TreeList.ShowFilterPopupListBox Event
Fires before a pop-up filter menu is displayed. Allows you to customize the value list.
Namespace: DevExpress.XtraTreeList
Assembly: DevExpress.XtraTreeList.v24.2.dll
NuGet Packages: DevExpress.Win.Navigation, DevExpress.Win.TreeList
#Declaration
[DXCategory("Behavior")]
public event FilterPopupListBoxEventHandler ShowFilterPopupListBox
#Event Data
The ShowFilterPopupListBox event's data class is DevExpress.XtraTreeList.FilterPopupListBoxEventArgs.
#Remarks
If the TreeListColumn.OptionsFilter.FilterPopupMode property is set to List, the pop-up filter menu contains a value list. You can handle the ShowFilterPopupCheckedListBox event to customize the list (for instance, disable or hide particular values).
#Example
The following example shows how to remove default “(Blanks)” and “(Non blanks) items from the Name Column’s Filter DropDown.
using System;
using System.Windows.Forms;
using DevExpress.XtraTreeList;
namespace ShowFilterPopupListBox_example
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void treeList1_ShowFilterPopupListBox(object sender, FilterPopupListBoxEventArgs e)
{
if (e.Column.FieldName == "Name")
{
//Removes "(Blanks)"
e.ComboBox.Items.RemoveAt(0);
//Removes "(Non blanks)"
e.ComboBox.Items.RemoveAt(0);
}
}
private void Form1_Load(object sender, EventArgs e)
{
this.table1TableAdapter.Fill(this.treelistdbDataSet.Table1);
}
}
}