TDateEdit and SelectNext(ActiveControl, False,True)
lazarus / 31-LCL

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talorigomat · 2016-05-20 10:41

I use the following code in a  TEdit and TLabelledEdit OnExit event

         Form1.SelectNext(ActiveControl, False,True)

This has  the effect of the focus not moving to the next control but
remaining on the current control when the tab key is pressed.

The same code placed in a TDateEdit OnExit event doesn't have the same
effect.  The focus moves to the next component when the tab key is
pressed

Is this a bug in Lazarus, or should I use another way to accomplish
the same thing for TDateEdits?

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Bart · 2016-05-20 12:26

TDateEdit is an embedded control, it's parent is a TCustomControl.
Look at the code that handles the Tab Key in the base class of
TDateEdit how it is handled there, that may give you some clu how to
solve this particular problem maybe.

Alternatively can't you just intercept the Tab Key?

Bart

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shacsoft · 2016-07-01 23:33

TDateEdit has their own "PerformTab"

I found these solution:

procedure TForm1.DateEdit1KeyDown(Sender: TObject; var Key: Word;
  Shift: TShiftState);
begin
  if ((key=Vk_Up))  then begin
    Key:=0;
    DateEdit1.PerformTab(false);
  end;
end;

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u2o · 2017-09-17 03:23

Hi all!

Apologies for writing here, but it can help anyone looking for a
solution in the same place.

I don't know if it is a bug, but to set focus forward,
TWinControl.PerformTab(True); doesn't work. I've found one
alternative...

Need assign ControlsAll_OnEnter and ControlsAll_OnKeyDown to the
controls events


Quotevar
    tLastFocused: TObject;  // <-- Save last TObject focused in the
form // Private Variable


procedure TForm1.ControlsAll_OnEnter(Sender: TObject);
begin

  if Sender.ClassType = TEdit then begin
    tLastFocused := Sender;                                       //
Register Last focused Object
  end else if Sender.ClassType = TDateEdit then begin
    tLastFocused := Sender;
  end else if Sender.ClassType = TComboBox then begin
    tLastFocused := Sender;
  end else if Sender.ClassType = TMemo then begin
    tLastFocused := Sender;
  end else if Sender.ClassType = TBitBtn then begin
    tLastFocused := Sender;
  end else begin
    // Disabled, only register some ClassType's
  end;

end;


procedure TForm1.ControlsAll_OnKeyDown(Sender: TObject; var Key: word;
Shift: TShiftState);
var
  cDateEdit: TDateEdit;
  ctWinControl : tWinControl;
begin

  if (Shift = [ssAlt])  and ((key = VK_LEFT)) then begin             
       // Setfocus to backward control

    if tLastFocused.ClassType = TDateEdit then begin
      cDateEdit := TDateEdit(tLastFocused);
      cDateEdit.PerformTab(False);
    end else begin
      SelectNext(TWinControl(tLastFocused), False, True);
    end;

  end else if (Shift = [ssAlt]) and ((key = VK_RIGHT)) then begin    
  // Setfocus to forward control

    if tLastFocused.ClassType = TDateEdit then begin
      cDateEdit := TDateEdit(tLastFocused);
      //cDateEdit.PerformTab(True);                                  
                // <-- ¿Bug? // Don't work
      ctWinControl := FindNextControl(cDateEdit, true, true, true);
      //ShowMessage(ctWinControl .Name.ToUpper);
      ctWinControl.SetFocus;
    end else begin
      SelectNext(TWinControl(tLastFocused), True, True);
    end;

end;