Class: QgsModelGraphicsScene¶

QGraphicsScene subclass representing the model designer.

Warning

Not stable API

Added in version 3.14.

Class Hierarchy¶

Base classes¶

QGraphicsScene
QObject

Methods

`componentItemAt`	Returns the topmost component item at a specified position.
`createChildAlgGraphicItem`	Creates a new graphic item for a model child algorithm.
`createCommentGraphicItem`	Creates a new graphic item for a model comment.
`createGroupBoxGraphicItem`	Creates a new graphic item for a model group box.
`createItems`	Populates the scene by creating items representing the specified model.
`createOutputGraphicItem`	Creates a new graphic item for a model output.
`createParameterGraphicItem`	Creates a new graphic item for a model parameter.
`deselectAll`	Clears any selected items in the scene.
`flags`	Returns the current combination of flags set for the scene.
`groupBoxItem`	Returns the graphic item corresponding to the specified group box uuid.
`messageBar`	Returns the message bar associated with the scene.
`model`
`selectAll`	Selects all the components in the scene.
`selectedComponentItems`	Returns list of selected component items.
`setFlag`	Enables or disables a particular flag for the scene.
`setFlags`	Sets the combination of flags controlling how the scene is rendered and behaves.
`setLastRunResult`	Sets the result of the last run of the model through the designer window.
`setMessageBar`	Sets the message bar associated with the scene.
`setModel`
`setSelectedItem`	Clears any selected items and sets item as the current selection.
`showWarning`	Shows a warning message, allowing users to click a button to see the full details (longMessage).

Signals

`componentAboutToChange`	Emitted whenever a component of the model is about to be changed.
`componentChanged`	Emitted whenever a component of the model is changed.
`rebuildRequired`	Emitted when a change in the model requires a full rebuild of the scene.
`runFromChild`	Emitted when the user opts to run the part of the model starting from the specified child algorithm.
`runSelected`	Emitted when the user opts to run selected steps from the model.
`selectedItemChanged`	Emitted whenever the selected item changes.
`showChildAlgorithmLog`	Emitted when the user opts to view the previous log from the child algorithm with matching ID.
`showChildAlgorithmOutputs`	Emitted when the user opts to view previous results from the child algorithm with matching ID.

Attributes

`ArrowLink`
`FlagHideComments`
`FlagHideControls`
`GroupBox`
`ModelComponent`
`MouseHandles`
`RubberBand`
`ZSnapIndicator`

class qgis.gui.QgsModelGraphicsScene[source]¶

Bases: QGraphicsScene

__init__(parent: QObject | None = None)

Constructor for QgsModelGraphicsScene with the specified parent object.

Parameters:: parent (Optional[QObject] = None)

ArrowLink = 1¶

class Flag¶: Bases: int

FlagHideComments = 4¶

FlagHideControls = 2¶

class Flags¶
class Flags(f: QgsModelGraphicsScene.Flags | QgsModelGraphicsScene.Flag)
class Flags(a0: QgsModelGraphicsScene.Flags): Bases: object

GroupBox = 0¶

ModelComponent = 2¶

MouseHandles = 99¶

RubberBand = 100¶

ZSnapIndicator = 101¶

class ZValues¶: Bases: int

signal componentAboutToChange(text: str, id: int = 0)[source]¶

Emitted whenever a component of the model is about to be changed.

The text argument gives the translated text describing the change about to occur, and the optional id can be used to group the associated undo commands.

Parameters:

text (str)
id (int = 0)

signal componentChanged[source]¶: Emitted whenever a component of the model is changed.

componentItemAt(self, position: QPointF | QPoint) → QgsModelComponentGraphicItem | None[source]¶

Returns the topmost component item at a specified position.

Parameters:: position (Union[QPointF, QPoint])
Return type:: Optional[QgsModelComponentGraphicItem]

createChildAlgGraphicItem(self, model: QgsProcessingModelAlgorithm | None, child: QgsProcessingModelChildAlgorithm | None) → QgsModelChildAlgorithmGraphicItem | None[source]¶

Creates a new graphic item for a model child algorithm.

Parameters:

model (Optional[QgsProcessingModelAlgorithm])
child (Optional[QgsProcessingModelChildAlgorithm])

Return type:

Optional[QgsModelChildAlgorithmGraphicItem]

createCommentGraphicItem(self, model: QgsProcessingModelAlgorithm | None, comment: QgsProcessingModelComment | None, parentItem: QgsModelComponentGraphicItem | None) → QgsModelComponentGraphicItem | None[source]¶

Creates a new graphic item for a model comment.

Parameters:

model (Optional[QgsProcessingModelAlgorithm])
comment (Optional[QgsProcessingModelComment])
parentItem (Optional[QgsModelComponentGraphicItem])

Return type:

Optional[QgsModelComponentGraphicItem]

createGroupBoxGraphicItem(self, model: QgsProcessingModelAlgorithm | None, box: QgsProcessingModelGroupBox | None) → QgsModelComponentGraphicItem | None[source]¶

Creates a new graphic item for a model group box.

