/// <inheritdoc/>
protected override void OnArrange(Vector2F position, Vector2F size)
{
// Update X or Y of the thumb to slide it to the correct position.
if (_thumb != null)
{
float value = Value;
float minimum = Minimum;
float maximum = Maximum;
float range = maximum - minimum;
Vector4F padding = Padding;
if (Orientation == Orientation.Horizontal)
{
float contentWidth = ActualWidth - padding.X - padding.Z;
// ViewPortSize determines thumb width.
float thumbWidth = contentWidth * ViewportSize;
if (thumbWidth < _thumb.MinWidth)
{
thumbWidth = _thumb.MinWidth;
}
else if (thumbWidth > _thumb.MaxWidth)
{
thumbWidth = _thumb.MaxWidth;
}
_thumb.Width = thumbWidth;
_thumb.Measure(new Vector2F(float.PositiveInfinity));
// Compute movement range of thumb center.
contentWidth = ActualWidth - padding.X - padding.Z - thumbWidth;
float thumbCenterPosition = contentWidth / range * (value - Minimum);
if (Numeric.AreEqual(minimum, maximum))
{
thumbCenterPosition = 0;
}
_thumb.X = padding.X + thumbCenterPosition;
}
else
{
float contentHeight = ActualHeight - padding.Y - padding.W;
float thumbHeight = contentHeight * ViewportSize;
if (thumbHeight < _thumb.MinHeight)
{
thumbHeight = _thumb.MinHeight;
}
else if (thumbHeight > _thumb.MaxHeight)
{
thumbHeight = _thumb.MaxHeight;
}
_thumb.Height = thumbHeight;
_thumb.Measure(new Vector2F(float.PositiveInfinity));
contentHeight = ActualHeight - padding.Y - padding.W - thumbHeight;
float thumbCenterPosition = contentHeight / range * (value - Minimum);
if (Numeric.AreEqual(minimum, maximum))
{
thumbCenterPosition = 0;
}
_thumb.Y = padding.Y + thumbCenterPosition;
}
}
base.OnArrange(position, size);
}
