Class: QgsModelComponentGraphicItem¶

Base class for graphic items representing model components in the model designer.

Warning

Not stable API

Added in version 3.14.

Note

This is an abstract class, with methods which must be implemented by a subclass.

The following methods must be implemented: fillColor(), strokeColor(), textColor(), updateStoredComponentPosition()

List of all members, including inherited members

Class Hierarchy¶

Base classes¶

QGraphicsObject
QObject
QGraphicsItem
`QgsProcessingWidgetContextGenerator`	An interface for objects which can create Processing widget contexts.

Subclasses¶

`QgsModelGroupBoxGraphicItem`	A graphic item representing a group box in the model designer.
`QgsModelOutputGraphicItem`	A graphic item representing a model output in the model designer.

Constructor

__init__

Enums

`Flag`
`State`

Abstract Methods

`fillColor`	Returns the fill color for the item for the specified state.
`strokeColor`	Returns the stroke color for the item for the specified state.
`textColor`	Returns the label text color for the item for the specified state.
`updateStoredComponentPosition`	Updates the position and size stored in the model for the associated comment

Methods

`Flags`
`calculateAutomaticLinkPoint`	Returns the best link point to use for a link originating at a specified other item.
`component`	Returns the model component associated with this item.
`font`	Returns the font used to render text in the item.
`incomingArrows`	Returns the list of incoming arrow items terminating at this item.
`itemRect`	Returns the rectangle representing the body of the item.
`label`	Returns the item's label text.
`linkPoint`	Returns the location of the link point with the specified index on the specified edge.
`model`	Returns the model associated with this item.
`moveComponentBy`	Moves the component by the specified dx and dy.
`outSocketAt`	Returns the output socket graphics items at the specified index.
`outgoingArrows`	Returns the list of outgoing arrow items originating at this item.
`paintOutline`	Paints the outline part of the graphic item.
`previewItemMove`	Shows a preview of moving the item from its stored position by dx, dy.
`registerWidgetContextGenerator`	Register a Processing widget context generator class that will be used to retrieve a widget context for the item when required.
`setFont`	Sets the font used to render text in the item.
`setItemRect`	Sets a new scene rect for the item.
`setLabel`	Returns the item's label text.
`state`	Returns the item's current state.
`truncatedTextForItem`	Truncates a text string so that it fits nicely within the item's width, accounting for margins and interactive buttons.
`updateButtonPositions`	Updates the item's button positions, based on the current item rect.
`view`	Returns the associated view.

Virtual Methods

In PyQGIS, only methods marked as virtual can be safely overridden in a Python subclass of QgsModelComponentGraphicItem. See the FAQ for more details.

`canDeleteComponent`	Returns `True` if the component can be deleted.
`deleteComponent`	Called when the component should be deleted.
`editComment`	Called when the comment attached to the item should be edited.
`editComponent`	Called when the component should be edited.
`flags`	Returns item flags.
`iconPicture`	Returns a QPicture version of the item's icon, if available.
`iconPixmap`	Returns a QPixmap version of the item's icon, if available.
`linkPointCount`	Returns the number of link points associated with the component on the specified edge.
`linkPointText`	Returns the text to use for the link point with the specified index on the specified edge.
`outlineColor`	Returns the optional color for an outline effect around the item.
`paintBackground`	Paints the background part of the graphic item.
`strokeStyle`	Returns the stroke style to use while rendering the outline of the item.
`titleAlignment`	Returns the title alignment

Signals

`aboutToChange`	Emitted when the definition of the associated component is about to be changed by the item.
`changed`	Emitted when the definition of the associated component is changed by the item.
`repaintArrows`	Emitted when item requests that all connected arrows are repainted.
`requestModelRepaint`	Emitted by the item to request a repaint of the parent model scene.
`sizePositionChanged`	Emitted when the item's size or position changes.
`updateArrowPaths`	Emitted when item requires that all connected arrow paths are recalculated.

class qgis.gui.QgsModelComponentGraphicItem¶

Bases: QGraphicsObject, QgsProcessingWidgetContextGenerator

__init__(component: QgsProcessingModelComponent | None, model: QgsProcessingModelAlgorithm | None, parent: QGraphicsItem | None)¶

Constructor for QgsModelComponentGraphicItem for the specified component, with the specified parent item.

