TCheckGroup

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A TCheckGroup tcheckgroup.png is a control that comprises a group of TCheckBox items physically and logically grouped together on a container component.

Usage

To use a TCheckGroup on a form, you can simply select it on the Standard tab of the Component Palette and place it by clicking on the form.

Small example

It changes the background color of a form. This color is determined by adding the individual color components:

  • create a new application and place a TCheckGroup on your form
  • in the object inspector change the property Name of CheckGroup1 to cgRed and the caption to Red
  • add the checkboxes for cgRed:
    • in the object inspector select the property Items of cgRed
    • click on the button [...], the character chain editor opens
    • write among one another 1 2 4 8 16 32 64 128 and complete the entry with the OK button
  • copy this TCheckGroup by right click cgRed in the form and click on Copy
  • right-click the form and click on Insert, which creates TCheckGroup named cgRed1
  • now change the Name of cgRed1 to cgGreen and the Caption to Green
  • insert even a TCheckGroup and change the name to cgBlue and the caption to Blue
  • whenever a CheckBox is clicked, the color will change:
    • in the object inspector create the OnItemClick event handler of cgRed by clicking the button [...] next to the event OnItemClick
    • select for cgGreen and cgBlue also this event handler, by choosing each next to the event OnItemClick ComboBox cgRedItemClick
    • write following code in the event handler:
procedure TForm1.cgRedItemClick(Sender: TObject; Index: integer);
var
  i, c: Integer;
begin
  c := $000000;                                          // first the color is black
  for i:=0 to 7 do begin                                 // test Items 0..7 of all Checkgroups
    if cgRed.Checked[i]   then c := c + 1 shl i;         // amount of red   $000000..$0000FF
    if cgGreen.Checked[i] then c := c + 1 shl (i + 8);   // amount of green $000000..$00FF00
    if cgBlue.Checked[i]  then c := c + 1 shl (i + 16);  // amount of blue  $000000..$FF0000
  end;
  Color := c;
end;
  • start your program, it could look like:

ExampleTCheckGroup.png


Accessing the Check Boxes

Each item in the TCheckGroup has a Checked property, to set them all to checked do

for i := 0 to MyCheckGroup.items.Count-1 do   // check all the categories we found.
    MyCheckGroup.Checked[i] := true;

You can add items at run time by using TCheckGroup.Items, its a TStrings list. To add an new checkbox to the set, just do MyCheckGroup.Items.add('CheckThis'); Similarly, to remove all items, clear the list, MyCheckGroup.Items.clear;

