/// <summary>
/// Called as the user continues to drag the connection.
/// </summary>
public void ConnectionDragging(Point curDragPoint, AConnectionViewModel connection)
{
if (connection.DestConnector == null)
{
connection.DestConnectorHotspot = curDragPoint;
}
else
{
connection.SourceConnectorHotspot = curDragPoint;
}
}
/// <summary>
/// Utility method to delete a connection from the view-model.
/// </summary>
public void DeleteConnection(AConnectionViewModel connection)
{
this.Network.Connections.Remove(connection);
}
/// <summary>
/// Called when the user has finished dragging out the new connection.
/// Only one left- right connection is allowed
/// invalid connections are removed
/// </summary>
///
public void ConnectionDragCompleted(AConnectionViewModel newConnection, ConnectorViewModel connectorDraggedOut, ConnectorViewModel connectorDraggedOver)
{
if (connectorDraggedOver == null)
{
//
// The connection was unsuccessful.
// Maybe the user dragged it out and dropped it in empty space.
//
Network.Connections.Remove(newConnection);
return;
}
var validPathConnection = IsValidPathConnection(connectorDraggedOut, connectorDraggedOver);
bool connectionOk = validPathConnection ||
IsValidInputOutputConnection(connectorDraggedOut, connectorDraggedOver);
if (!connectionOk)
{
Network.Connections.Remove(newConnection);
return;
}
if (validPathConnection)
{
var isConnectingFromLeftToRight = connectorDraggedOut.Name == NodeViewModel.DefaultRightNodeConnectorName;
var sourceConnector = isConnectingFromLeftToRight ? connectorDraggedOut : connectorDraggedOver;
var destConnector = isConnectingFromLeftToRight ? connectorDraggedOver : connectorDraggedOut;
var sourceRightConnection = sourceConnector.ParentNode.RightNodeConnection;
var destinationLeftConnection = destConnector.ParentNode.LeftNodeConnection;
if (sourceRightConnection != null && sourceRightConnection.IsConnected)
{
var existingConnection = sourceRightConnection.AttachedConnections.Single(c => c.DestConnector != null);
Network.Connections.Remove(existingConnection);
}
if (destinationLeftConnection != null && destinationLeftConnection.IsConnected)
{
var existingConnection = destinationLeftConnection.AttachedConnections.Single(c => c.SourceConnector != null);
Network.Connections.Remove(existingConnection);
}
}
else
{
//
// Remove any existing connection between the same two connectors.
//
var existingConnection = FindConnection(connectorDraggedOut, connectorDraggedOver);
if (existingConnection != null)
{
Network.Connections.Remove(existingConnection);
}
}
//
// Finalize the connection by attaching it to the connector
// that the user dragged the mouse over.
//
if (newConnection.DestConnector == null)
{
newConnection.DestConnector = connectorDraggedOver;
}
else
{
newConnection.SourceConnector = connectorDraggedOver;
}
}
