Please run the attached sample project and navigate with the left/right arrows as it is demonstrated in the gif file.

Please use the following code snippet and click the filter button for the first column in the virtual grid. You will notice that the default menu is shown:

        RadContextMenu menu = new RadContextMenu();
        public RadForm1()
        {
            InitializeComponent();
            RadDateTimePicker aDateTimePicker = new RadDateTimePicker();
            RadMenuItem theMenuItem = new RadMenuItem();
            theMenuItem.MinSize = new Size(200, 30);
            RadHostItem theHostItem = new RadHostItem(aDateTimePicker);
            theMenuItem.Children.Add(theHostItem); 
            menu.Items.Add(theMenuItem);
            this.radVirtualGrid1.RowCount = 50;
            this.radVirtualGrid1.ColumnCount = 5;
            this.radVirtualGrid1.CellValueNeeded+=radVirtualGrid1_CellValueNeeded;

            this.radVirtualGrid1.AllowFiltering = true;
            this.radVirtualGrid1.ContextMenuOpening+=radVirtualGrid1_ContextMenuOpening;
        }

        private void radVirtualGrid1_ContextMenuOpening(object sender, VirtualGridContextMenuOpeningEventArgs e)
        {
            int i;
            string theMenuItemText;

            if (e.RowIndex == -3 && e.ColumnIndex < 1)
            {
                e.ContextMenu = menu.DropDown; 
            }
        }

        private void radVirtualGrid1_CellValueNeeded(object sender, VirtualGridCellValueNeededEventArgs e)
        {
            e.Value = Guid.NewGuid().ToString();
        }

It is difficult to replicate the issue and it is not always reproduced. When using the splitter between columns[1] and columns[2]  to resize column[1] I found out that releasing the mouse button doesn't cause the splitter to be released, even when clicking on the grid. It seems to work ok once or twice but once it fails then keeps failing.

Workaround:
        private void radVirtualGrid1_MouseUp(object sender, MouseEventArgs e)
        {
            if (e.Button == System.Windows.Forms.MouseButtons.Left)
            {
                this.radVirtualGrid1.Cursor = Cursors.Default;
            }
        }

Hi,

I have a problem with the expansion of the last row.

After Row Expanding and Row Collapsing the last or second last row, the last row is not visible because it seems that there I some kind of lock on the scrollbar : it doesn’t scroll down neither with the mouse wheel nor with the button so it is not possible to move on the last row.

If instead you scroll up and then down the row became visible again.

In the attached example project.

Regards

To reproduce: open the VirtualGrid >> First Look example in QSF and follow the steps:

1) I have a virtual grid which has both vertical and horizontal scroll bars.

2) Scroll to the very bottom of the grid

3) Select the last row

4) Scroll all the way to the right

At this moment the selected row disappears from the view. While scrolling horizontally the vertical scrollbar jumps several rows above although it seems scrolled to the bottom. 

To reproduce: 

Set the RowSpacing to 10. Press down until the last cell is selected. The view is not scrolled down. 

Hello, we have found another small bug of the RadVirtualGrid control.

When paging is enabled on child view, one of the component of the paging panel overlap whit is parent.

I attach source code and screenshot.

Thanks in advance.

To reproduce: please refer to the attached gif file. The CellClick is not fired for the child rows that belong to columns that exceed the width of the parent template.

Workaround: set the AutoSizeColumnsMode property to Fill.

this.radVirtualGrid1.AutoSizeColumnsMode = Telerik.WinControls.UI.VirtualGridAutoSizeColumnsMode.Fill;

When you setup a hierarchical RadVirtualGrid and set the UseScrollbarsInHierarchy property to false and use VirtualGridAutoSizeColumnsMode.Fill for the child template, you expect that the column's width is calculated according to the total width of the respective template. Hence, if you shrink or enlarge the grid, the columns will shrink/enlarge respectively. However, if you double click the resize cursor between the column headers you will notice that the best-fit action is performed over the column and its width is adjusted. However, the VirtualGridAutoSizeColumnsMode.Fill setting is not respected and you either can't see all the columns, or you obtain some empty space if the column doesn't need much space. 

To reproduce: open the Demo application >> VirtualGrid >> First Look example. Follow the steps illustrated in the attached gif file. You will notice that when you expand a row, the "-" sign is show for a second and then it is returned to "+" although the row is still expanded. 

