Advanced RadMultiColumnComboBox - filtering with grid filters enabled

2 posts, 0 answers
  1. Boris
    Boris avatar
    2 posts
    Member since:
    May 2012

    Posted 22 Oct 2013 Link to this post


    I have a solution (see example below) how to use RadMultiColumnComboBox auto filter and it's EditorControl's column filters enabled at the same time. Howewer, there is a problem and I'd be glad if you have any solution.

    I've attached a picture of working and non working example of filtering.

    Filtering as shown on page is not enaugh for what I am trying to do.
    My goal is to have RadMultiColumnComboBox auto filtering and also it's EditorControl columns filtering enabled at the same time.
    This example shows how to solve this. But it only works when manipulating with short strings in the RadMultiColumnCombobox's DataSource (which is DataTable). 
    But as soon as longer string is placed inside DataTable, strange problem accures. 
    Try two things:
    1.) Run the program. Click on the RadMultiColumnComboBox. Popup with RadGridView accures automatically. Now click on the LastName filter. Enter character 0. Filtering works for now.
    2.) Now erase this character and enter another one - z. There is no last name that contains letter z, true... but that should not crach the application. The application crashes. Why? If you shorten the first name in the first row and run the application again, this doesn't happen.

    Below there is a Form1.vb with all the code needed. In designer I only have one RadMulticolumnComboBox1 control, placed on Form1.

    Imports Telerik.WinControls.UI
    Imports Telerik.WinControls.Data
    Public Class Form1
        Private shouldNotCancelPopup = True
        Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
            Dim dt As New DataTable
            dt.Rows.Add("Selectt one", "")
            dt.Rows.Add("Very very loooong looong first name", "Last Name 0") 'This one is the troublemaker. I do not know why.
            dt.Rows.Add("Short first name 1", "Last Name 1")
            dt.Rows.Add("Short first name 2", "Last Name 2")
            Me.RadMultiColumnComboBox1.DataSource = dt
            Me.RadMultiColumnComboBox1.EditorControl.Rows(0).IsPinned = True
            Me.RadMultiColumnComboBox1.DisplayMember = "FirstName"
            Me.RadMultiColumnComboBox1.ValueMember = "LastName"
        End Sub
        Public Sub enableEditorControlFiltering(ByRef cb As RadMultiColumnComboBox)
            cb.EditorControl.ShowRowHeaderColumn = False
            cb.EditorControl.EnableFiltering = True
            cb.EditorControl.ShowFilteringRow = True
            AddHandler cb.EditorControl.MouseLeave, AddressOf cb_EditorControl_MouseLeave
            AddHandler cb.DropDownClosing, AddressOf cb_DropDownClosing
            AddHandler cb.EditorControl.CellClick, AddressOf cb_GridWithoutCheckBoxes_CellClick
        End Sub
        Private Sub cb_DropDownClosing(ByVal sender As System.Object, ByVal args As Telerik.WinControls.UI.RadPopupClosingEventArgs)
            If shouldNotCancelPopup Then
                args.Cancel = True       
            End If
        End Sub
        Private Sub cb_EditorControl_MouseLeave(ByVal sender As Object, ByVal e As System.EventArgs) 'Handles cb_EditorControl_MouseLeave.MouseLeave
            shouldNotCancelPopup = False
        End Sub
        Private Sub cb_GridWithoutCheckBoxes_CellClick(ByVal sender As Object, ByVal e As Telerik.WinControls.UI.GridViewCellEventArgs)
                If e.RowIndex >= 0 Then            'If valid row
                    shouldNotCancelPopup = False
                    shouldNotCancelPopup = True
                End If
            Catch ex As Exception
            End Try
        End Sub
        Public Sub setChangeableVisibilityStyle(ByRef cb As RadMultiColumnComboBox)
            cb.MultiColumnComboBoxElement.AutoSizeDropDownToBestFit = True
        End Sub
        Public Sub linkComboBoxFilterWithHisEditorControlFilter(ByVal cb As RadMultiColumnComboBox)
            cb.AutoFilter = True
            Dim filter As New FilterDescriptor()
            filter.PropertyName = cb.DisplayMember
            filter.Operator = FilterOperator.Contains
        End Sub
    End Class

  2. George
    George avatar
    500 posts

    Posted 25 Oct 2013 Link to this post

    Hello Boris,

    Thank you for contacting us.

    I was able to identify where the issue origins from. It appears that the AutoSizeDropDownToBestFit property of the MultiColumnComboBoxElement is causing this trouble. My suggestion is to set it to false. And since by default the filtering operations are controlled by the AutoFilter property this is the best workaround I can provide you with at the moment due to the implementation of RadGridView.

    Let me know if there is anything else.

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