Drag & drop functionalities to swap column.

[Johny]

Hi Guys:

I’m using telerik almost one year…. this is really an excellent tools for rapid development. However I’m facing a little issues and I’m stuck I can’t resolved this. The issues is I have a grid with five column, the first column contain the serial number of each record, and now I want to add drag & drop functionalities to swap column. For example I select the column number 5 and drag and drop it into the column 2 so I the column will swap and reorder the serial number, the column 5 will be column 2 and column will be column 5. How can I achieve this? I need your help / any suggestion.

Regards,

Md. Marufuzzaman

[Martin Vasilev]

Hi Johny,

Thank you for writing.

The described behavior is not supported in RadGridView. However, in the new version Q2 2010 we have added a new way to access the drag and drop services in RadGridView that allows you to implement your requirement. Please consider the following code as an example:

RadGridViewDragDropService _ddService;
GridViewColumn _draggedColumn;
private void Form1_Load(object sender, EventArgs e)
{
    _ddService = this.radGridView1.GridViewElement.GetService<RadGridViewDragDropService>();
    _ddService.PreviewDragStart += new EventHandler<Telerik.WinControls.PreviewDragStartEventArgs>(_ddService_PreviewDragStart);
    _ddService.Stopping += new EventHandler<Telerik.WinControls.RadServiceStoppingEventArgs>(ddService_Stopping);
}
void _ddService_PreviewDragStart(object sender, Telerik.WinControls.PreviewDragStartEventArgs e)
{
    GridCellElement draggedCell = e.DragInstance as GridCellElement;
    if (draggedCell != null)
    {
        _draggedColumn = draggedCell.ColumnInfo;
    }
}
void ddService_Stopping(object sender, Telerik.WinControls.RadServiceStoppingEventArgs e)
{
    GridCellElement dropCell = _ddService.DropTarget as GridCellElement;
    if (_draggedColumn != null && dropCell != null)
    {
        GridViewDataColumn dropColumn = dropCell.ColumnInfo as GridViewDataColumn;
        SwapColumns(_draggedColumn as GridViewDataColumn, dropColumn);

    }
    e.Commit = false;
    _draggedColumn = null;
}
private void SwapColumns(GridViewDataColumn col1, GridViewDataColumn col2)
{
    this.radGridView1.BeginUpdate();
    int index1 = this.radGridView1.Columns.IndexOf(col1);
    int index2 = this.radGridView1.Columns.IndexOf(col2);
    this.radGridView1.Columns.Remove(col1);
    this.radGridView1.Columns.Remove(col2);
    this.radGridView1.Columns.Insert(index1, col2);
    this.radGridView1.Columns.Insert(index2, col1);
    this.radGridView1.EndUpdate();
}

Let me know if you have any additional questions.

Best wishes,
Martin Vasilev
the Telerik team