BindingList<Item> items = new BindingList<Item>();

public Form1()
{
    InitializeComponent();

    for (int i = 0; i < 20; i++)
    {
        items.Add(new Item(i % 4, "Item" + i, "Type" + i % 2));
    }
    this.radGridView1.DataSource = items;
    this.radGridView1.AutoSizeColumnsMode = Telerik.WinControls.UI.GridViewAutoSizeColumnsMode.Fill;
}

public class Item
{
    public int Id { get; set; }

    public string Name { get; set; }

    public string Type { get; set; }

    public Item(int id, string name, string type)
    {
        this.Id = id;
        this.Name = name;
        this.Type = type;
    }
}

private void radButton1_Click(object sender, EventArgs e)
{
    items.Insert(0, new Item(2, "Test", "Type0"));
}

WORKAROUND I:

GridViewSynchronizationService.SuspendEvent(this.radGridView1.MasterTemplate, KnownEvents.CurrentChanged);
Item item = new Item(2, "Test", "Type0");
items.Insert(0, item);
GridViewSynchronizationService.ResumeEvent(this.radGridView1.MasterTemplate, KnownEvents.CurrentChanged);

foreach (GridViewRowInfo row in this.radGridView1.Rows)
{
    if (row.DataBoundItem == item)
    {
        this.radGridView1.CurrentRow = row;

        break;
    }
}



WORKAROUND II:

this.radGridView1.Rows.CollectionChanged += Rows_CollectionChanged;
this.radGridView1.GroupExpanding+=radGridView1_GroupExpanding;

List<GridViewRowInfo> expandedGroups = new List<GridViewRowInfo>();

private void radGridView1_GroupExpanding(object sender, GroupExpandingEventArgs e)
{
    if (!e.IsExpanded && shouldCollapse)
    {
        expandedGroups.Add(e.DataGroup.GroupRow);
    }
}

bool shouldCollapse = false;

private void radButton1_Click(object sender, EventArgs e)
{
    shouldCollapse = true;
    items.Insert(0, new Item(2, "Test", "Type0"));
}

private void Rows_CollectionChanged(object sender, Telerik.WinControls.Data.NotifyCollectionChangedEventArgs e)
{
    if (e.Action == Telerik.WinControls.Data.NotifyCollectionChangedAction.Add)
    {
        this.radGridView1.CurrentRow = e.NewItems[0] as GridViewRowInfo;
        this.radGridView1.CurrentRow.IsSelected = true;
        GridViewRowInfo parent = this.radGridView1.CurrentRow.Parent as GridViewRowInfo;
        if (parent != null)
        {
            parent.IsExpanded = true;
        }

        if (shouldCollapse)
        {
            shouldCollapse = false;
            foreach (GridViewRowInfo r in expandedGroups)
            {
                if (!ContainsParentRow(parent, r))
                {
                    r.IsExpanded = false;
                }
            }
            expandedGroups.Clear();
        }
    }
}

private bool ContainsParentRow(GridViewRowInfo parent, GridViewRowInfo r)
{
    GridViewGroupRowInfo group = r as GridViewGroupRowInfo;
    if (group != null)
    {
        foreach (GridViewRowInfo childRow in group.ChildRows)
        {
            return ContainsParentRow(parent, childRow);
        }
    }

    return parent == r.Parent;
}

Workaround: set up the templates from code, http://www.telerik.com/help/winforms/gridview-overview.html

To reproduce:

1. Add a RadTreeView and a RadGridView 
2. Use the following code snippet.
3. Select a node from the RadtreeView.
4. Activate the editor for the new row in RadGridView.
5. While the grid editor is active, select a new node in the tree.

