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TreeList.ShowFilterPopupCheckedListBox Event

Fires before a pop-up filter menu is displayed. Allows you to customize the value checklist.

Namespace: DevExpress.XtraTreeList

Assembly: DevExpress.XtraTreeList.v24.2.dll

NuGet Packages: DevExpress.Win.Navigation, DevExpress.Win.TreeList

#Declaration

[DXCategory("Behavior")]
public event FilterPopupCheckedListBoxEventHandler ShowFilterPopupCheckedListBox

#Event Data

The ShowFilterPopupCheckedListBox event's data class is DevExpress.XtraTreeList.FilterPopupCheckedListBoxEventArgs.

#Remarks

If the TreeListColumn.OptionsFilter.FilterPopupMode property is set to CheckedList, the pop-up filter menu contains a value checklist. You can handle the ShowFilterPopupCheckedListBox event to customize the checklist (for instance, disable or hide particular values).

#Example

The following example shows how to remove the “(Select All)” item from the Department Column’s Filter DropDown.

ShowFilterPopupCheckedListBox

using System;
using System.Windows.Forms;
using DevExpress.XtraTreeList;

namespace ShowFilterPopupCheckedListBox_example
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            this.table1TableAdapter.Fill(this.treelistdbDataSet.Table1);
        }

        private void treeList1_ShowFilterPopupCheckedListBox(object sender, FilterPopupCheckedListBoxEventArgs e)
        {
            if (e.Column.FieldName != "Department") return;
            // disable "(Select All)" item
            e.CheckedComboBox.SelectAllItemVisible = false;
        }
    }
}
See Also