/// <summary>
/// Adds the specified component to this scroll pane container.
/// If the scroll pane has an existing child component, that
/// component is removed and the new one is added. </summary>
/// <param name="comp"> the component to be added </param>
/// <param name="constraints"> not applicable </param>
/// <param name="index"> position of child component (must be <= 0) </param>
protected internal sealed override void AddImpl(Component comp, Object constraints, int index)
{
lock (TreeLock)
{
if (ComponentCount > 0)
{
Remove(0);
}
if (index > 0)
{
throw new IllegalArgumentException("position greater than 0");
}
if (!SunToolkit.isLightweightOrUnknown(comp))
{
base.AddImpl(comp, constraints, index);
}
else
{
AddToPanel(comp, constraints, index);
}
}
}