public Form1()
{
    InitializeComponent();
    this.radGridView1.MasterTemplate.AddNewBoundRowBeforeEdit = true;
}

public class ClassA 
{
    public int Id { get; set; }

    public string Name { get; set; }

    public string Grade { get; set; }
   
    public ClassA()
    {
    }

    public ClassA(int id, string name, string grade)
    {
        this.Id = id;
        this.Name = name;
        this.Grade = grade;
    }
}

public class ClassB
{
    public int NewID { get; set; }

    public string FirstName { get; set; }

    public string LastName { get; set; }

    public ClassB()
    {
    }

    public ClassB(int id, string firstName, string lastName)
    {
        this.NewID = id;
        this.FirstName = firstName;
        this.LastName = lastName;
    }
}

private void radTreeView1_SelectedNodeChanged(object sender, Telerik.WinControls.UI.RadTreeViewEventArgs e)
{
    if (radGridView1.DataSource is BindingList<ClassA>)
    { 
        this.radGridView1.Columns.Clear();
        this.radGridView1.DataSource = null;
        BindingList<ClassB> list = new BindingList<ClassB>() { new ClassB(1, "John", "Wick") };
        this.radGridView1.DataSource = list;
    }
    else
    {
        this.radGridView1.DataSource = null;
        BindingList<ClassA> list = new BindingList<ClassA>() { new ClassA(1,"John", "A+") };
        this.radGridView1.Columns.Clear();
        this.radGridView1.DataSource = list;
    }
}

Workaround:  this.radGridView1.MasterTemplate.AddNewBoundRowBeforeEdit = false;

Workaround: create a custom GridCheckBoxHeaderCellElement and override the Attach method

public class MyGridCheckBoxHeaderCellElement : GridCheckBoxHeaderCellElement
{

	public MyGridCheckBoxHeaderCellElement(GridViewColumn column, GridRowElement row) : base(column, row)
	{
	}

	protected override Type ThemeEffectiveType {
		get { return typeof(GridHeaderCellElement); }
	}

	public override void Attach(GridViewColumn data, object context)
	{
		if (((GridViewCheckBoxColumn)data).EnableHeaderCheckBox) {
			base.Attach(data, context);
		} else {
			this.CheckBox.Visibility = Telerik.WinControls.ElementVisibility.Collapsed;
		}
	}
}

public Form1()
{
        InitializeComponent();
	this.radGridView1.CreateCell += radGridView1_CreateCell;
}


private void radGridView1_CreateCell(object sender, Telerik.WinControls.UI.GridViewCreateCellEventArgs e)
{
	if (e.CellType == typeof(GridCheckBoxHeaderCellElement)) {
		e.CellElement = new MyGridCheckBoxHeaderCellElement(e.Column, e.Row)
	}
}

To reproduce:
private RadGridView radGridView1;

public Form1()
{
    InitializeComponent();
    radGridView1 = new RadGridView() { Dock = DockStyle.Fill };
    Controls.Add(radGridView1);

    List<Item> items = new List<Item>();
    for (int i = 0; i < 10; i++)
    {
        items.Add(new Item(i, "Item" + i, DateTime.Now.AddDays(i)));
    }
    radGridView1.AutoGenerateColumns = true;
    this.radGridView1.DataSource = items;
    this.radGridView1.AutoSizeColumnsMode = GridViewAutoSizeColumnsMode.Fill;
    this.radGridView1.EnableFiltering = true;

    this.radGridView1.CustomFiltering += radGridView1_CustomFiltering;
    radGridView1.EnableCustomFiltering = true;
}

void radGridView1_CustomFiltering(object sender, GridViewCustomFilteringEventArgs e)
{
    e.Handled = false;
    e.Visible = true;

    var item = (Item)e.Row.DataBoundItem;

    if (item == null)
        return;

    if (item.Name.EndsWith("Item"))
    {
        e.Handled = true;
        e.Visible = false;
    }
}

public class Item
{
    public int Id { get; set; }

    public string Name { get; set; }

    public Nullable<DateTime> Date { get; set; }

    public Item(int id, string name, Nullable<DateTime> date)
    {
        this.Id = id;
        this.Name = name;
        this.Date = date;
    }
}


Workaround:

private void radGridView1_CellEndEdit(object sender, GridViewCellEventArgs e)
{
    this.radGridView1.MasterTemplate.Refresh();
}

