How to Use GridView Filter Row in RadMultiColumnCombobox

Environment

Product Version	Product	Author
2021.2.511	RadMultiColumnCombobox	Desislava Yordanova

Description

This tutorial demonstrates a sample approach how to enable the filtering row in the popup grid and filter the records according to the user's input in the particular column.

Solution

Create an extension Filtering method for the RadMultiColumnComboBox. It enables the filtering row in the popup grid.

• C#
• VB.NET

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

    private void Form1_Load(object sender, EventArgs e)
    { 
        this.customersTableAdapter.Fill(this.nwindDataSet.Customers);

        this.radMultiColumnComboBox1.DataSource = this.customersBindingSource;
        this.radMultiColumnComboBox1.DisplayMember = "ContactName";
        this.radMultiColumnComboBox1.ValueMember = "CustomerID";
        this.radMultiColumnComboBox1.AutoSizeDropDownToBestFit = true;
        this.radMultiColumnComboBox1.AutoSizeDropDownColumnMode = BestFitColumnMode.AllCells;

        this.radMultiColumnComboBox1.Filtering(true);
    }
}

internal static class ExtensionsRadMultiColumnComboBox
{
    public static void Filtering(this RadMultiColumnComboBox combo, bool enable)
    {
        if (enable)
        {
            if (!combo.EditorControl.EnableFiltering)
            {
                combo.DropDownClosing += RadMultiColumnComboBoxDropDownClosing;

                var multiColumnComboBoxElement = combo.MultiColumnComboBoxElement;
                multiColumnComboBoxElement.EditorControl.EnableFiltering = true;
                multiColumnComboBoxElement.EditorControl.ShowFilteringRow = true;
                multiColumnComboBoxElement.EditorControl.FilterChanging +=
                    RadMultiColumnComboBoxEditorControlFilterChanging;
            }
        }
        else
        {
            if (combo.EditorControl.EnableFiltering)
            {
                combo.DropDownClosing -= RadMultiColumnComboBoxDropDownClosing;

                var multiColumnComboBoxElement = combo.MultiColumnComboBoxElement;
                multiColumnComboBoxElement.EditorControl.EnableFiltering = false;
                multiColumnComboBoxElement.EditorControl.ShowFilteringRow = false;
                multiColumnComboBoxElement.EditorControl.FilterChanging -=
                    RadMultiColumnComboBoxEditorControlFilterChanging;
            }
        }
    }

    private static void RadMultiColumnComboBoxEditorControlFilterChanging(object sender,
        GridViewCollectionChangingEventArgs e)
    {
        var multiColumnComboGridView = sender as MultiColumnComboGridView;
        if (multiColumnComboGridView == null)
            return;
        if (multiColumnComboGridView.Parent == null)
            return;
        var radPopupControlBase = multiColumnComboGridView.Parent as MultiColumnComboPopupForm;
        if (radPopupControlBase == null)
            return;
        if (!radPopupControlBase.IsDisplayed)
            return;
        if (e.OldItems == null)
            return;
        if (e.OldItems.Count == 0)
            return;
        var filterDescriptor = e.OldItems[0] as FilterDescriptor;
        if (filterDescriptor == null)
            return;
        var grid = multiColumnComboGridView;
        var currentRow = grid.CurrentRow;
        if (currentRow.RowElementType != typeof (GridFilterRowElement))
            return;
        var value = currentRow.Cells[filterDescriptor.PropertyName].Value ?? string.Empty;
        if (value == null)
            return;
        string activeEditorString = null;
        if (grid.ActiveEditor != null)
        {
            var activeEditorValue = grid.ActiveEditor.Value ?? string.Empty;
            activeEditorString = activeEditorValue.ToString();
        }
        if (e.NewValue == null && value.ToString() != string.Empty &&
            !(activeEditorString != null && activeEditorString == string.Empty &&
              grid.CurrentColumn.Name == filterDescriptor.PropertyName))
            e.Cancel = true;
    }

    private static void RadMultiColumnComboBoxDropDownClosing(object sender, RadPopupClosingEventArgs args)
    {
        var radMultiColumnComboBox = sender as RadMultiColumnComboBox;
        if (radMultiColumnComboBox == null)
            return;
        var popupForm = radMultiColumnComboBox.MultiColumnComboBoxElement.PopupForm;
        var editorControl = radMultiColumnComboBox.MultiColumnComboBoxElement.EditorControl;
        MultiColumnComboBoxDropDownClosingHandler(popupForm, editorControl, args);
    }

    private static void MultiColumnComboBoxDropDownClosingHandler(RadPopupControlBase popupForm,
        RadGridView editorControl, RadPopupClosingEventArgs args)
    {
        var mousePosition = Control.MousePosition;
        var xIn = mousePosition.X >= popupForm.Location.X &&
                  mousePosition.X <= popupForm.Location.X + popupForm.Size.Width;
        var yIn = mousePosition.Y >= popupForm.Location.Y &&
                  mousePosition.Y <= popupForm.Location.Y + popupForm.Size.Height;
        if (editorControl.CurrentRow.Index == -1 && xIn && yIn)
        {
            args.Cancel = true;
        }
        else
        {
            if (editorControl.ActiveEditor != null)
            {
                editorControl.ActiveEditor.EndEdit();
            }
            editorControl.FilterChanging -= RadMultiColumnComboBoxEditorControlFilterChanging;
            foreach (var column in editorControl.Columns)
            {
                column.FilterDescriptor = null;
            }
            editorControl.FilterChanging += RadMultiColumnComboBoxEditorControlFilterChanging;
        }
    }
}

