Scheme Link (link)
Scheme Link
- class orangecanvas.scheme.link.SchemeLink(source_node: Node, source_channel: Output, sink_node: Node, sink_channel: Input, enabled: bool = True, properties: dict = None, parent: QObject = None)[source]
Bases:
PyQt5.QtCore.QObjectA instantiation of a link between two
SchemeNodeinstances in aScheme.- Parameters
source_node (
SchemeNode) – Source node.source_channel (
OutputSignal) – The source widget’s signal.sink_node (
SchemeNode) – The sink node.sink_channel (
InputSignal) – The sink widget’s input signal.properties (dict) – Additional link properties.
- enabled_changed(enabled)
The link enabled state has changed
- dynamic_enabled_changed(enabled)
The link dynamic enabled state has changed.
- state_changed
Runtime link state has changed
- class State(value)[source]
Bases:
enum.IntEnumFlags indicating the runtime state of a link
- NoState = 0
The link has no associated state (e.g. is not associated with any execution contex)
- Empty = 1
A link is empty when it has no value on it.
- Active = 2
A link is active when the source node provides a value on output.
- Pending = 4
A link is pending when it’s sink node has not yet been notified of a change (note that Empty|Pending is a valid state)
- Invalidated = 8
The link’s source node has invalidated the source channel. The execution manager should not propagate this links source value until this flag is cleared.
New in version 0.1.8.
- source_type() type[source]
Return the type of the source channel.
Deprecated since version 0.1.5: Use
source_types()instead.
- sink_type() type[source]
Return the type of the sink channel.
Deprecated since version 0.1.5: Use
sink_types()instead.
- set_dynamic_enabled(enabled: bool) None[source]
Enable/disable the dynamic link. Has no effect if the link is not dynamic.
- set_runtime_state(state: Union[State, int]) None[source]
Set the link’s runtime state.
- Parameters
state (SchemeLink.State) –
- set_runtime_state_flag(flag: State, on: bool) None[source]
Set/unset runtime state flag.
- Parameters
flag (SchemeLink.State) –
on (bool) –
- test_runtime_state(flag: State) bool[source]
Test if runtime state flag is on/off
- Parameters
flag (SchemeLink.State) – State flag to test
- Returns
on – True if flag is set; False otherwise.
- Return type