public GradientPointsControl()
{
SetStyle(ControlStyles.UserPaint, true);
SetStyle(ControlStyles.AllPaintingInWmPaint, true);
SetStyle(ControlStyles.ResizeRedraw, true);
SetStyle(ControlStyles.Opaque, true);
SetStyle(ControlStyles.Selectable, true);
SetStyle(ControlStyles.DoubleBuffer, true);
_gradientPoints = new GradientPointCollection(this);
ResetGradientPoints();
_startColor = c_DefStartColor;
_endColor = c_DefEndColor;
Padding = c_DefPadding;
_selectedPoint = _gradientPoints[0];
}
protected internal virtual void OnPointsChanged(
GradientPointCollection points)
{
if (_selectedPoint != null)
{
// update selected item
if (_gradientPoints.IndexOf(_selectedPoint) == -1)
{
if (_gradientPoints.Count == 0)
{
SelectedPoint = null;
}
else
{
int i;
for (i = 0; i < _gradientPoints.Count && _gradientPoints[i].Position < _selectedPoint.Position; i++)
{
;
}
if (i >= _gradientPoints.Count)
{
SelectedPoint = _gradientPoints[_gradientPoints.Count - 1];
}
else
{
SelectedPoint = _gradientPoints[i];
}
}
if (!UpdateLocked)
{
OnSelectedPointChanged();
}
}
}
if (!UpdateLocked)
{
Refresh();
}
}