private void comboBoxBackgroundColor_SelectedIndexChanged(object sender, EventArgs e)
{
string color = this.comboBoxBackgroundColor.SelectedItem.ToString();
this.panelBackgroundColor.BackColor = Color.FromName(color);
this.panelTextAttributes.BackColor = Color.FromName(color);
this.panelLineAttributes.BackColor = Color.FromName(color);
this.panelAreaPolygonColor.BackColor = Color.FromName(color);
this.pictureBox.BackColor = Color.FromName(this.comboBoxBackgroundColor.Text);
}