To reproduce:
Me.RadGridView1.MultiSelect = True

Private Sub RadGridView1_CellFormatting(sender As Object, e As Telerik.WinControls.UI.CellFormattingEventArgs) _
Handles RadGridView1.CellFormatting
    If e.Row.IsSelected Then
        e.CellElement.BackColor = Color.LimeGreen
        e.CellElement.DrawFill = True
        e.CellElement.GradientStyle = Telerik.WinControls.GradientStyles.Solid
    Else
        e.CellElement.ResetValue(LightVisualElement.BackColorProperty, ValueResetFlags.Local)
        e.CellElement.ResetValue(LightVisualElement.DrawFillProperty, ValueResetFlags.Local)
        e.CellElement.ResetValue(LightVisualElement.GradientStyleProperty, ValueResetFlags.Local)
    End If
End Sub

Step 1: Select a few rows with the mouse click in combination with the CTRL key.
Step 2: The rows are selected correctly and the desired green back color is applied. Release the CTRL Key.
Step 3: Click with the mouse on a different row in the grid.

Result: All previously selected rows but the last current row keep the green back color.

Workaround:

Sub New()
    InitializeComponent()
 
    Me.RadGridView1.MultiSelect = True
    AddHandler Me.RadGridView1.SelectionChanging, AddressOf SelectionChanging
    AddHandler Me.RadGridView1.SelectionChanged, AddressOf SelectionChanged
 
End Sub
 
Private Sub RadGridView1_CellFormatting(sender As Object, e As Telerik.WinControls.UI.CellFormattingEventArgs) _
Handles RadGridView1.CellFormatting
    e.CellElement.DrawFill = True
    e.CellElement.GradientStyle = Telerik.WinControls.GradientStyles.Solid
    If e.Row.IsSelected Then
        e.CellElement.BackColor = Color.LimeGreen
    Else
        e.CellElement.BackColor = Color.Yellow
    End If
End Sub
Private Sub SelectionChanged(sender As Object, e As EventArgs)
    For Each r As GridViewRowInfo In selectedRows
        r.InvalidateRow()
    Next
    selectedRows.Clear()
End Sub
 
Dim selectedRows As New List(Of GridViewRowInfo)
Private Sub SelectionChanging(sender As Object, e As GridViewSelectionCancelEventArgs)
    For Each r As GridViewRowInfo In Me.RadGridView1.SelectedRows
        selectedRows.Add(r)
    Next
End Sub

To reproduce:

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

    this.radGridView1.DataSource = this.customersBindingSource;
    this.radGridView1.AutoSizeColumnsMode = Telerik.WinControls.UI.GridViewAutoSizeColumnsMode.Fill;

    foreach (GridViewColumn col in this.radGridView1.Columns)
    {
        col.MinWidth = 100;
    }
    
    ColumnGroupsViewDefinition view = new ColumnGroupsViewDefinition();
    view.ColumnGroups.Add(new GridViewColumnGroup("Customer Contact"));
    view.ColumnGroups.Add(new GridViewColumnGroup("Details"));
    view.ColumnGroups[1].Groups.Add(new GridViewColumnGroup("Address"));
    view.ColumnGroups[1].Groups.Add(new GridViewColumnGroup("Contact"));
    view.ColumnGroups[0].Rows.Add(new GridViewColumnGroupRow());
    view.ColumnGroups[0].Rows[0].Columns.Add(this.radGridView1.Columns["CompanyName"]);
    view.ColumnGroups[0].Rows[0].Columns.Add(this.radGridView1.Columns["ContactName"]);
    view.ColumnGroups[0].Rows[0].Columns.Add(this.radGridView1.Columns["ContactTitle"]);

    view.ColumnGroups[1].Groups[0].Rows.Add(new GridViewColumnGroupRow());
    view.ColumnGroups[1].Groups[0].Rows[0].Columns.Add(this.radGridView1.Columns["Address"]);
    view.ColumnGroups[1].Groups[0].Rows[0].Columns.Add(this.radGridView1.Columns["City"]);
    view.ColumnGroups[1].Groups[0].Rows[0].Columns.Add(this.radGridView1.Columns["Country"]);

    view.ColumnGroups[1].Groups[1].Rows.Add(new GridViewColumnGroupRow());
    view.ColumnGroups[1].Groups[1].Rows[0].Columns.Add(this.radGridView1.Columns["Phone"]);
    view.ColumnGroups[1].Groups[1].Rows[0].Columns.Add(this.radGridView1.Columns["Fax"]);
    radGridView1.ViewDefinition = view;
}

