/// <summary>
/// Reconfigure components that enter and leave.
/// </summary>
/// <param name="sender"></param>
/// <param name="nccea"></param>
void Components_CollectionChanged(object sender, NotifyCollectionChangedEventArgs nccea)
{
var celc = new DefaultEnterLeaveContext(Surface, Components, Layers, DataContext);
try {
if (nccea.OldItems != null)
{
foreach (ChartComponent cc in nccea.OldItems)
{
_trace.Verbose($"leave '{cc.Name}' {cc}");
cc.RefreshRequest -= ChartComponent_RefreshRequest;
ComponentLeave(celc, cc);
}
}
if (nccea.NewItems != null)
{
foreach (ChartComponent cc in nccea.NewItems)
{
_trace.Verbose($"enter '{cc.Name}' {cc}");
cc.RefreshRequest -= ChartComponent_RefreshRequest;
cc.RefreshRequest += ChartComponent_RefreshRequest;
cc.DataContext = DataContext;
if (Surface != null)
{
ComponentEnter(celc, cc);
}
else
{
DeferredEnter.Add(cc);
}
}
}
}
catch (Exception ex) {
_trace.Error($"{Name} Components_CollectionChanged.unhandled: {ex}");
}
if (celc.Errors.Count > 0)
{
Report(celc.Errors.ToArray());
}
if (Surface != null)
{
InvalidateArrange();
}
}
/// <summary>
/// Obtain UI elements from the control template.
/// Happens Before Chart_LayoutUpdated.
/// </summary>
protected override void OnApplyTemplate()
{
try {
Surface = GetTemplateChild(PART_Canvas) as Canvas;
_trace.Verbose($"OnApplyTemplate ({Width}x{Height}) {Surface} d:{DeferredEnter.Count} composition:{UniversalApiContract.v3.CompositionSupport.IsSupported}");
var celc = new DefaultEnterLeaveContext(Surface, Components, Layers, DataContext);
foreach (var cc in DeferredEnter)
{
ComponentEnter(celc, cc);
}
DeferredEnter.Clear();
if (celc.Errors.Count > 0)
{
Report(celc.Errors.ToArray());
}
} finally {
base.OnApplyTemplate();
}
}