Parameters:

model (Optional[QgsProcessingModelAlgorithm])
box (Optional[QgsProcessingModelGroupBox])

Return type:

Optional[QgsModelComponentGraphicItem]

createItems(self, model: QgsProcessingModelAlgorithm | None, context: QgsProcessingContext)[source]¶

Populates the scene by creating items representing the specified model.

Parameters:

model (Optional[QgsProcessingModelAlgorithm])
context (QgsProcessingContext)

createOutputGraphicItem(self, model: QgsProcessingModelAlgorithm | None, output: QgsProcessingModelOutput | None) → QgsModelComponentGraphicItem | None[source]¶

Creates a new graphic item for a model output.

Parameters:

model (Optional[QgsProcessingModelAlgorithm])
output (Optional[QgsProcessingModelOutput])

Return type:

Optional[QgsModelComponentGraphicItem]

createParameterGraphicItem(self, model: QgsProcessingModelAlgorithm | None, param: QgsProcessingModelParameter | None) → QgsModelComponentGraphicItem | None[source]¶

Creates a new graphic item for a model parameter.

Parameters:

model (Optional[QgsProcessingModelAlgorithm])
param (Optional[QgsProcessingModelParameter])

Return type:

Optional[QgsModelComponentGraphicItem]

deselectAll(self)[source]¶

Clears any selected items in the scene.

Call this method rather than QGraphicsScene.clearSelection, as the latter does not correctly emit signals to allow the scene’s model to update.

flags(self) → QgsModelGraphicsScene.Flags[source]¶

Returns the current combination of flags set for the scene.

See also

setFlags()

See also

setFlag()

Return type:: QgsModelGraphicsScene.Flags

groupBoxItem(self, uuid: str | None) → QgsModelComponentGraphicItem | None[source]¶

Returns the graphic item corresponding to the specified group box uuid.

Parameters:: uuid (Optional[str])
Return type:: Optional[QgsModelComponentGraphicItem]

messageBar(self) → QgsMessageBar | None[source]¶

Returns the message bar associated with the scene.

See also

setMessageBar()

Return type:: Optional[QgsMessageBar]

model(self) → QgsProcessingModelAlgorithm | None[source]¶

Return type:: Optional[QgsProcessingModelAlgorithm]

signal rebuildRequired[source]¶: Emitted when a change in the model requires a full rebuild of the scene.

signal runFromChild(childId: str)[source]¶

Emitted when the user opts to run the part of the model starting from the specified child algorithm.

Added in version 3.38.

Parameters:: childId (str)

signal runSelected[source]¶: Emitted when the user opts to run selected steps from the model.

Added in version 3.38.

selectAll(self)[source]¶: Selects all the components in the scene.

selectedComponentItems(self) → List[QgsModelComponentGraphicItem]¶

Returns list of selected component items.

Return type:: List[QgsModelComponentGraphicItem]

signal selectedItemChanged(selected: QgsModelComponentGraphicItem)[source]¶

Emitted whenever the selected item changes. If None, no item is selected.

Parameters:: selected (QgsModelComponentGraphicItem)

setFlag(self, flag: QgsModelGraphicsScene.Flag, on: bool = True)[source]¶

Enables or disables a particular flag for the scene. Other existing flags are not affected.

See also

setFlags()

See also

flags()

Parameters:

flag (QgsModelGraphicsScene.Flag)
on (bool = True)

setFlags(self, flags: QgsModelGraphicsScene.Flags | QgsModelGraphicsScene.Flag)[source]¶

Sets the combination of flags controlling how the scene is rendered and behaves.

See also

setFlag()

See also

flags()

Parameters:: flags (Union[QgsModelGraphicsScene.Flags, QgsModelGraphicsScene.Flag])

setLastRunResult(self, result: QgsProcessingModelResult)[source]¶

Sets the result of the last run of the model through the designer window.

Parameters:: result (QgsProcessingModelResult)

setMessageBar(self, bar: QgsMessageBar | None)[source]¶

Sets the message bar associated with the scene.

See also

messageBar()

Parameters:: bar (Optional[QgsMessageBar])

setModel(self, model: QgsProcessingModelAlgorithm | None)[source]¶

Parameters:: model (Optional[QgsProcessingModelAlgorithm])

setSelectedItem(self, item: QgsModelComponentGraphicItem | None)[source]¶

Clears any selected items and sets item as the current selection.

Parameters:: item (Optional[QgsModelComponentGraphicItem])

signal showChildAlgorithmLog(childId: str)[source]¶

Emitted when the user opts to view the previous log from the child algorithm with matching ID.

Added in version 3.38.

Parameters:: childId (str)

signal showChildAlgorithmOutputs(childId: str)[source]¶

Emitted when the user opts to view previous results from the child algorithm with matching ID.

Added in version 3.38.

Parameters:: childId (str)

showWarning(self, shortMessage: str | None, title: str | None, longMessage: str | None, level: Qgis.MessageLevel = Qgis.MessageLevel.Warning)[source]¶

Shows a warning message, allowing users to click a button to see the full details (longMessage).

Parameters:

shortMessage (Optional[str])
title (Optional[str])
longMessage (Optional[str])
level (Qgis.MessageLevel = Qgis.MessageLevel.Warning)