/// <summary>
/// Sets the <see cref="ColorStop.IsSelected"/> properties of the <see cref="ColorStop"/>
/// controls.
/// </summary>
/// <remarks>The selection is determined by _selectedIndex.</remarks>
private void SetSelection()
{
if (_colorStopPanel == null || GradientStops == null)
{
return;
}
foreach (var child in _colorStopPanel.Children)
{
ColorStop control = child as ColorStop;
if (control != null)
{
GradientStop gradientStop = (GradientStop)control.Tag;
control.IsSelected = (_selectedIndex == GradientStops.IndexOf(gradientStop));
}
}
}
/// <summary>
/// Updates the color stop controls in the ColorStopPanel.
/// </summary>
private void UpdateColorStops()
{
if (_colorStopPanel == null)
{
return;
}
// Remember the focused color stop.
var oldFocusedStopControl = _colorStopPanel.Children.OfType <ColorStop>().FirstOrDefault(cs => cs.IsFocused);
GradientStop oldFocusedStop = null;
if (oldFocusedStopControl != null)
{
oldFocusedStop = oldFocusedStopControl.Tag as GradientStop;
}
// Remove previous ColorStop controls.
RemoveColorStopControls();
if (GradientStops != null)
{
// Create new ColorStop controls.
foreach (GradientStop stop in GradientStops)
{
var colorStop = new ColorStop
{
Color = stop.Color,
Focusable = true,
Tag = stop
};
colorStop.SetBinding(
WidthProperty, new Binding("ColorStopSize.Width")
{
Source = this, Mode = BindingMode.OneWay
});
colorStop.SetBinding(
HeightProperty, new Binding("ColorStopSize.Height")
{
Source = this, Mode = BindingMode.OneWay
});
colorStop.SetBinding(
SnapsToDevicePixelsProperty, new Binding("SnapsToDevicePixels")
{
Source = this, Mode = BindingMode.OneWay
});
colorStop.GotFocus += OnColorStopGotFocus;
colorStop.MouseDown += OnColorStopMouseDown;
_colorStopPanel.Children.Add(colorStop);
// Restore focus.
if (oldFocusedStop != null)
{
if (stop.Color == oldFocusedStop.Color && stop.Offset == oldFocusedStop.Offset)
{
colorStop.Focus();
oldFocusedStop = null;
}
}
// Position control.
double x;
switch (colorStop.HorizontalAlignment)
{
case HorizontalAlignment.Left:
x = stop.Offset * ActualWidth;
break;
case HorizontalAlignment.Right:
x = stop.Offset * ActualWidth - colorStop.Width;
break;
default:
x = stop.Offset * ActualWidth - colorStop.Width / 2;
break;
}
Canvas.SetLeft(colorStop, x);
}
SetSelection();
}
}