TclComboBox

Combobox is a box that opens in the form of a list. It is used in events such as data listing, data selection. Its appearance is close to AddNewEdit, but there is an arrow button on the right side that will enable it to open downwards. In this way, when you press the unlock button, you have the chance to choose among the data listed in it.

AddNewComboBox(TComponent,xName) : TClComboBox

TComponent : The variable name of the defined component is written. Here you should write the component variable name of whatever your component will be in.

xName : The name of the defined combobox should be written.

Feature	Use of	Definition
TClComboBox	testCombo : TClComboBox;	A variable belonging to the TClComboBox class is created.
AddNewComboBox	testCombo := MyForm.AddNewComboBox(MyForm,'testCombo');	A new ComboBox is added to the form.
AddItem	testCombo.AddItem('key1','value1');	In order to add data to the list in the Combobox, we need to use "AddItem". You must write the key value in the first parameter in the "AddItem" definition. This is the area you want to appear on the screen. You should write the value it will hold in the second parameter.
tbeOnChange	MyForm.AddNewEvent(testCombo,tbeOnChange,'ComboSelected');	tbeOnChange is used as the event for clicking on the combobox.
ItemIndex	testCombo.ItemIndex	Specifies the index of the selected item. That is, it determines which element is selected.
GetValueIndex	testCombo.GetValueIndex(testCombo.ItemIndex);	Returns the value of the selected string. In other words, it returns the value1 of the field defined by saying testCombo.AddItem('key1','value1').
GetItemIndex	testCombo.GetItemIndex(testCombo.ItemIndex)	Returns the key of the selected string. In other words, it returns the key1 value of the field defined by saying testCombo.AddItem('key1','value1').
Items	testCombo.Items[testCombo.ItemIndex];	This does the same thing as the GetItemIndex definition above.
Width	testCombo.Width := 150;	Allows the width of columns to be adjusted.
Height	testCombo.Height := 50;	llows the height of columns to be adjusted.
Align	testCombo.Align := alTop;	With the Align parameter, you can specify where you want our component to be aligned in the form. This parameter has multiple positioning properties. See the page to learn about these features.
Margins	testCombo.Margins.Left:= 50; // Right, Top, Bottom	With the Margins parameter, you can give margins at any scale from the right, left, bottom, top.
Clear	testCombo.Clear;	The Clear method is used to clear the elements of a TclComboBox component.

Example:
Now let's make an example where we can show the value of the selected one in the message box when we select and select one of the days.

Basic Syntax

var
  MyForm:TclForm;
  testCombo : TClComboBox;
  testLabel :TClLabel;

  procedure ComboSelected;
  var
    strValue,strKey,strKey2 : String;
  begin
    strValue := testCombo.GetValueIndex(testCombo.ItemIndex);
    strKey := testCombo.GetItemIndex(testCombo.ItemIndex);
    strKey2 := testCombo.Items[testCombo.ItemIndex];

    ShowMessage('strValue : '+strValue); //value1
    ShowMessage('strKey : '+strKey); //key
    ShowMessage('strKey2 : '+strKey2); //key
    ShowMessage('testCombo.ItemIndex : '+IntToStr(testCombo.ItemIndex)); //index 
  end;
  
begin
  MyForm := TclForm.Create(Self);
  
  testLabel:= MyForm.AddNewLabel(MyForm,'testLabel','Select the day');
  testLabel.Align:=alMostTop;
  testLabel.StyledSettings := ssFamily;
  testLabel.TextSettings.FontColor := clAlphaColor.clHexToColor('#820000');
  testLabel.TextSettings.Font.Size:=20;
  testLabel.Width := 150;
  testLabel.Height := 25;
  testLabel.Margins.Top:=50;
  testLabel.Margins.Left :=50;
  testLabel.Margins.Right :=50;
  
  testCombo := MyForm.AddNewComboBox(MyForm,'testCombo');
  testCombo.Align := alTop;
  testCombo.Width := 150;
  testCombo.Margins.Top:=10;
  testCombo.Margins.Left :=50;
  testCombo.Margins.Right :=50;
  
  testCombo.AddItem('Monday','01');
  testCombo.AddItem('Tuesday','02');
  testCombo.AddItem('Wednesday','03');
  testCombo.AddItem('Thursday','04');
  testCombo.AddItem('Friday','05');
  testCombo.AddItem('Saturday','06');
  testCombo.AddItem('Sunday','07');
  
  MyForm.AddNewEvent(testCombo,tbeOnChange,'ComboSelected');
  MyForm.Run;
end;

TRObject Syntax

var
 MyForm:TclForm;
 testCombo : TClComboBox;
 testLabel :TClLabel;

 void ComboSelected;
 var
   strValue,strKey,strKey2 : String;
 {
   strValue = testCombo.GetValueIndex(testCombo.ItemIndex);
   strKey = testCombo.GetItemIndex(testCombo.ItemIndex);
   strKey2 = testCombo.Items[testCombo.ItemIndex];

   ShowMessage('strValue : '+strValue); //value1
   ShowMessage('strKey : '+strKey); //key
   ShowMessage('strKey2 : '+strKey2); //key
   ShowMessage('testCombo.ItemIndex : '+IntToStr(testCombo.ItemIndex)); //index 
 }

{
 MyForm = TclForm.Create(Self);

 testLabel= MyForm.AddNewLabel(MyForm,'testLabel','Select the day');
 testLabel.Align=alMostTop;
 testLabel.StyledSettings = ssFamily;
 testLabel.TextSettings.FontColor = clAlphaColor.clHexToColor('#820000');
 testLabel.TextSettings.Font.Size=20;
 testLabel.Width = 150;
 testLabel.Height = 25;
 testLabel.Margins.Top=50;
 testLabel.Margins.Left =50;
 testLabel.Margins.Right =50;

 testCombo = MyForm.AddNewComboBox(MyForm,'testCombo');
 testCombo.Align = alTop;
 testCombo.Width = 150;
 testCombo.Margins.Top=10;
 testCombo.Margins.Left =50;
 testCombo.Margins.Right =50;

 testCombo.AddItem('Monday','01');
 testCombo.AddItem('Tuesday','02');
 testCombo.AddItem('Wednesday','03');
 testCombo.AddItem('Thursday','04');
 testCombo.AddItem('Friday','05');
 testCombo.AddItem('Saturday','06');
 testCombo.AddItem('Sunday','07');

 MyForm.AddNewEvent(testCombo,tbeOnChange,'ComboSelected');
 MyForm.Run;
}

Output:

See Also

• Object Properties
• AddNewEvent