RAD Studio VCL Reference
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Occurs when the form is created.
property OnCreate: TNotifyEvent;
__property TNotifyEvent OnCreate;
Use OnCreate to perform special processing when the form is created and is invoked by TCustomForm's constructor. Either implement this event or override the constructor of the form; do not do both. Any objects created in the OnCreate event should be freed by the OnDestroy event.
When a form is being created and its Visible property is true, the following events occur in the order listed:
C++ Examples:
/* This example requires a new TPageControl, as is, with no new pages created at design time, and a TUpDown control, also from the Win95 page of the component palette. The form OnCreate event handler adds several new TabSheet controls to the Page Control. The UpDown1Click event handler fires when the user clicks the up or down button on the TUpDown control. The SelectNextPage method of the Page Control goes forward the comparison (Button = btNext) evaluates as true. If Button is not btNext, the previous Tab Page is selected. */ void __fastcall TForm1::FormCreate(TObject *Sender) { const TColor colorPalette[12] = { clRed, clGreen, clYellow, clBlue, clWhite, clFuchsia, clTeal, clNavy, clMaroon, clLime, clOlive, clPurple}; for (int i = 0; i < 10; i++) { TTabSheet *page = new TTabSheet(PageControl1); // These tabsheets are cleaned up by their owner (PageControl1). page->PageControl = PageControl1; page->Caption = AnsiString("Page") + IntToStr(i); page->Brush->Color = colorPalette[i]; } } void __fastcall TForm1::UpDown1Click(TObject *Sender, TUDBtnType Button) { PageControl1->SelectNextPage(Button == btNext); }
Delphi Examples:
{ This example requires a new TPageControl, as-is, with no new pages created at design time, and a TUpDown control, also from the Win95 page of the component palette. The form OnCreate event handler adds several new TabSheet controls to the Page Control. The UpDown1Click event handler fires when the user clicks the up or down button on the TUpDown control. The SelectNextPage method of the Page Control goes forward the comparison (Button = btNext) evaluates as true. If Button is not btNext, the previous Tab Page is selected. } procedure TForm1.FormCreate(Sender: TObject); var i: Integer; const colorPalette: Array[0..11] of TColor = (clRed, clGreen, clYellow, clBlue, clWhite, clFuchsia, clTeal, clNavy, clMaroon, clLime, clOlive, clPurple); begin for i := 0 to 9 do with TTabSheet.Create(Self) do begin PageControl := PageControl1; Caption := 'TabSheet #' + IntToStr(i); Brush.Color := colorPalette[i]; end; end; procedure TForm1.UpDown1Click(Sender: TObject; Button: TUDBtnType); begin PageControl1.SelectNextPage(Button = btNext); end;
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