TemporaryConnection class

Represents a temporary connection during a drag-and-drop operation.

A TemporaryConnection is created when a user starts dragging from a port and is updated as the mouse/pointer moves. It becomes a permanent connection when dropped on a valid target port, or is discarded if the drag is cancelled.

Port Direction Semantics

The isStartFromOutput flag determines the logical role of each endpoint:

When true (dragging from output): start port is SOURCE, mouse is TARGET
When false (dragging from input): start port is TARGET, mouse is SOURCE

This is important for path routing - connections always flow from source to target.

Immutable Properties (Set at Start)

startPoint: Where the drag started (port position)
startNodeId: ID of the node where drag started
startPortId: ID of the port where drag started
isStartFromOutput: Whether the drag started from an output port
startNodeBounds: Bounds of the starting node (for routing)

Observable Properties (Change During Drag)

currentPoint: Current pointer position
targetNodeId: ID of the hovered node (null until hovering over valid target)
targetPortId: ID of the hovered port (null until hovering over valid target)
targetNodeBounds: Bounds of the hovered node (null until hovering)

Usage Example

// Create when drag starts from an output port
final tempConnection = TemporaryConnection(
  startPoint: portPosition,
  startNodeId: 'node-1',
  startPortId: 'port-out',
  isStartFromOutput: true,
  startNodeBounds: node.getBounds(),
  initialCurrentPoint: portPosition,
);

// Update as pointer moves
tempConnection.currentPoint = newPointerPosition;

// Set target when hovering over a valid port
tempConnection.targetNodeId = 'node-2';
tempConnection.targetPortId = 'port-in';
tempConnection.targetNodeBounds = targetNode.getBounds();

Constructors

TemporaryConnection({required Offset startPoint, required String startNodeId, required String startPortId, required bool isStartFromOutput, required Rect startNodeBounds, required Offset initialCurrentPoint, String? targetNodeId, String? targetPortId, Rect? targetNodeBounds}): Creates a temporary connection for drag-and-drop operations.

Properties

currentPoint ↔ Offset: The current pointer position.
getter/setter pair
currentPointObservable → Observable<Offset>: Gets the MobX observable for the current point.
no setter
hashCode → int: The hash code for this object.
no setteroverride
isStartFromOutput → bool: Whether the drag started from an output port.
final
runtimeType → Type: A representation of the runtime type of the object.
no setterinherited
startNodeBounds → Rect: Bounds of the node where the drag started.
final
startNodeId → String: ID of the node where the drag started.
final
startPoint → Offset: The position where the drag started (port position).
final
startPortId → String: ID of the port where the drag started.
final
targetNodeBounds ↔ Rect?: Bounds of the hovered node.
getter/setter pair
targetNodeBoundsObservable → Observable<Rect?>: Gets the MobX observable for the target node bounds.
no setter
targetNodeId ↔ String?: ID of the hovered node.
getter/setter pair
targetNodeIdObservable → Observable<String?>: Gets the MobX observable for the target node ID.
no setter
targetPortId ↔ String?: ID of the hovered port.
getter/setter pair
targetPortIdObservable → Observable<String?>: Gets the MobX observable for the target port ID.
no setter

Methods

noSuchMethod(Invocation invocation) → dynamic: Invoked when a nonexistent method or property is accessed.
inherited
toString() → String: A string representation of this object.
inherited

Operators

operator ==(Object other) → bool: The equality operator.
override