Please refer to the attached gif file illustrating the behavior when no ColumnGroupsViewDefinition is applied. The horizontal scroll-car should appear as well when the grid's width is less than the total MinWidth of all columns in case of ColumnGroupsViewDefinition.

Workaround: use GridViewAutoSizeColumnsMode.None and handle the RadGridView.SizeChanged event where you can adjust manually the Width of the visible columns on a way to simulate GridViewAutoSizeColumnsMode.Fill. Here is a sample approach:

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

    this.radGridView1.DataSource = this.customersBindingSource;
    this.radGridView1.AutoSizeColumnsMode = Telerik.WinControls.UI.GridViewAutoSizeColumnsMode.None;

    foreach (GridViewColumn col in this.radGridView1.Columns)
    {
        col.MinWidth = 100;
    }

    ColumnGroupsViewDefinition view = new ColumnGroupsViewDefinition();
    view.ColumnGroups.Add(new GridViewColumnGroup("Customer Contact"));
    view.ColumnGroups.Add(new GridViewColumnGroup("Details"));
    view.ColumnGroups[1].Groups.Add(new GridViewColumnGroup("Address"));
    view.ColumnGroups[1].Groups.Add(new GridViewColumnGroup("Contact"));
    view.ColumnGroups[0].Rows.Add(new GridViewColumnGroupRow());
    view.ColumnGroups[0].Rows[0].Columns.Add(this.radGridView1.Columns["CompanyName"]);
    view.ColumnGroups[0].Rows[0].Columns.Add(this.radGridView1.Columns["ContactName"]);
    view.ColumnGroups[0].Rows[0].Columns.Add(this.radGridView1.Columns["ContactTitle"]);

    view.ColumnGroups[1].Groups[0].Rows.Add(new GridViewColumnGroupRow());
    view.ColumnGroups[1].Groups[0].Rows[0].Columns.Add(this.radGridView1.Columns["Address"]);
    view.ColumnGroups[1].Groups[0].Rows[0].Columns.Add(this.radGridView1.Columns["City"]);
    view.ColumnGroups[1].Groups[0].Rows[0].Columns.Add(this.radGridView1.Columns["Country"]);

    view.ColumnGroups[1].Groups[1].Rows.Add(new GridViewColumnGroupRow());
    view.ColumnGroups[1].Groups[1].Rows[0].Columns.Add(this.radGridView1.Columns["Phone"]);
    view.ColumnGroups[1].Groups[1].Rows[0].Columns.Add(this.radGridView1.Columns["Fax"]);
    radGridView1.ViewDefinition = view;

    radGridView1.SizeChanged += radGridView1_SizeChanged;
}

private void radGridView1_SizeChanged(object sender, EventArgs e)
{
    int totalMinimumWidth = 0;
    int columnsCount = ColumnsCountWidth(out totalMinimumWidth);
    int delta = this.radGridView1.Width - totalMinimumWidth;
    AdjustColumnWidth(delta / columnsCount);
}

private void AdjustColumnWidth(int widthToAdd)
{
    ColumnGroupsViewDefinition view = this.radGridView1.ViewDefinition as ColumnGroupsViewDefinition;
    if (view == null)
    {
        return;
    }

    foreach (GridViewColumnGroup group in view.ColumnGroups)
    {
        AdjustColumnsInGroup(widthToAdd, group);
    }
}

