TEdit.OnChange event handler is calling twice for same text

Original Reporter info from Mantis: accorp @accorp

• Reporter name:

Description:

If edit text is modified inside OnChange handler:

procedure TForm1.Edit1Change(Sender: TObject);
begin
  Edit1.Text:='from-on-change';
end;

then executing

  Edit1.Text:='test';

trigger OnChange event one time for 'test' and twice for 'from-on-change'.

Additional information:

Method TWinControl.RealSetText is calling TControl.RealSetText with old value, while text was already updated.

procedure TWinControl.RealSetText(const AValue: TCaption); // AValue = 'test'
begin
  ...
  WSSetText(AValue); // call OnChange, set text to 'from-on-change'
  ...
  inherited RealSetText(AValue); // text was modified, but AValue = 'test'
  ...
end;

procedure TControl.RealSetText(const Value: TCaption);
begin
  if RealGetText = Value then Exit; // 'from-on-change' &LtPos;> 'test' 
  FCaption := Value;
  Perform(CM_TEXTCHANGED, 0, 0); // extra OnChange
end;

Mantis conversion info:

• Mantis ID: 32602
• OS: Xubuntu 16.04
• Build: r56166
• Version: 1.9 (SVN)
• Monitored by: » a.ramos (a.ramos), » @onpok (Ondrej Pokorny), » @flyingsheep (Bart Broersma)