protected override VisualGroup UpdateVisual(IRenderContext context, VisualGroup group, INode node)
{
if (group == null)
{
return(CreateVisual(context, node));
}
// update the node visualization
group.Children[0] = NodeStyle.Renderer.GetVisualCreator(node, NodeStyle).UpdateVisual(context, group.Children[0]);
// update the "visual" ports
int count = 1;
foreach (var portDescriptor in PortDescriptor.CreatePortDescriptors(FlowChartType))
{
if (portDescriptor.X != int.MaxValue)
{
var parameter = FreeNodePortLocationModel.Instance.CreateParameter(PointD.Origin, new PointD(portDescriptor.X, portDescriptor.Y));
var port = new SimplePort(node, parameter)
{
LookupImplementation = Lookups.Empty
};
// see if we have a visual to update...
if (count < group.Children.Count)
{
var oldPortVisual = group.Children[count];
group.Children[count] = PortStyle.Renderer.GetVisualCreator(port, PortStyle).UpdateVisual(context, oldPortVisual);
}
else
{
// no - add a new one
var portVisual = PortStyle.Renderer.GetVisualCreator(port, PortStyle).CreateVisual(context);
group.Children.Add(portVisual);
}
}
count++;
}
// see if the number of ports decreased
while (count < group.Children.Count)
{
// yes, remove the old visual
var index = group.Children.Count - 1;
group.Children.RemoveAt(index);
}
return(group);
}
/// <summary>
/// Actually creates the visual appearance of a node.
/// </summary>
/// <remarks>
/// This renders the node and the edges to the labels and adds the visuals to the <paramref name="container"/>.
/// All items are arranged as if the node was located at (0,0). <see cref="CreateVisual"/> and <see cref="UpdateVisual"/>
/// finally arrange the container so that the drawing is translated into the final position.
/// </remarks>
private void Render(IRenderContext context, INode node, VisualGroup container)
{
var innerVisual = NodeStyle.Renderer.GetVisualCreator(node, NodeStyle).CreateVisual(context);
container.Add(innerVisual);
// draw "visual" ports
foreach (var portDescriptor in PortDescriptor.CreatePortDescriptors(FlowChartType))
{
if (portDescriptor.X != int.MaxValue)
{
var parameter = FreeNodePortLocationModel.Instance.CreateParameter(PointD.Origin, new PointD(portDescriptor.X, portDescriptor.Y));
var port = new SimplePort(node, parameter)
{
LookupImplementation = Lookups.Empty
};
var portVisual = PortStyle.Renderer.GetVisualCreator(port, PortStyle).CreateVisual(context);
container.Children.Add(portVisual);
}
}
}
/// <summary>
/// Perform the layout operation
/// </summary>
private async Task ApplyLayout()
{
// layout starting, disable button
layoutButton.IsEnabled = false;
// create the layout algorithm
var layout = new HierarchicLayout
{
OrthogonalRouting = true,
LayoutOrientation = LayoutOrientation.TopToBottom
};
// do the layout
await graphControl.MorphLayout(layout,
TimeSpan.FromSeconds(1),
new HierarchicLayoutData {
//Automatically determine port constraints for source and target
NodePortCandidateSets =
{
Delegate = node => {
var candidateSet = new PortCandidateSet();
// iterate the port descriptors
var descriptors = PortDescriptor.CreatePortDescriptors(((FlowChartNodeStyle)node.Style).FlowChartType);
foreach (var portDescriptor in descriptors)
{
PortCandidate candidate;
// isn't a fixed port candidate (location is variable)
if (portDescriptor.X == int.MaxValue)
{
// create a port candidate at the specified side (east, west, north, south) and apply a cost to it
candidate = PortCandidate.CreateCandidate(portDescriptor.Side, portDescriptor.Cost);
}
else
{
// create a candidate at a fixed location and side
var x = portDescriptor.X - node.Layout.Width / 2;
var y = portDescriptor.Y - node.Layout.Height / 2;
candidate = PortCandidate.CreateCandidate(x, y, portDescriptor.Side, portDescriptor.Cost);
}
candidateSet.Add(candidate, portDescriptor.Capacity);
}
return(candidateSet);
}
},
SourceGroupIds = { Delegate = edge => {
// create bus-like edge groups for outgoing edges at Start nodes
var sourceNode = edge.SourcePort.Owner as INode;
if (sourceNode != null && ((((FlowChartNodeStyle)sourceNode.Style).FlowChartType)) == FlowChartType.Start)
{
return(sourceNode);
}
return(null);
} },
TargetGroupIds = { Delegate = edge => {
// create bus-like edge groups for incoming edges at Branch nodes
var targetNode = edge.TargetPort.Owner as INode;
if (targetNode != null && (((FlowChartNodeStyle)targetNode.Style).FlowChartType) == FlowChartType.Branch)
{
return(targetNode);
}
return(null);
} }
});
// enable button again
layoutButton.IsEnabled = true;
}