The model argument specifies the associated processing model. Ownership of model is not transferred, and it must exist for the lifetime of this object.

Ownership of component is transferred to the item.

Parameters:

component (Optional[QgsProcessingModelComponent])
model (Optional[QgsProcessingModelAlgorithm])
parent (Optional[QGraphicsItem])

class Flag(*values)¶

Bases: IntEnum

Unused = 1¶

Flags()¶

Hover = 2¶

Normal = 0¶

Selected = 1¶

class State(*values)¶

Bases: IntEnum

Hover = 2¶

Normal = 0¶

Selected = 1¶

Unused = 1¶

signal aboutToChange(text: str, id: str | None = None)¶

Emitted when the definition of the associated component is about to be changed by the item.

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 (Optional[str] = None)

calculateAutomaticLinkPoint(self, other: QgsModelComponentGraphicItem | None)¶

Returns the best link point to use for a link originating at a specified other item.

Parameters:

other (Optional[QgsModelComponentGraphicItem]) – item at other end of link

Returns:

calculated link point in item coordinates.
edge: item edge for calculated best link point

calculateAutomaticLinkPoint(self, point: QPointF) -> (QPointF, Qt.Edge) Returns the best link point to use for a link originating at a specified other point.

Parameters:

other – point for other end of link (in scene coordinates)

Return type:

(QPointF, Qt.Edge)

Returns:

calculated link point in item coordinates.
edge: item edge for calculated best link point

virtual canDeleteComponent(self) → bool¶

Returns True if the component can be deleted.

Return type:: bool

signal changed¶: Emitted when the definition of the associated component is changed by the item.

component(self) → QgsProcessingModelComponent | None¶

Returns the model component associated with this item.

Return type:: Optional[QgsProcessingModelComponent]

virtual deleteComponent(self)¶

Called when the component should be deleted.

The default implementation does nothing.

virtual editComment(self)¶

Called when the comment attached to the item should be edited.

The default implementation does nothing.

virtual editComponent(self)¶

Called when the component should be edited.

The default implementation does nothing.

abstract fillColor(self, state: QgsModelComponentGraphicItem.State) → QColor¶

Returns the fill color for the item for the specified state.

Parameters:: state (QgsModelComponentGraphicItem.State)
Return type:: QColor

virtual flags(self) → QgsModelComponentGraphicItem.Flag¶

Returns item flags.

Return type:: QgsModelComponentGraphicItem.Flag

font(self) → QFont¶

Returns the font used to render text in the item.

See also

setFont()

Return type:: QFont

virtual iconPicture(self) → QPicture¶

Returns a QPicture version of the item’s icon, if available.

Return type:: QPicture

virtual iconPixmap(self) → QPixmap¶

Returns a QPixmap version of the item’s icon, if available.

Return type:: QPixmap

incomingArrows(self) → list[QgsModelArrowItem]¶

Returns the list of incoming arrow items terminating at this item.

See also

outgoingArrows()

Added in version 4.2.

Return type:: list[QgsModelArrowItem]

itemRect(self, storedRect: bool = False) → QRectF¶

Returns the rectangle representing the body of the item.

Parameters:: storedRect (bool = False)
Return type:: QRectF

label(self) → str¶

Returns the item’s label text.

See also

setLabel()

Return type:: str

linkPoint(self, edge: Qt.Edge, index: int, incoming: bool) → QPointF¶

Returns the location of the link point with the specified index on the specified edge.

Parameters:

edge (Qt.Edge)
index (int)
incoming (bool)

Return type:

QPointF

virtual linkPointCount(self, edge: Qt.Edge) → int¶

Returns the number of link points associated with the component on the specified edge.

Parameters:: edge (Qt.Edge)
Return type:: int

virtual linkPointText(self, edge: Qt.Edge, index: int) → str¶

Returns the text to use for the link point with the specified index on the specified edge.

Parameters:

edge (Qt.Edge)
index (int)

Return type:

str

model(self) → QgsProcessingModelAlgorithm | None¶

Returns the model associated with this item.

Return type:: Optional[QgsProcessingModelAlgorithm]

moveComponentBy(self, dx: float, dy: float)¶

Moves the component by the specified dx and dy.