private void AdjustColumnsInGroup(int widthToAdd, GridViewColumnGroup group)
{
    if (group.Groups.Count == 0)
    {
        foreach (GridViewColumnGroupRow row in group.Rows)
        {
            foreach (GridViewColumn col in row.Columns)
            {
                col.Width += widthToAdd;
            }
        }
    }
    else
    {
        foreach (GridViewColumnGroup g in group.Groups)
        {
            AdjustColumnsInGroup(widthToAdd, g);
        }
    }
}

private int ColumnsCountWidth(out int totalMinWidth)
{
    int columnsCount = 0;
    totalMinWidth = 0;
    ColumnGroupsViewDefinition view = this.radGridView1.ViewDefinition as ColumnGroupsViewDefinition;
    if (view == null)
    {
        return this.radGridView1.Columns.Count;
    }

    foreach (GridViewColumnGroup group in view.ColumnGroups)
    {
        columnsCount = IterateGroups(columnsCount, group, ref totalMinWidth);              
    }
    return columnsCount;
}

private static int IterateGroups(int columnsCount, GridViewColumnGroup group, ref int totalMinWidth)
{
    int count = columnsCount;
    if (group.Groups.Count == 0)
    {
        foreach (GridViewColumnGroupRow row in group.Rows)
        {
            count += row.Columns.Count;
            foreach (GridViewColumn col in row.Columns)
            {
                totalMinWidth += col.Width;
            }
        }
    }
    else
    {
        foreach (GridViewColumnGroup g in group.Groups)
        {
            count = IterateGroups(count, g, ref totalMinWidth);
        }
    }
    return count;
}

Please refer to the attached screenshot.

Workaround: either select the RadGridView node in the Property Builder, or use the VS design time or control Smart Tag to set DataSource

To reproduce :
- Set conditional formatting for all grid cells.
- Iterate all grid cells and set their value.

Workaround:
Use Begin/End update block.

To reproduce:
- Add grid with several columns and set their AllowResize property to false.
- Set the FitWidthMode to FitPageWidth.
- Print the grid and you will notice that some of the columns are cut off.
 
Workaround:
- Set the AllowResize property to true before printing.

To reproduce:
- Enter a value in the search row (make sure you will have several results)
- Enter a letter in the filtering row. The filetring row will lose the focus.

Workaround:
public class MyGridViewSearchRowInfo : GridViewSearchRowInfo
{
    public MyGridViewSearchRowInfo(GridViewInfo viewInfo) : base(viewInfo)
    {
    }

    public override void SelectNextSearchResult()
    {
        GridViewSystemRowInfo systemRow = this.ViewTemplate.MasterTemplate.CurrentRow as GridViewSystemRowInfo;

        if (systemRow != null && this.ViewTemplate.MasterTemplate.Owner.EditorManager.IsInEditMode)
        {
            return;
        }
        base.SelectNextSearchResult();
    }
}

//change the default row like this
void radGridView1_CreateRowInfo(object sender, GridViewCreateRowInfoEventArgs e)
{
    if (e.RowInfo is GridViewSearchRowInfo)
    {
        e.RowInfo = new MyGridViewSearchRowInfo(e.ViewInfo);
    }
}

To reproduce: following the illustrated steps: http://screencast.com/t/D2TCpU2zo

Workaround: set up the hierarchy programmatically.

To reproduce:

public Form1()
{
    InitializeComponent();

    GridViewCheckBoxColumn checkBoxColumn = new GridViewCheckBoxColumn("Select");
    checkBoxColumn.EnableHeaderCheckBox = true;
    radGridView1.MasterTemplate.Columns.Insert(0, checkBoxColumn);

    for (int i = 0; i < 10; i++)
    {
        this.radGridView1.Rows.Add(false);
    }
    this.radGridView1.AutoSizeColumnsMode = GridViewAutoSizeColumnsMode.Fill;

    this.radGridView1.MultiSelect = true;
    this.radGridView1.HeaderCellToggleStateChanged += radGridView1_HeaderCellToggleStateChanged;
}

private void radGridView1_HeaderCellToggleStateChanged(object sender, GridViewHeaderCellEventArgs e)
{
    if (e.State.ToString() == "On")
        this.radGridView1.SelectAll();
    else
        this.radGridView1.ClearSelection();
}


