TRadioGroup/ja

│ Deutsch (de) │ English (en) │ suomi (fi) │ français (fr) │ 日本語 (ja) │ русский (ru) │

TRadioGroupは、関連するが相互に排他的なTRadioButtonのグループであり、ユーザーに対して選択肢の1つを選択する必要がある。それは、統合されたTRadioButtonsを持つ TGroupBoxのようなものである。

使い方

FormでTRadioGroupを使用するには、単純にComponentパレットのStandardタブでそれを選択し、フォームをクリックして配置します。

Small example

Geometric figures should be drawn randomly and depending on the TRadioGroups to the form. The first RadioGroup determines the shape, the second RadioGroup detrmines the number.

• create a new application and place two TRadioGroups on your form
• change in the Object Inspector the property Name of RadioGroup1 to rgShape, also RadioGroup2 to rgCount
• change identical Caption of rgShape to Shape and that of rgCount to Count
• add the RadioButtons for rgShape:
  • in the Object Inspector select the property Items of rgShape
  • click on the button [...], the character chain editor opens
  • write among each other Lines Rectangles Ellipses and complete the entry with the button OK
• add identical the RadioButtons for rgCount (written among each other): 1 5 10 20 50 100
• set the first RadioButton as the currently selected, by setting the property ItemIndex of rgShape and rgCount from -1 to 0
• create the OnClick event handler of rgShape by double clicking rgShape
• also use these event handler for rgCount:
  • in the Object Inspector select rgCount
  • now select the tab Events in the Object Inspector
  • go to the OnClick event and select in the adjacent ComboBox rgShapeClick
• whenever rgShape or rgCount is clicked, the form should be redrawn, therefore write following code in the event handler:

procedure TForm1.rgShapeClick(Sender: TObject);
begin
  Repaint;
end;

• whenever the form is redrawn, the shapes should be drawn:
  • in the Object Inspector select Form1
  • select the tab Events
  • click on the button [...] next to the event OnPaint
  • the handler is created, enter the following code:

procedure TForm1.FormPaint(Sender: TObject);
var
  i: Integer;
begin
  if TryStrToInt(rgCount.Items[rgCount.ItemIndex], i) then
    for i:=1 to i do begin
      Canvas.Pen.Color:=Random($1000000);
      Canvas.Brush.Color:=Random($1000000);
      case rgShape.Items[rgShape.ItemIndex] of
        'Lines':      Canvas.Line(Random(ClientWidth), Random(ClientHeight), Random(ClientWidth), Random(ClientHeight));
        'Rectangles': Canvas.Rectangle(Random(ClientWidth), Random(ClientHeight), Random(ClientWidth), Random(ClientHeight));
        'Ellipses':   Canvas.Ellipse(Random(ClientWidth), Random(ClientHeight), Random(ClientWidth), Random(ClientHeight));
      end;
    end;
end;

• start your program, it could look like:

See also

• TRadioGroup doc
• TRadioButton
• TGroupBox