Workaround:
            this.radVirtualGrid1.CellFormatting += radVirtualGrid1_CellFormatting;
            this.radVirtualGrid1.RowExpanded += radVirtualGrid1_RowExpanded;
            this.radVirtualGrid1.RowCollapsed += radVirtualGrid1_RowCollapsed;



        private void radVirtualGrid1_RowCollapsed(object sender, VirtualGridRowExpandedEventArgs e)
        {
            if (expandedState.ContainsKey(e.RowIndex))
            {
                expandedState[e.RowIndex] = !expandedState[e.RowIndex];
            }
           
            this.radVirtualGrid1.TableElement.SynchronizeRow(e.RowIndex, true);
        }

        Dictionary<int, bool> expandedState = new Dictionary<int, bool>();

        private void radVirtualGrid1_RowExpanded(object sender, VirtualGridRowExpandedEventArgs e)
        {
            if (!expandedState.ContainsKey(e.RowIndex))
            {
                expandedState.Add(e.RowIndex, false);
            }
            expandedState[e.RowIndex] = !expandedState[e.RowIndex];
            this.radVirtualGrid1.TableElement.SynchronizeRow(e.RowIndex, true);
        }

        private void radVirtualGrid1_CellFormatting(object sender, Telerik.WinControls.UI.VirtualGridCellElementEventArgs e)
        {
            VirtualGridIndentCellElement indentCell = e.CellElement as VirtualGridIndentCellElement;
            if (indentCell != null)
            {
                if (expandedState.ContainsKey(e.CellElement.RowIndex) && expandedState[e.CellElement.RowIndex] == true)
                {
                    indentCell.ExpanderItem.SignImage = Properties.Resources.chevron_up;
                }
                else
                {
                    indentCell.ExpanderItem.SignImage = Properties.Resources.chevron_down;
                }
            }

        }

To reproduce: if you set the TableElement.RowHeight property, it affects the header row as well, but not all cells. As a result the header row overlaps the new row.

Workaround: set the TableElement.HeaderRowHeight as well.

  this.radVirtualGrid1.TableElement.HeaderRowHeight = 50;

To reproduce: use the following code snippet. Navigate to the last page and press the button to clear the rows. You will notice that the current page index remains 10 although no rows are available in the grid

        public RadForm1()
        {
            InitializeComponent();

            this.radVirtualGrid1.RowCount = 1000;
            this.radVirtualGrid1.ColumnCount = 5;
            this.radVirtualGrid1.CellValueNeeded += radVirtualGrid1_CellValueNeeded;

            this.radVirtualGrid1.EnablePaging = true;
        }

        private void radVirtualGrid1_CellValueNeeded(object sender, Telerik.WinControls.UI.VirtualGridCellValueNeededEventArgs e)
        {
            e.Value = "Item" + e.RowIndex + "." + e.ColumnIndex;
        }

        private void radButton1_Click(object sender, EventArgs e)
        {
            this.radVirtualGrid1.RowCount = 0;
            this.radVirtualGrid1.ColumnCount = 5; 
        }

Workaround:  this.radVirtualGrid1.VirtualGridElement.FindDescendant<VirtualGridPagingPanelElement>().PageNumberTextBox.Text = "1";

To reproduce: run the sample project and try to resize some of the columns.

RadVirtualGrid has 10 columns and 500 rows. You will notice the laggind while resizing the columns. Actually the number of the visible cells remains the same after the column's resizing. However, the CellValueNeeded event keeps firing.

A newly created grid has its CurrentCell property initialized to Nothing. Pressing [PageDown] or any other key that causes scrolling will crash.

Steps to Reproduce:
1. Launch application
2. Press [PageDown]

 Sub New() 
        InitializeComponent()

        Me.RadVirtualGrid1.ColumnCount = 50
        Me.RadVirtualGrid1.RowCount = 100
        AddHandler Me.RadVirtualGrid1.CellValueNeeded, AddressOf RadVirtualGrid1_CellValueNeeded
    End Sub

    Private Sub RadVirtualGrid1_CellValueNeeded(sender As Object, e As Telerik.WinControls.UI.VirtualGridCellValueNeededEventArgs)
        e.Value = e.ColumnIndex
    End Sub

Workaround: 

Me.RadVirtualGrid1.CurrentCell = New Telerik.WinControls.UI.VirtualGridCellInfo(0, 0, Me.RadVirtualGrid1.MasterViewInfo)

I miss grouping functionality in VirtualGrid. In my opinion, the following process would be conceivable:
1. user interaction triggers an event - e. g. GroupChanged (similar to FilterChanged).
2. This event determines all available groups and returns them to the VirtualGrid. 
3. if the user expand a group > a second event is fired - and returns all matching data rows.

To reproduce:
- Enable the paging and add 1000 rows.
- Press Ctrl + End
- An exception is thrown.

Workaround:

radVirtualGrid1.VirtualGridElement.InputBehavior = new MyBehavior(radVirtualGrid1.VirtualGridElement);

class MyBehavior : VirtualGridInputBehavior
{
    public MyBehavior(RadVirtualGridElement element) : base(element)
    {

    }
    protected override bool HandleEndKey(KeyEventArgs keys)
    {
        this.GridElement.PageIndex = this.GridElement.TotalPages - 1;
      
        return true;
        //return base.HandleEndKey(keys);
    }
}

The attached gif file illustrates how to reproduce the problem with the Demo application.