Warning

Call this method, not QGraphicsItem.moveBy!

Parameters:

dx (float)
dy (float)

outSocketAt(self, index: int) → QgsModelDesignerSocketGraphicItem | None¶

Returns the output socket graphics items at the specified index.

May return None if no corresponding output socket exists.

Added in version 3.44.

Parameters:: index (int)
Return type:: Optional[QgsModelDesignerSocketGraphicItem]

outgoingArrows(self) → list[QgsModelArrowItem]¶

Returns the list of outgoing arrow items originating at this item.

See also

incomingArrows()

Added in version 4.2.

Return type:: list[QgsModelArrowItem]

virtual outlineColor(self) → QColor¶

Returns the optional color for an outline effect around the item.

Returns an invalid color if the outline effect is not required.

Return type:: QColor

virtual paintBackground(self, painter: QPainter | None, option: QStyleOptionGraphicsItem | None, widget: QWidget | None = None)¶

Paints the background part of the graphic item.

Subclasses may override this to customize the background appearance.

Parameters:

painter (Optional[QPainter])
option (Optional[QStyleOptionGraphicsItem])
widget (Optional[QWidget] = None)

paintOutline(self, painter: QPainter | None, option: QStyleOptionGraphicsItem | None, widget: QWidget | None = None)¶

Paints the outline part of the graphic item.

Parameters:

painter (Optional[QPainter])
option (Optional[QStyleOptionGraphicsItem])
widget (Optional[QWidget] = None)

previewItemMove(self, dx: float, dy: float)¶

Shows a preview of moving the item from its stored position by dx, dy.

Parameters:

dx (float)
dy (float)

registerWidgetContextGenerator(self, generator: QgsProcessingWidgetContextGenerator | None)¶

Register a Processing widget context generator class that will be used to retrieve a widget context for the item when required.

Added in version 4.4.

Parameters:: generator (Optional[QgsProcessingWidgetContextGenerator])

signal repaintArrows¶: Emitted when item requests that all connected arrows are repainted.

signal requestModelRepaint¶: Emitted by the item to request a repaint of the parent model scene.

setFont(self, font: QFont)¶

Sets the font used to render text in the item.

See also

font()

Parameters:: font (QFont)

setItemRect(self, rect: QRectF)¶

Sets a new scene rect for the item.

Parameters:: rect (QRectF)

setLabel(self, label: str | None)¶

Returns the item’s label text.

See also

label()

Parameters:: label (Optional[str])

signal sizePositionChanged¶: Emitted when the item’s size or position changes.

state(self) → QgsModelComponentGraphicItem.State¶

Returns the item’s current state.

Return type:: QgsModelComponentGraphicItem.State

abstract strokeColor(self, state: QgsModelComponentGraphicItem.State) → QColor¶

Returns the stroke color for the item for the specified state.

Parameters:: state (QgsModelComponentGraphicItem.State)
Return type:: QColor

virtual strokeStyle(self, state: QgsModelComponentGraphicItem.State) → Qt.PenStyle¶

Returns the stroke style to use while rendering the outline of the item.

Parameters:: state (QgsModelComponentGraphicItem.State)
Return type:: Qt.PenStyle

abstract textColor(self, state: QgsModelComponentGraphicItem.State) → QColor¶

Returns the label text color for the item for the specified state.

Parameters:: state (QgsModelComponentGraphicItem.State)
Return type:: QColor

virtual titleAlignment(self) → Qt.AlignmentFlag¶

Returns the title alignment

Return type:: Qt.AlignmentFlag

truncatedTextForItem(self, text: str | None) → str¶

Truncates a text string so that it fits nicely within the item’s width, accounting for margins and interactive buttons.

Parameters:: text (Optional[str])
Return type:: str

signal updateArrowPaths¶: Emitted when item requires that all connected arrow paths are recalculated.

updateButtonPositions(self)¶: Updates the item’s button positions, based on the current item rect.

abstract updateStoredComponentPosition(self, pos: QPointF, size: QSizeF)¶

Updates the position and size stored in the model for the associated comment

Parameters:

pos (QPointF)
size (QSizeF)

view(self) → QgsModelGraphicsView | None¶

Returns the associated view.

Return type:: Optional[QgsModelGraphicsView]