Workaround 1:
private void radGridView1_HeaderCellToggleStateChanged(object sender, GridViewHeaderCellEventArgs e)
{
    bool selected = e.State.ToString() == "On";

    foreach (GridViewRowInfo r in this.radGridView1.Rows)
    {
        r.IsSelected = selected;
    }
}

Workaround 2:

private void radGridView1_MouseUp(object sender, MouseEventArgs e)
{
    RadCheckBoxElement el = this.radGridView1.ElementTree.GetElementAtPoint(e.Location) as RadCheckBoxElement;
    if (el!=null)
    {
        GridCheckBoxHeaderCellElement headerCell = el.Parent as GridCheckBoxHeaderCellElement;
        bool selected = el.ToggleState == Telerik.WinControls.Enumerations.ToggleState.On;
        if (headerCell!=null)
        {
            if (selected)
            {
                this.radGridView1.SelectAll();
            }
            else
            {
                this.radGridView1.ClearSelection();
            }
        }
    }
}

To reproduce:

GridViewMultiComboBoxColumn supplierColumn = new GridViewMultiComboBoxColumn();
supplierColumn.SyncSelectionWithText = true;
supplierColumn.Name = "SupplierColumn";
supplierColumn.HeaderText = "Supplier";
supplierColumn.DropDownStyle = Telerik.WinControls.RadDropDownStyle.DropDown;
supplierColumn.AutoCompleteMode = AutoCompleteMode.Append;
supplierColumn.DataSource = this.suppliersBindingSource;
supplierColumn.ValueMember = "SupplierID";
supplierColumn.DisplayMember = "ContactName";
supplierColumn.FieldName = "SupplierID";
supplierColumn.Width = 200;
this.radGridView1.Columns.Add(supplierColumn);

Select the new row and try to enter some text that is not valid and press Enter. You will notice the new row is added with the last valid auto-completed value.

Workaround: cancel the UserAddingRow event if the entered text is not valid.

To reproduce:

this.radGridView1.DataSource = this.ordersBindingSource;
GridViewDateTimeColumn col = this.radGridView1.Columns["OrderDate"] as GridViewDateTimeColumn;
col.ExcelExportType = DisplayFormatType.GeneralDate;
col.ExcelExportFormatString = "dd-MMM-yy";

private void radButton1_Click(object sender, EventArgs e)
{
    SpreadExport spreadExporter = new SpreadExport(radGridView1);
    spreadExporter.RunExport(@"..\..\..\exportedFileQ12015.xlsx");

    Process.Start(@"..\..\..\exportedFileQ12015.xlsx");
}

Workaround:

private void radButton1_Click(object sender, EventArgs e)
{
    SpreadExport spreadExporter = new SpreadExport(radGridView1);
    spreadExporter.CellFormatting += spreadExporter_CellFormatting;
    spreadExporter.RunExport(@"..\..\..\exportedFileQ12015.xlsx");

    Process.Start(@"..\..\..\exportedFileQ12015.xlsx");
}

private void spreadExporter_CellFormatting(object sender, Telerik.WinControls.UI.Export.SpreadExport.CellFormattingEventArgs e)
{
    if (e.GridColumnIndex == 3 && e.GridCellInfo.Value is DateTime)
    {
        CellValueFormat cvf = new CellValueFormat("dd-MMM-yy");
        e.CellSelection.SetFormat(cvf);
    }
}

To reproduce:

1. Populate RadGridView with data
2. Export the grid by using the SpreadExport
3. Open the produce Excel file and select  some cells to generate a chart in Excel. You will notice that it is not possible to create a complete chart with the selected data.

Workaround: use the ExportToExcelML >> http://www.telerik.com/help/winforms/gridview-exporting-data-export-to-excel-via-excelml-format.html 

To reproduce:
- Set the cell's BackColor in an entire column.
- Set the cell's Forecolor in another column. 
- Change the grid size to the columns are hidden and then shown again.

Workaround:
Change similar properties for all the cells where the Style property is used or use CellFormatting.