New subject: Fwd: [Pharo-project] Issue 1064 in pharo: There are still problem with keyboard shortcuts in Windows

6 Mar 2011


      Hi, I fordward this thread to the VM mailing list since it looks more
appropiated.
David, here "tn" is proposing a fix. I am not qualified to take a look.
Hope it helps
Mariano
---------- Forwarded message ----------
From: pharo@googlecode.com
Date: Sat, Mar 5, 2011 at 9:23 PM
Subject: Re: [Pharo-project] Issue 1064 in pharo: There are still problem
with keyboard shortcuts in Windows
To: pharo-project@lists.gforge.inria.fr
Comment #14 on issue 1064 by happy.lo...@gmail.com: There are still problem
with keyboard shortcuts in Windows
http://code.google.com/p/pharo/issues/detail?id=1064
Hi, I'm tn.
'ctrl + m' problem is Cog VM bug.
Normally, when character key is pushed, keyboard events occur as follows on
Squeak.
1. key press (down)
2. character (character code notification)
3. key release (up)
They are produced by a primitive method in IutEventFetcher >>
primGetNextEvent.
But when ctrl + m is pushed, a character event doesn't occur.
Because 'ctrl + m' value is 13. The value is same as ENTER key.
Cog VM ignores WM_CHAR message(character event) when ENTER key is pushed.
The one of solution for this problem is to add CTRL key state to the
if-condition.
-- sqWin32Window.c --
int recordKeyboardEvent(MSG *msg) {
 ...
switch(msg->message) {
   ...
case WM_CHAR:
   case WM_SYSCHAR:
     /* Note: VK_RETURN is recorded as virtual key ONLY */
     if(keyCode == 13  && !ctrl) return 1;            // add "&& !ctrl"
     pressCode = EventKeyChar;
     break;
   ...
 }
 ...
Note: ENTER keyCode is 13. But when ctrl + ENTER is pushed, the keyCode is
10.
So if the condition is revised, ctrl + m problem is corrected.
but other behavior is not changed.
If you want to prevent to generate character event for CTRL + ENTER,
you can add following code. By this way, we can produce
not only ctrl+m (0x0D)'s character event but also ctrl+j (0x0A)'s one.
-- sqWin32Window.c --
// add this function
static int isNotKeyDownCtrlReturn(MSG* msgp){
   if(msgp->message == WM_KEYDOWN && msgp->wParam == VK_RETURN){
       if(GetKeyState(VK_CONTROL) & 0x8000) {
           return FALSE;
       }
   }
   return TRUE;
}
...
int ioProcessEvents(void)
{ static MSG msg;
 ...
     if(isNotKeyDownCtrlReturn(&msg)){  // add
       TranslateMessage(&msg);
     }                                  // add
     DispatchMessage(&msg);
 ...
}
...
int recordKeyboardEvent(MSG *msg) {
 ...
if(pressCode == EventKeyDown && virtCode != 0 &&
isNotKeyDownCtrlReturn(lastMessage) ) {
                                                  // add " &&
isNotKeyDownCtrlReturn(lastMessage) "
   /* generate extra character event */
   ...
 }
 return 1;
}
An attached file is source, which has been corrected by above way.
Note: Below is a comment in the source code.
/* note: several keys are not reported as character events;
    most noticably the mapped virtual keys. For those we
    generate extra character events here */
Those keys(e.g. arrow) should not be ascii code.
ENTER key is not. but an extra character events is created for ENTER.
I don't think this behavior is correct.
As for ENTER key, an extra character event must not be generated,
and WM_CHAR message should be processed.
Please see MSDN about TranslateMessage.
see also Comment 11.
Thanks,
Attachments:
       sqWin32Window.c  99 KB