Hi,

I'm looking for ideas on how to get the information typed on the keyboard
into an edit control. I'm putting together a combination of edit control and
listbox for a custom locator combobox. I've got everything working except
for when the listbox has the focus and the users type in character for
search on. I tried stuffing the keyboard characters into the edit control's
text property, but when the user presses the backspace key the edit control
doesn't backspace - it gets a $08 inserted in to the text.

Is there a better way to send keyboard input from the listbox to the edit
control using Windows messages instead? Would this make the edit control
react to non-text keys like backspace correctly? Can someone point out what
message to use and how to use it?

-Andy
andyw...@ix.netcom.com

Andy,

provide message handlers for WM_KEYDOWN, WM_CHAR and WM_KEYUP for your listbox
and send the messages on to the edit control via SendMessage or Perform.

Peter Below (TeamB)  100113.1...@compuserve.com)

-Andy
andyw...@ix.netcom.com

if you want to have your listbox/edit combination perform as a unit from the
component users view both should be encapsulated into a single component and
that would indeed best be done with a derivative of TListbox that has handlers
for the messages i mentioned. For a quick&dirty solution one could tie a
normal TEdit and TListbox together with event handlers on the form level, but
it would be ugly stuff, something like this (untested!):

  Function IsListboxKey(Key: Word): Boolean;
  Begin
    case Key Of
      VK_UP, VK_DOWN, VK_HOME, VK_END, VK_PRIOR, VK_NEXT:
        Result := True
    Else
      Result := False
    End;
  End;  

  //listbox OnKeyDown, OnKeyUp and OnKeyPress handlers:
  Procedure TForm1.Listbox1KeyDown( Sender: TObject;
     Var Key: Word; Shift: TShiftState );
  Begin
    If not ((Alt In Shift) or IsListboxKey(Key)) Then Begin
      PostMessage( edit1.handle, WM_KEYDOWN, Key,
                   MakeLong( 0, MapVirtualkey( Key, 0)));
      Key := 0;
    End;  
  End;                  

  Procedure TForm1.Listbox1KeyUp( Sender: TObject;
     Var Key: Word; Shift: TShiftState );
  Begin
    If not ((Alt In Shift) or IsListboxKey(Key)) Then Begin
      PostMessage( edit1.handle, WM_KEYDOWN, Key,
                   MakeLong( 1, MapVirtualkey( Key, 0) or $C000));
      Key := 0;
    End;  
  End;                  

  Procedure TForm1.Listbox1KeyPress( Sender: TObject;
     Var Key: Char; Shift: TShiftState );
  Begin
    If not (Alt In Shift) Then
      Key := #0;
  End;

Peter Below (TeamB)  100113.1...@compuserve.com)