Public Class RadForm1
    Private Sub RadForm1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        Me.CustomersTableAdapter.Fill(Me.NwindDataSet.Customers)

        Me.RadMultiColumnComboBox1.DataSource = Me.CustomersBindingSource
        Me.RadMultiColumnComboBox1.DisplayMember = "ContactName"
        Me.RadMultiColumnComboBox1.ValueMember = "CustomerID"
        Me.RadMultiColumnComboBox1.AutoSizeDropDownToBestFit = True
        Me.RadMultiColumnComboBox1.AutoSizeDropDownColumnMode = BestFitColumnMode.AllCells
        Me.RadMultiColumnComboBox1.Filtering(True)
    End Sub
End Class

Module ExtensionsRadMultiColumnComboBox
    <Extension()>
    Sub Filtering(ByVal combo As RadMultiColumnComboBox, ByVal enable As Boolean)
        If enable Then

            If Not combo.EditorControl.EnableFiltering Then
                AddHandler combo.DropDownClosing, AddressOf RadMultiColumnComboBoxDropDownClosing
                Dim multiColumnComboBoxElement = combo.MultiColumnComboBoxElement
                multiColumnComboBoxElement.EditorControl.EnableFiltering = True
                multiColumnComboBoxElement.EditorControl.ShowFilteringRow = True
                AddHandler multiColumnComboBoxElement.EditorControl.FilterChanging, AddressOf RadMultiColumnComboBoxEditorControlFilterChanging
            End If
        Else

            If combo.EditorControl.EnableFiltering Then
                RemoveHandler combo.DropDownClosing, AddressOf RadMultiColumnComboBoxDropDownClosing
                Dim multiColumnComboBoxElement = combo.MultiColumnComboBoxElement
                multiColumnComboBoxElement.EditorControl.EnableFiltering = False
                multiColumnComboBoxElement.EditorControl.ShowFilteringRow = False
                RemoveHandler multiColumnComboBoxElement.EditorControl.FilterChanging, AddressOf RadMultiColumnComboBoxEditorControlFilterChanging
            End If
        End If
    End Sub

    Private Sub RadMultiColumnComboBoxEditorControlFilterChanging(ByVal sender As Object, ByVal e As GridViewCollectionChangingEventArgs)
        Dim multiColumnComboGridView = TryCast(sender, MultiColumnComboGridView)
        If multiColumnComboGridView Is Nothing Then Return
        If multiColumnComboGridView.Parent Is Nothing Then Return
        Dim radPopupControlBase = TryCast(multiColumnComboGridView.Parent, MultiColumnComboPopupForm)
        If radPopupControlBase Is Nothing Then Return
        If Not radPopupControlBase.IsDisplayed Then Return
        If e.OldItems Is Nothing Then Return
        If e.OldItems.Count = 0 Then Return
        Dim filterDescriptor = TryCast(e.OldItems(0), FilterDescriptor)
        If filterDescriptor Is Nothing Then Return
        Dim grid = multiColumnComboGridView
        Dim currentRow = grid.CurrentRow
        If currentRow.RowElementType <> GetType(GridFilterRowElement) Then Return
        Dim value = If(currentRow.Cells(filterDescriptor.PropertyName).Value, String.Empty)
        If value Is Nothing Then Return
        Dim activeEditorString As String = Nothing

        If grid.ActiveEditor IsNot Nothing Then
            Dim activeEditorValue = If(grid.ActiveEditor.Value, String.Empty)
            activeEditorString = activeEditorValue.ToString()
        End If

        If e.NewValue Is Nothing AndAlso value.ToString() <> String.Empty AndAlso Not (activeEditorString IsNot Nothing AndAlso
            activeEditorString = String.Empty AndAlso grid.CurrentColumn.Name = filterDescriptor.PropertyName) Then e.Cancel = True
    End Sub

    Private Sub RadMultiColumnComboBoxDropDownClosing(ByVal sender As Object, ByVal args As RadPopupClosingEventArgs)
        Dim radMultiColumnComboBox = TryCast(sender, RadMultiColumnComboBox)
        If radMultiColumnComboBox Is Nothing Then Return
        Dim popupForm = radMultiColumnComboBox.MultiColumnComboBoxElement.PopupForm
        Dim editorControl = radMultiColumnComboBox.MultiColumnComboBoxElement.EditorControl
        MultiColumnComboBoxDropDownClosingHandler(popupForm, editorControl, args)
    End Sub

    Private Sub MultiColumnComboBoxDropDownClosingHandler(ByVal popupForm As RadPopupControlBase, ByVal editorControl As RadGridView, ByVal args As RadPopupClosingEventArgs)
        Dim mousePosition = Control.MousePosition
        Dim xIn = mousePosition.X >= popupForm.Location.X AndAlso mousePosition.X <= popupForm.Location.X + popupForm.Size.Width
        Dim yIn = mousePosition.Y >= popupForm.Location.Y AndAlso mousePosition.Y <= popupForm.Location.Y + popupForm.Size.Height

        If editorControl.CurrentRow.Index = -1 AndAlso xIn AndAlso yIn Then
            args.Cancel = True
        Else

            If editorControl.ActiveEditor IsNot Nothing Then
                editorControl.ActiveEditor.EndEdit()
            End If

            RemoveHandler editorControl.FilterChanging, AddressOf RadMultiColumnComboBoxEditorControlFilterChanging

            For Each column In editorControl.Columns
                column.FilterDescriptor = Nothing
            Next

            AddHandler editorControl.FilterChanging, AddressOf RadMultiColumnComboBoxEditorControlFilterChanging
        End If
    End Sub
End Module