Canvas Scene (scene)¶

class orangecanvas.canvas.scene.CanvasScene(*args, **kwargs)¶

Bases: PyQt5.QtWidgets.QGraphicsScene

A Graphics Scene for displaying an Scheme instance.

node_item_added(NodeItem)¶

Signal emitted when a NodeItem has been added to the scene.

node_item_removed(NodeItem)¶

Signal emitted when a NodeItem has been removed from the scene.

link_item_added(LinkItem)¶

Signal emitted when a new LinkItem has been added to the scene.

link_item_removed(LinkItem)¶

Signal emitted when a LinkItem has been removed.

annotation_added(Annotation)¶

Signal emitted when a Annotation item has been added.

annotation_removed(Annotation)¶

Signal emitted when a Annotation item has been removed.

node_item_position_changed(NodeItem, QPointF)¶

Signal emitted when the position of a NodeItem has changed.

node_item_double_clicked(NodeItem)¶

Signal emitted when an NodeItem has been double clicked.

node_item_activated(NodeItem)¶

An node item has been activated (clicked)

node_item_hovered(NodeItem)¶

An node item has been hovered

link_item_hovered(LinkItem)¶

Link item has been hovered

clear_scene()¶

Clear (reset) the scene.

set_scheme(scheme)¶

Set the scheme to display. Populates the scene with nodes and links already in the scheme. Any further change to the scheme will be reflected in the scene.

Parameters:	scheme (Scheme) –

set_registry(registry)¶

Set the widget registry.

set_anchor_layout(layout)¶

Set an AnchorLayout

anchor_layout()¶

Return the anchor layout instance.

set_channel_names_visible(visible)¶

Set the channel names visibility.

channel_names_visible()¶

Return the channel names visibility state.

set_node_animation_enabled(enabled)¶

Set node animation enabled state.

add_node_item(item)¶

Add a NodeItem instance to the scene.

add_node(node)¶

Add and return a default constructed NodeItem for a SchemeNode instance node. If the node is already in the scene do nothing and just return its item.

new_node_item(widget_desc, category_desc=None)¶

Construct an new NodeItem from a WidgetDescription. Optionally also set CategoryDescription.

remove_node_item(item)¶

Remove item (NodeItem) from the scene.

remove_node(node)¶

Remove the NodeItem instance that was previously constructed for a SchemeNode node using the add_node method.

node_items()¶

Return all NodeItem instances in the scene.

add_link_item(item)¶

Add a link (LinkItem) to the scene.

add_link(scheme_link)¶

Create and add a LinkItem instance for a SchemeLink instance. If the link is already in the scene do nothing and just return its LinkItem.

new_link_item(source_item, source_channel, sink_item, sink_channel)¶

Construct and return a new LinkItem

remove_link_item(item)¶

Remove a link (LinkItem) from the scene.

remove_link(scheme_link)¶

Remove a LinkItem instance that was previously constructed for a SchemeLink instance link using the add_link method.

link_items()¶

Return all LinkItems in the scene.

add_annotation_item(annotation)¶

Add an Annotation item to the scene.

add_annotation(scheme_annot)¶

Create a new item for SchemeAnnotation and add it to the scene. If the scheme_annot is already in the scene do nothing and just return its item.

remove_annotation_item(annotation)¶

Remove an Annotation instance from the scene.

remove_annotation(scheme_annotation)¶

Remove an Annotation instance that was previously added using add_anotation().

annotation_items()¶

Return all Annotation items in the scene.

commit_scheme_node(node)¶

Commit the node into the scheme.

commit_scheme_link(link)¶

Commit a scheme link.

node_for_item(item)¶

Return the SchemeNode for the item.

item_for_node(node)¶

Return the NodeItem instance for a SchemeNode.

link_for_item(item)¶

Return the SchemeLink for `item (LinkItem).

item_for_link(link)¶

Return the LinkItem for a SchemeLink

selected_node_items()¶

Return the selected NodeItem‘s.

selected_annotation_items()¶

Return the selected Annotation‘s

node_links(node_item)¶

Return all links from the node_item (NodeItem).

node_output_links(node_item)¶

Return a list of all output links from node_item.

node_input_links(node_item)¶

Return a list of all input links for node_item.

neighbor_nodes(node_item)¶

Return a list of node_item‘s (class:NodeItem) neighbor nodes.

item_at(pos, type_or_tuple=None, buttons=0)¶

Return the item at pos that is an instance of the specified type (type_or_tuple). If buttons (Qt.MouseButtons) is given only return the item if it is the top level item that would accept any of the buttons (QGraphicsItem.acceptedMouseButtons).

orangecanvas.canvas.scene.grab_svg(scene)¶

Return a SVG rendering of the scene contents.

Parameters:	scene (CanvasScene) –