DataGridView CellTemplate setting not working properly

Question

I try for hours to create templates for columns created dynamically. Here's the code (It's not from my main project but I simplified the code to reproduce my issue) :

First, I created a class containing the Column setting :

public class ColumnBLO
{
    public string foreColor { get; set; }
    public string backColor { get; set; }
    public string Label { get; set; }
}

Then here's the code for my main window :

        private Dictionary<string, DataGridView> dgViews;
    private List<ColumnBLO> columns;

    public Form1()
    {
        InitializeComponent();
    }

    private void Form1_Load(object sender, EventArgs e)
    {
        tabControl1.TabPages.Clear();
        tabControl1.TabPages.Add(new TabPage("laUNe"));

        //Simulating Format settings
        columns = new List<ColumnBLO>();
        columns.Add(new ColumnBLO { backColor = "Black", foreColor = "Black", Label = "one" });
        columns.Add(new ColumnBLO { backColor = "Blue", foreColor = "Blue", Label = "two" });
        columns.Add(new ColumnBLO { backColor = "Red", foreColor = "Red", Label = "three" });

        //Creating datagridviews and populate with data
        dgViews = new Dictionary<string, DataGridView>();
        DataGridView dgv = new DataGridView();

        DataTable dt = new DataTable("laTable");
        dt.Columns.Add("one");
        dt.Columns.Add("two");
        dt.Columns.Add("three");
        dt.Rows.Add("un", "deux", "trois");
        dt.Rows.Add("un", "dos", "tres");
        dt.Rows.Add("uno", "due", "tre");
        dgv.DataSource = dt;

        dgViews.Add("one", dgv);

        tabControl1.TabPages[0].Controls.Add(dgv);

        //Formatting
        foreach (DataGridViewColumn dgvcol in dgViews["one"].Columns)
        {
            ColumnBLO colB = columns.Where(x => x.Label == dgvcol.HeaderText).First();
            DataGridViewCell dgvc = new DataGridViewTextBoxCell();
            dgvc.Style.BackColor = Color.FromName(colB.backColor);
            dgvc.Style.ForeColor = Color.FromName(colB.foreColor);
            dgvcol.CellTemplate = dgvc;
        }

    }
}

When I execute this code, the formatting is not displayed, since I click on a header column (to sort the column), or if I invoke myself the Sort method.

I tried a lot of things like Refresh(), Invalidate() and InvalidateColumns() on the DGV but nothing's working...

If someone could help me ;-)

Answer 1

Replace your foreach loop with the following...

...

//Formatting
foreach(DataGridViewColumn dgvcol in dgViews["one"].Columns)
{
     ColumnBLO colB = columns.First(x => x.Label == dgvcol.HeaderText);
     dgvcol.DefaultCellStyle.BackColor = Color.FromName(colB.BackColor);
     dgvcol.DefaultCellStyle.ForeColor = Color.FromName(colB.ForeColor);
}

...

If You use DefaultCellStyle instead of CellStyle cells would be rendered by your template by default... Soulds like Captain Obvious )))