OpenEuphoria

Re: Trapping the TAB key

• Posted by euman at bellsouth.net May 06, 2002
• 389 views

----- Original Message ----- 
From: "Jonas Temple" <jktemple at yhti.net>
> 
> Does anyone know how, using Win32lib, to trap when the TAB key is 
> pressed in: edit control, combo, dropdownlist?

I dont mind helping those who help theirself.....

Here's what you need to look for Jonas.....

global function shift_left (atom x, integer count)
  return x * power (2, count)  
end function

global function MAKELONG (atom a, atom b)
 return or_bits (a, shift_left (b, 16))
end function

atom user32
user32 = open_dll("user32.dll")

constant 
xPeekMessage = define_c_func(user32,
 "PeekMessageA",{C_POINTER,C_LONG,C_UINT,C_UINT,C_UINT},C_LONG)
,xGetParent = define_c_func(user32, "GetParent",{C_LONG},C_LONG)
,xSendMessage = define_c_func(user32, "SendMessageA", {C_LONG, C_LONG, C_INT,
C_LONG}, C_LONG)

global function SendMessage(atom hwnd, atom msg, atom wParam, atom lParam)
   return c_func(xSendMessage,{hwnd, msg, wParam, lParam}) 
end function

constant WM_CHAR = 258,
              PM_REMOVE = 1

-- this should be consealed in your edit controls subclass  in "if iMsg =
WM_KEYDOWN then"
if wParam = 9 then -- handle tabkey fo edit control
junk = c_func(xPeekMessage,{tagMSG, c_func(xGetParent,{handle}), 0, 0,
  PM_REMOVE})
  junk = SendMessage(handle, WM_CHAR, wParam, MAKELONG(1, 14)) 
end if            

handle will be the control ID....should work the same for MLE's, Combo's etc,
etc..

This traps the tabkey by sending a message to itself for further processing.

WOW, Cool eh?

Euman