Dynamically Populated TableLayoutPanel Performance Degredation

Question

I have a user control that contains a 2-column TableLayoutPanel and accepts commands to dynamically add rows to display details of an item selected in a separate control. So, the user will select a row in the other control (a DataGridView), and in the SelectedItemChanged event handler for the DataGridView I clear the detail control and then regenerate all the rows for the new selected item (which may have a totally different detail display from the previously selected item). This works great for a while. But if I keep moving from one selected item to another for quite a long time, the refreshes become VERY slow (3-5 seconds each). That makes it sound like I'm not disposing everything properly, but I can't figure out what I'm missing. Here's my code for clearing the TableLayoutPanel:

private readonly List<Control> controls;

public void Clear()
{
    detailTable.Visible = false;
    detailTable.SuspendLayout();
    SuspendLayout();
    detailTable.RowStyles.Clear();
    detailTable.Controls.Clear();
    DisposeAndClearControls();
    detailTable.RowCount = 0;
    detailTable.ColumnCount = 2;
}

private void DisposeAndClearControls()
{
    foreach (Control control in controls)
    {
        control.Dispose();
    }
    controls.Clear();
}

And once I get finished loading up all the controls I want into the TableLayoutPanel for the next detail display here's what I call:

public void Render()
{
    detailTable.ResumeLayout(false);
    detailTable.PerformLayout();
    ResumeLayout(false);
    detailTable.Visible = true;
}

I'm not using anything but labels (and a TextBox very rarely) inside the TableLayoutPanel, and I add the Labels and TextBoxes to the controls list (referenced in DisposeAndClearControls()) when I create them. I tried just iterating over detailTable.Controls and disposing them that way, but it seemed to miss half the controls (determined by stepping through it in the debugger). This way I know I get them all.

I'd be interested in any suggestions to improve drawing performance, but particularly what's causing the degradation over multiple selections.

Answer 1

Just use a custom control that inherits from TableLayoutPanel and set the DoubleBuffered property on true, works great... especially when you dynamically add or remove rows.

public CustomLayout()
{
   this.DoubleBuffered = true;
   InitializeComponent();
}