/// <summary>
/// Creates the list of candidates where the edge creation ends.
/// </summary>
private IEnumerable <IPortCandidate> GenerateEndNodePortCandidates(IInputModeContext context)
{
var canvasControl = context.CanvasControl;
// check if behavior is toggled.
var shiftPressed = KeyEventRecognizers.ShiftPressed(context.CanvasControl, canvasControl.LastInputEvent);
// check if the node is already occupied in that direction
var targetNodeOccupied = IsTargetNodeOccupied(context, node);
if (shiftPressed != targetNodeOccupied)
{
// only display dynamic port candidates
return(new IPortCandidate[] {
new DefaultPortCandidate(node, FreeNodePortLocationModel.Instance),
});
}
else
{
// only display static port candidates
var existingPorts = new List <IPortCandidate>();
AddExistingPorts(node, existingPorts);
if (node.Lookup <ITable>() == null)
{
// don't provide a default port for table nodes
existingPorts.Add(new DefaultPortCandidate(node, FreeNodePortLocationModel.NodeCenterAnchored));
}
return(existingPorts);
}
}
/// <summary>
/// Returns <see cref="HandlePositions.Corners"/> or <see cref="HandlePositions.Border"/> as available handle
/// positions depending on the modifier state of <c>Ctrl</c>.
/// </summary>
/// <param name="context">The context the handles are created in.</param>
/// <returns><see cref="HandlePositions.Corners"/> or <see cref="HandlePositions.Border"/></returns>
public HandlePositions GetAvailableHandles(IInputModeContext context)
{
var ctrlPressed = KeyEventRecognizers.CtrlPressed(this, context.CanvasControl.LastMouse2DEvent);
// when Ctrl is pressed, all border positions are returned, otherwise only the corner positions
return(ctrlPressed ? HandlePositions.Border : HandlePositions.Corners);
}
protected override IEnumerable <IPortCandidate> GetPortCandidates(IInputModeContext context)
{
var portCandidates = new List <IPortCandidate>();
// provide existing ports as candidates only if they use EventPortStyle and have no edges attached to them.
foreach (IPort port in node.Ports)
{
if (port.Style is EventPortStyle && context.Lookup <IGraph>().EdgesAt(port).Count == 0)
{
portCandidates.Add(new DefaultPortCandidate(port));
}
}
if (node.Style is ActivityNodeStyle || node.Style is ChoreographyNodeStyle ||
node.Style is DataObjectNodeStyle || node.Style is AnnotationNodeStyle ||
node.Style is GroupNodeStyle || node.Style is DataStoreNodeStyle)
{
portCandidates.Add(new DefaultPortCandidate(node, FreeNodePortLocationModel.NodeTopAnchored));
portCandidates.Add(new DefaultPortCandidate(node, FreeNodePortLocationModel.NodeBottomAnchored));
portCandidates.Add(new DefaultPortCandidate(node, FreeNodePortLocationModel.NodeLeftAnchored));
portCandidates.Add(new DefaultPortCandidate(node, FreeNodePortLocationModel.NodeRightAnchored));
}
else if (node.Style is EventNodeStyle || node.Style is GatewayNodeStyle)
{
double dmax = Math.Min(node.Layout.Width / 2, node.Layout.Height / 2);
var model = FreeNodePortLocationModel.Instance;
portCandidates.Add(new DefaultPortCandidate(node, model.CreateParameter(new PointD(0.5, 0.5), new PointD(0, -dmax))));
portCandidates.Add(new DefaultPortCandidate(node, model.CreateParameter(new PointD(0.5, 0.5), new PointD(dmax, 0))));
portCandidates.Add(new DefaultPortCandidate(node, model.CreateParameter(new PointD(0.5, 0.5), new PointD(0, dmax))));
portCandidates.Add(new DefaultPortCandidate(node, model.CreateParameter(new PointD(0.5, 0.5), new PointD(-dmax, 0))));
}
else if (node.Style is ConversationNodeStyle)
{
double dx = 0.5 * Math.Min(node.Layout.Width, node.Layout.Height / BpmnConstants.ConversationWidthHeightRatio);
double dy = dx * BpmnConstants.ConversationWidthHeightRatio;
var model = FreeNodePortLocationModel.Instance;
portCandidates.Add(new DefaultPortCandidate(node, model.CreateParameter(new PointD(0.5, 0.5), new PointD(0, -dy))));
portCandidates.Add(new DefaultPortCandidate(node, model.CreateParameter(new PointD(0.5, 0.5), new PointD(dx, 0))));
portCandidates.Add(new DefaultPortCandidate(node, model.CreateParameter(new PointD(0.5, 0.5), new PointD(0, dy))));
portCandidates.Add(new DefaultPortCandidate(node, model.CreateParameter(new PointD(0.5, 0.5), new PointD(-dx, 0))));
}
var ceim = context.ParentInputMode as CreateEdgeInputMode;
var canvasControl = context.CanvasControl;
if (ceim == null || canvasControl == null || KeyEventRecognizers.ShiftPressed(canvasControl, canvasControl.LastMouse2DEvent))
{
// add a dynamic candidate
portCandidates.Add(new DefaultPortCandidate(node, new FreeNodePortLocationModel()));
}
return(portCandidates);
}
/// <summary>
/// A custom <see cref="EventRecognizer"/> to be used as modifier recognizer.
/// </summary>
/// <remarks>
/// Has to return true if the move input mode is allowed to move a node.
/// </remarks>
private bool IsRecognized(object eventSource, EventArgs eventArg)
{
// return the value according to the Mode combo box
switch (cmbMode.SelectedIndex)
{
case 0: // always
case 2: // on top (this is handled by custom IHitTestable)
// the same as the unmodified MoveUnselectedInputMode;
return(true);
case 1: // shift is not pressed
return(!KeyEventRecognizers.ShiftPressed(eventSource, eventArg));
case 3: // if enabled
return(btnEnable.Checked);
default:
return(false);
}
}
/// <summary>
/// Creates the list of candidates where the edge creation starts.
/// </summary>
private IEnumerable <IPortCandidate> GenerateStartNodePortCandidates(IInputModeContext context)
{
var canvasControl = context.CanvasControl;
// since we turned on dynamic port candidate resolution without a modifier in the demo, we decide here
// what to do.
if (KeyEventRecognizers.ShiftPressed(context.CanvasControl, canvasControl.LastInputEvent))
{
// yield the center and a dynamic candidate
return(new IPortCandidate[] {
new DefaultPortCandidate(node, FreeNodePortLocationModel.NodeCenterAnchored),
new DefaultPortCandidate(node, FreeNodePortLocationModel.Instance),
});
}
else
{
// yield static candidates, only
var existingPorts = new List <IPortCandidate>();
AddExistingPorts(node, existingPorts);
existingPorts.Add(new DefaultPortCandidate(node, FreeNodePortLocationModel.NodeCenterAnchored));
return(existingPorts);
}
}
