Sorting - Disable None

[Claude]

I want to toggle only between Ascending and Descending when the user clicks on the column header.  I do not want the None option.  Not sure what one would use the None option for anyway. That is not a sort.

 

 

[Stefan]

Hello Claude,

Thank you for writing.

The None sort option is quite often used, especially in scenarios where you have your have pre-sorted. However, one possible way to skip it is to override the Sort method of the header cell. Here is how to do that:

protected override void OnLoad(EventArgs e)
{
    base.OnLoad(e);

    AddGridSimple();
    radGridView1.CreateCell += radGridView1_CreateCell;

}

void radGridView1_CreateCell(object sender, GridViewCreateCellEventArgs e)
{
    if (e.CellType == typeof(GridHeaderCellElement))
    {
        e.CellType = typeof(MyHeaderCell);
    }
}

class MyHeaderCell : GridHeaderCellElement
{
    public MyHeaderCell(GridViewColumn column, GridRowElement row) :base(column,row)
    {

    }
    public override void Sort(RadSortOrder sortOrder)
    {
        if (sortOrder == RadSortOrder.None)
        {
            sortOrder = RadSortOrder.Ascending;
        }
        base.Sort(sortOrder);
    }

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

I hope that you find this information useful. Should you have any other questions, do not hesitate to contact us.

Regards,
Stefan
Telerik

 

 

[Abba]

I want the None option, but I do not have it.  I am on version 2013 Q3.  Was it put in after?  or am I doing something wrong?  If it was put in after, is there a way to have this functionality in my version?

 

Thanks,

[Stefan]

Hi Abba,

This functionality was added in Q2 2014. In your version to add it you need to create customer header row behavior. Here is an example:

RadGridView radGridView1 = new RadGridView();

public Form1()
{
    InitializeComponent();

    this.Controls.Add(radGridView1);
    radGridView1.Dock = DockStyle.Fill;

    DataTable table = new DataTable();
    table.Columns.Add("col1");
    table.Columns.Add("col2");
    table.Rows.Add("value1", "value1");
    table.Rows.Add("value2", "value2");

    radGridView1.DataSource = table;

    BaseGridBehavior gridBehavior = radGridView1.GridBehavior as BaseGridBehavior;
    gridBehavior.UnregisterBehavior(typeof(GridViewTableHeaderRowInfo));
    gridBehavior.RegisterBehavior(typeof(GridViewTableHeaderRowInfo), new MyHeaderRowBehavior());
}




class MyHeaderRowBehavior : GridHeaderRowBehavior
{
    GridCellElement mouseDownCellElement;
    public override bool OnMouseDown(MouseEventArgs e)
    {
        mouseDownCellElement = this.GridControl.ElementTree.GetElementAtPoint(e.Location) as GridCellElement;
        return base.OnMouseDown(e);
    }

    public override bool OnMouseUp(MouseEventArgs e)
    {
        GridHeaderCellElement cell = this.GridControl.ElementTree.GetElementAtPoint(e.Location) as GridHeaderCellElement;

        if (e.Button == MouseButtons.Left &&
            cell != null &&
            cell == mouseDownCellElement)
        {
            RadSortOrder sortOrder = cell.SortOrder;

            if (sortOrder == RadSortOrder.None)
            {
                sortOrder = RadSortOrder.Ascending;
            }
            else if (sortOrder == RadSortOrder.Ascending)
            {
                sortOrder = RadSortOrder.Descending;
            }
            else
            {
                sortOrder = RadSortOrder.None;
            }

            cell.Sort(sortOrder);
            return true;
        }
        else
        {
            return base.OnMouseUp(e);
        }
    }
}

I hope that you find this information useful. Should you have any other questions, do not hesitate to contact us.

Regards,
Stefan
Telerik

[Abba]

Thank you Stefan,

While this has added the functionality, it seems to have a small side effect:
When I resize a column, it is applying the sort to the column on the right.  Meaning if I have 2 columns (1 and 2).  When i drag the resize slider, it will then sort column 2.

It is not a big deal and I would be sacrifice this for the no sort.  But I am curious if there is way around.

And I appreciate your help in this thread and in the others.  You seem very knowledgeable on this control and great response time.  It is making using this control a pleasure.

[Stefan]

Hi Abba,

Indeed, this behavior occurs as the base functionality kicks in. Can you please try the following behavior and let me know how it works for you:

class MyHeaderRowBehavior : GridHeaderRowBehavior
{
    bool sortedDescending = false;

    public override bool OnMouseUp(MouseEventArgs e)
    {
        RadSortOrder saveOrder = RadSortOrder.None;
        GridHeaderCellElement cell = this.GridControl.ElementTree.GetElementAtPoint(e.Location) as GridHeaderCellElement;

        if (cell != null)
        {
            saveOrder = cell.SortOrder;
        }

        bool res = base.OnMouseUp(e);

        if (saveOrder != cell.SortOrder)
        {
            if (cell.SortOrder == RadSortOrder.Ascending)
            {
                if (sortedDescending)
                {
                    cell.Sort(RadSortOrder.None);
                    sortedDescending = false;
                }
                else
                {
                    return res;
                }
            }
            else if (cell.SortOrder == RadSortOrder.Descending)
            {
                sortedDescending = true;
                return res;
            }
        }

        return res;
    }
}

I am looking forward to your reply.

Regards,
Stefan
Telerik