function = CallNextHookEx(ghKbrdHook, iCode, wParam, lParam)
   End Function
   
   CallBack Function Cb
      Select Case CbMsg
         Case %WM_INITDIALOG
            ghKbrdHook = SetWindowsHookEx(%WH_KEYBOARD, CodePtr(KeyboardHook), _
               0, GetCurrentThreadId)
         Case %WM_DESTROY
            UnhookWindowsHookEx ghKbrdHook
      End Select
   End Function
   
   Function PbMain
      Dialog New 0,"Test",,,200,100, %ws_sysmenu To hdlg
      Control Add TextBox, hdlg,100, "", 10, 10,180, 12, %WS_BORDER
      Dialog Show Modal hdlg Call Cb
   End Function

[This message has been edited by Semen Matusovski (edited April 03, 2000).]