private static ChartPanelHitTestResult HandleChartPanelHit(ChartPanel chartPanel, UIElement element, Point point)
{
return new ChartPanelHitTestResult
{
ChartPanel = chartPanel,
Visual = element,
Position = point,
};
}
private static void OnYAxisChanged(DependencyObject dependencyObject, DependencyPropertyChangedEventArgs eventArgs)
{
if (eventArgs.OldValue == eventArgs.NewValue)
return;
// Synchronize the attached dependency property ChartPanel.YAxis with the dependency
// property ChartElement.YAxis.
Axis yAxis = (Axis)eventArgs.NewValue;
ChartPanel.SetYAxis(dependencyObject, yAxis);
// Call ChartElement.OnYAxisChanged to raise the Invalidated event.
((ChartElement)dependencyObject).OnYAxisChanged(eventArgs);
}
/// <summary>
/// Raises the <see cref="ChartElement.Updated"/> event.
/// </summary>
/// <remarks>
/// <strong>Notes to Inheritors:</strong> When overriding <see cref="OnUpdate"/> in a
/// derived class, be sure to call the base class's <see cref="OnUpdate"/> method so that
/// registered delegates receive the event.
/// </remarks>
protected override void OnUpdate()
{
if (_background != null)
{
Rect bounds = ChartPanel.GetChartAreaBounds(XAxis, YAxis);
_background.Margin = new Thickness(bounds.Left, bounds.Top, 0, 0);
_background.Width = bounds.Width;
_background.Height = bounds.Height;
_background.HorizontalAlignment = HorizontalAlignment.Left;
_background.VerticalAlignment = VerticalAlignment.Top;
_background.Visibility = Visibility.Visible;
}
base.OnUpdate();
}
protected FrameworkElement CreateDataPoint(object dataContext)
{
if (DataPointTemplate == null)
throw new ChartException("Cannot create data point. DataPointTemplate is not set.");
var marker = DataPointTemplate.LoadContent() as FrameworkElement;
if (marker != null)
{
if (dataContext != null)
marker.DataContext = dataContext;
ChartPanel.SetIsDataPoint(marker, true);
marker.SetBinding(StyleProperty, new Binding("DataPointStyle") { Source = this });
}
return marker;
}
/// <summary>
/// Raises the <see cref="ChartElement.Updated"/> event.
/// </summary>
/// <remarks>
/// <strong>Notes to Inheritors:</strong> When overriding <see cref="OnUpdate"/> in a
/// derived class, be sure to call the base class's <see cref="OnUpdate"/> method so that
/// the base class <see cref="Chart"/> can update the data source if required.
/// </remarks>
protected override void OnUpdate()
{
base.OnUpdate(); // Updates the data source, if required.
// Cleanup
_lineRenderer.Clear();
_areaRenderer.Clear();
Debug.Assert(Canvas.Children.Count == 0, "Canvas should be cleared in base class.");
Canvas.Children.Add(_areaPath);
Canvas.Children.Add(_linePath);
if (Data != null && Data.Count != 0)
{
// Clip filled area and lines to the chart area.
Rect chartArea = ChartPanel.GetChartAreaBounds(XAxis, YAxis);
// Allow line to draw on chart axes.
Rect lineClipRect = new Rect(chartArea.Left - 2, chartArea.Top - 2, chartArea.Width + 4, chartArea.Height + 4);
LineClipGeometry = new RectangleGeometry { Rect = lineClipRect };
// Keep area inside the chart area.
Rect areaClipRect = chartArea;
AreaClipGeometry = new RectangleGeometry { Rect = areaClipRect };
FindVisibleDataPoints();
CachePositions();
OnUpdateLines(_startIndex, _endIndexExclusive, _xPositions, _basePositions, _yPositions);
UpdateMarkers();
#else
switch (RenderMode)
{
case ChartRenderMode.Quality:
// Update lines and markers immediately.
OnUpdateLines(_startIndex, _endIndexExclusive, _xPositions, _basePositions, _yPositions);
UpdateMarkers();
break;
case ChartRenderMode.Performance:
// Immediately update lines.
OnUpdateLines(_startIndex, _endIndexExclusive, _xPositions, _basePositions, _yPositions);
// Temporarily disable bitmap cache and anti-aliasing.
// Update markers when application is idle.
if (!_updatePending)
{
_updatePending = true;
ClearCacheMode();
ClearEdgeMode();
ChartHelper.Defer(Dispatcher, () =>
{
if (_updatePending)
{
_updatePending = false;
UpdateMarkers();
RestoreCacheMode();
RestoreEdgeMode();
}
});
}
break;
case ChartRenderMode.DoNotRender:
// Do nothing.
break;
}
}
}