See also


LCL Components
Component Tab Components
Standard TMainMenu • TPopupMenu • TButton • TLabel • TEdit • TMemo • TToggleBox • TCheckBox • TRadioButton • TListBox • TComboBox • TScrollBar • TGroupBox • TRadioGroup • TCheckGroup • TPanel • TFrame • TActionList
Additional TBitBtn • TSpeedButton • TStaticText • TImage • TShape • TBevel • TPaintBox • TNotebook • TLabeledEdit • TSplitter • TTrayIcon • TControlBar • TFlowPanel • TMaskEdit • TCheckListBox • TScrollBox • TApplicationProperties • TStringGrid • TDrawGrid • TPairSplitter • TColorBox • TColorListBox • TValueListEditor
Common Controls TTrackBar • TProgressBar • TTreeView • TListView • TStatusBar • TToolBar • TCoolBar • TUpDown • TPageControl • TTabControl • THeaderControl • TImageList • TPopupNotifier • TDateTimePicker
Dialogs TOpenDialog • TSaveDialog • TSelectDirectoryDialog • TColorDialog • TFontDialog • TFindDialog • TReplaceDialog • TTaskDialog • TOpenPictureDialog • TSavePictureDialog • TCalendarDialog • TCalculatorDialog • TPrinterSetupDialog • TPrintDialog • TPageSetupDialog
Data Controls TDBNavigator • TDBText • TDBEdit • TDBMemo • TDBImage • TDBListBox • TDBLookupListBox • TDBComboBox • TDBLookupComboBox • TDBCheckBox • TDBRadioGroup • TDBCalendar • TDBGroupBox • TDBGrid • TDBDateTimePicker
Data Access TDataSource • TCSVDataSet • TSdfDataSet • TBufDataset • TFixedFormatDataSet • TDbf • TMemDataset
System TTimer • TIdleTimer • TLazComponentQueue • THTMLHelpDatabase • THTMLBrowserHelpViewer • TAsyncProcess • TProcessUTF8 • TProcess • TSimpleIPCClient • TSimpleIPCServer • TXMLConfig • TEventLog • TServiceManager • TCHMHelpDatabase • TLHelpConnector
Misc TColorButton • TSpinEdit • TFloatSpinEdit • TArrow • TCalendar • TEditButton • TFileNameEdit • TDirectoryEdit • TDateEdit • TTimeEdit • TCalcEdit • TFileListBox • TFilterComboBox • TComboBoxEx • TCheckComboBox • TButtonPanel • TShellTreeView • TShellListView • TXMLPropStorage • TINIPropStorage • TJSONPropStorage • TIDEDialogLayoutStorage • TMRUManager • TStrHolder
LazControls TCheckBoxThemed • TDividerBevel • TExtendedNotebook • TListFilterEdit • TListViewFilterEdit • TLvlGraphControl • TShortPathEdit • TSpinEditEx • TFloatSpinEditEx • TTreeFilterEdit • TExtendedTabControl •
RTTI TTIEdit • TTIComboBox • TTIButton • TTICheckBox • TTILabel • TTIGroupBox • TTIRadioGroup • TTICheckGroup • TTICheckListBox • TTIListBox • TTIMemo • TTICalendar • TTIImage • TTIFloatSpinEdit • TTISpinEdit • TTITrackBar • TTIProgressBar • TTIMaskEdit • TTIColorButton • TMultiPropertyLink • TTIPropertyGrid • TTIGrid
SQLdb TSQLQuery • TSQLTransaction • TSQLScript • TSQLConnector • TMSSQLConnection • TSybaseConnection • TPQConnection • TPQTEventMonitor • TOracleConnection • TODBCConnection • TMySQL40Connection • TMySQL41Connection • TMySQL50Connection • TMySQL51Connection • TMySQL55Connection • TMySQL56Connection • TMySQL57Connection • TSQLite3Connection • TIBConnection • TFBAdmin • TFBEventMonitor • TSQLDBLibraryLoader
Pascal Script TPSScript • TPSScriptDebugger • TPSDllPlugin • TPSImport_Classes • TPSImport_DateUtils • TPSImport_ComObj • TPSImport_DB • TPSImport_Forms • TPSImport_Controls • TPSImport_StdCtrls • TPSCustomPlugin
SynEdit TSynEdit • TSynCompletion • TSynAutoComplete • TSynMacroRecorder • TSynExporterHTML • TSynPluginSyncroEdit • TSynPasSyn • TSynFreePascalSyn • TSynCppSyn • TSynJavaSyn • TSynPerlSyn • TSynHTMLSyn • TSynXMLSyn • TSynLFMSyn • TSynDiffSyn • TSynUNIXShellScriptSyn • TSynCssSyn • TSynPHPSyn • TSynTeXSyn • TSynSQLSyn • TSynPythonSyn • TSynVBSyn • TSynAnySyn • TSynMultiSyn • TSynBatSyn • TSynIniSyn • TSynPoSyn
Chart TChart • TListChartSource • TRandomChartSource • TUserDefinedChartSource • TCalculatedChartSource • TDbChartSource • TChartToolset • TChartAxisTransformations • TChartStyles • TChartLegendPanel • TChartNavScrollBar • TChartNavPanel • TIntervalChartSource • TDateTimeIntervalChartSource • TChartListBox • TChartExtentLink • TChartImageList
IPro TIpFileDataProvider • TIpHtmlDataProvider • TIpHttpDataProvider • TIpHtmlPanel
Virtual Controls TVirtualDrawTree • TVirtualStringTree • TVTHeaderPopupMenu