Hello, Dreyfus,
Yes, ViewRowFormatting event fires for all non-data rows including a new row. According to the provided information, it seems that you would like to detect which are the newly added rows and customize them in a formatting event.
If this is your requirement, I can suggest you to store information about which row is newly added by using the Tag property. The Tag property is of type object and can store any useful information about the row. Note that RadGridView offers the UserAddedRow event where you can store the information about the row. Then, in the ViewRowFormatting even you have access to the GridViwRowInfo through the event arguments e.RowElement.RowInfo and you can color the appropriate rows that are newly added. Please refer to the following code snippet that demonstrates this approach:
public Form1()
{
InitializeComponent();
this.radGridView1.ViewRowFormatting += this.RadGridView1_ViewRowFormatting;
this.radGridView1.UserAddedRow += this.RadGridView1_UserAddedRow;
DataTable dt = new DataTable();
dt.Columns.Add("Product ID", typeof(int));
dt.Columns.Add("Product Name", typeof(string));
dt.Columns.Add("Manufacturer", typeof(string));
dt.Columns.Add("Sales Representant", typeof(string));
dt.Rows.Add(15, "Wooden Table", "Molzano Italy", "Simonette Saylor");
dt.Rows.Add(22, "Glass Table", "Ovalia Germany", "Richter Strauss");
dt.Rows.Add(31, "Small Glass Table", "L'Ouruje France", "Fannie Duncan");
dt.Rows.Add(14, "White Leather Chair", "Spidea England", "Paolo Rossini");
dt.Rows.Add(25, "Black Leather Couch", "Procren Hungary", "Jaroslav Lokash");
dt.Rows.Add(16, "Red Leather Couch", "Pront Italy", "Hellena Shnaider ");
dt.Rows.Add(37, "Modern Design Chair", "Atech USA", "Silvester Williams");
this.radGridView1.DataSource = dt;
}
private void RadGridView1_UserAddedRow(object sender, GridViewRowEventArgs e)
{
GridViewRowInfo row = e.Row;
row.Tag = "new row";
}
private void RadGridView1_ViewRowFormatting(object sender, RowFormattingEventArgs e)
{
if ( (string)e.RowElement.RowInfo.Tag == "new row")
{
e.RowElement.DrawFill = true;
e.RowElement.BackColor = Color.LightSkyBlue;
e.RowElement.NumberOfColors = 1;
e.RowElement.ForeColor = Color.White;
}
else
{
e.RowElement.ResetValue(LightVisualElement.DrawFillProperty, ValueResetFlags.Local);
e.RowElement.ResetValue(LightVisualElement.BackColorProperty, ValueResetFlags.Local);
e.RowElement.ResetValue(LightVisualElement.NumberOfColorsProperty, ValueResetFlags.Local);
e.RowElement.ResetValue(LightVisualElement.ForeColorProperty, ValueResetFlags.Local);
}
}

I hope this helps. Should you have further questions I will be glad to help.
Regards,
Nadya
Progress Telerik
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