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TControl.Create Constructor

Creates an instance of TControl.

Pascal
constructor Create(AOwner: TComponent); override;
C++
virtual __fastcall TControl(TComponent * AOwner);

Calling Create constructs and initializes an instance of TControl. However, you should never attempt to instantiate a TControl. This class is intended solely as a base class from which other control classes descend and you should only call Create to instantiate one of these descendants. 

Create calls the parent constructor and initializes the control.  

When overriding Create, always call the inherited Create method first, then proceed with the control's initialization. Remember to specify the override directive when overriding the Create method.

Note: If a control's constructor allocates resources or memory, also override the destructor to free those resources.
 

Delphi Examples: 

 

{
This examples requires a TPageControl and a TCheckBox.  The
form OnCreate event handler populates each sheet with an
edit control placed somewhere on the client area of the
sheet.  Unchecking the checkbox will cause the client area
(not the tab area) of the Tab Control to become invisible.
}
procedure TForm1.CheckBox1Click(Sender: TObject);
begin
  PageControl1.ActivePage.Visible := CheckBox1.Checked;
end;

procedure TForm1.PageControl1Change(Sender: TObject);
begin
  CheckBox1.Checked := PageControl1.ActivePage.Visible;
end;

procedure TForm1.FormCreate(Sender: TObject);
var
  i: Integer;
begin
  for i := 0 to 9 do
    with TTabSheet.Create(Self) do
    begin
      PageControl := PageControl1;
      Caption := 'TabSheet' + IntToStr(i);
      with TEdit.Create(Self) do
      begin
        Parent := PageControl1.Pages[i];
        Left := Random(PageControl1.ActivePage.ClientWidth - Width);
        Top := Random(PageControl1.ActivePage.ClientHeight - Height);
      end;
    end;
    PageControl1Change(Sender);
end;

 

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