protected override void OnLayout(bool changed, int l, int t, int r, int b)
{
l = 0;
t = 0;
r = Width;
b = Height;
if (Header != null)
{
var headerHeight = Header.MeasuredHeight;
Header.Layout(l, t, r, headerHeight);
ItemTop = headerHeight;
Item.Layout(l, headerHeight, r, b);
}
else if (Divider != null)
{
Divider.SetBounds(l, t, r, DividerHeight);
ItemTop = DividerHeight;
Item.Layout(l, DividerHeight, r, b);
}
else
{
ItemTop = t;
Item.Layout(l, t, r, b);
}
}