Class: QgsLayerTreeViewBase

Base class for QTreeView widgets which display a layer tree.

The view updates expanded state of layer tree nodes and also listens to changes to expanded states in the layer tree.

Warning

Subclasses must take care to call both setLayerTreeModel() and QTreeView.setModel() in order to have a fully functional tree view. This is by design, as it permits use of a custom proxy model in the view.

See also

QgsLayerTreeView

Added in version 4.0.

Class Hierarchy

Base classes

QTreeView
QAbstractItemView
QAbstractScrollArea
QFrame
QWidget
QObject
QPaintDevice

Subclasses

QgsLayerTreeView

Extends QTreeView and provides additional functionality when working with a layer tree.

Methods

collapseAllNodes	Enhancement of QTreeView.collapseAll() that also records expanded state in layer tree nodes
currentGroupNode	Returns the current group node.
currentLayer	Returns the currently selected layer, or None if no layers is selected.
currentLegendNode	Gets current legend node.
currentNode	Returns the current node.
defaultActions	Gets access to the default actions that may be used with the tree view
expandAllNodes	Enhancement of QTreeView.expandAll() that also records expanded state in layer tree nodes
index2legendNode	Returns legend node for given view index.
index2node	Returns the layer tree node for given view index.
layerForIndex	Returns the map layer corresponding to a view index.
layerTreeModel	Returns the associated layer tree model.
layerTreeModelIndexToViewIndex	Returns the layer tree model index corresponding with a view index.
legendNode2index	Returns the view index for a given legend node.
legendNode2sourceIndex	Returns the layer tree source model index for a given legend node.
node2index	Returns the view model index for a given node.
node2sourceIndex	Returns the layer tree source model index for a given node.
onExpandedChanged	Called when the expanded state changes for a node.
onModelReset	Called when the model is reset.
selectedLayerNodes	Returns the list of selected nodes filtered to just layer nodes (QgsLayerTreeLayer).
selectedLayers	Returns the list of selected layers.
selectedLayersRecursive	Gets list of selected layers, including those that are not directly selected, but their ancestor groups is selected.
selectedLegendNodes	Returns the list of selected legend nodes.
selectedNodes	Returns the list of selected layer tree nodes.
setCurrentLayer	Sets the currently selected layer.
setCurrentNode	Sets the currently selected node.
setLayerTreeModel	Associates a layer tree model with the view.
updateExpandedStateFromNode	Updates the expanded state from a node.
updateExpandedStateToNode	Stores the expanded state to a node with matching index.
viewIndexToLayerTreeModelIndex	Returns the view index corresponding with a layer tree model index.

class qgis.gui.QgsLayerTreeViewBase

Bases: QTreeView

__init__(parent: QWidget | None = None)

Constructor for QgsLayerTreeViewBase

Parameters:

parent (Optional[QWidget] = None)

collapseAllNodes(self)

Enhancement of QTreeView.collapseAll() that also records expanded state in layer tree nodes

currentGroupNode(self) → QgsLayerTreeGroup | None

Returns the current group node.

If a layer is the current node, the function will return the layer’s parent group.

May be None.

Return type:

Optional[QgsLayerTreeGroup]

currentLayer(self) → QgsMapLayer | None

Returns the currently selected layer, or None if no layers is selected.

See also

setCurrentLayer()

Return type:

Optional[QgsMapLayer]

currentLegendNode(self) → QgsLayerTreeModelLegendNode | None

Gets current legend node. May be None if current node is not a legend node.

Return type:

Optional[QgsLayerTreeModelLegendNode]

currentNode(self) → QgsLayerTreeNode | None

Returns the current node.

May be None.

Return type:

Optional[QgsLayerTreeNode]

defaultActions(self) → QgsLayerTreeViewDefaultActions | None

Gets access to the default actions that may be used with the tree view

Return type:

Optional[QgsLayerTreeViewDefaultActions]

expandAllNodes(self)

Enhancement of QTreeView.expandAll() that also records expanded state in layer tree nodes

index2legendNode(self, index: QModelIndex) → QgsLayerTreeModelLegendNode | None

Returns legend node for given view index.

Returns None for invalid index.

Unlike QgsLayerTreeModel.index2legendNode(), calling this method correctly accounts for mapping the view indexes through the view’s proxy model to the source model.

Added in version 3.18.

Parameters:

index (QModelIndex)

Return type:

Optional[QgsLayerTreeModelLegendNode]

index2node(self, index: QModelIndex) → QgsLayerTreeNode | None

Returns the layer tree node for given view index.

Returns root node for an invalid index.

Returns None if index does not refer to a layer tree node (e.g. it is a legend node).

Unlike QgsLayerTreeViewBase.index2Node(), calling this method correctly accounts for mapping the view indexes through the view’s proxy model to the source model.

See also

node2index()

Added in version 3.18.

Parameters:

index (QModelIndex)

Return type:

Optional[QgsLayerTreeNode]

layerForIndex(self, index: QModelIndex) → QgsMapLayer | None

Returns the map layer corresponding to a view index.

This method correctly accounts for proxy models set on the tree view.

Returns None if the index does not correspond to a map layer.

Parameters:

index (QModelIndex)

Return type:

Optional[QgsMapLayer]

layerTreeModel(self) → QgsLayerTreeModel | None

Returns the associated layer tree model.

See also

setLayerTreeModel()

Return type:

Optional[QgsLayerTreeModel]

layerTreeModelIndexToViewIndex(self, index: QModelIndex) → QModelIndex

Returns the layer tree model index corresponding with a view index.

This method correctly accounts for proxy models set on the tree view.

See also

viewIndexToLayerTreeModelIndex()

Parameters:

index (QModelIndex)

Return type:

QModelIndex

legendNode2index(self, legendNode: QgsLayerTreeModelLegendNode | None) → QModelIndex

Returns the view index for a given legend node.

If the legend node does not belong to the layer tree, the result is undefined.

If the legend node belongs to the tree but it is filtered out, an invalid model index is returned.

Unlike QgsLayerTreeModel.legendNode2index(), calling this method correctly accounts for mapping the view indexes through the view’s proxy model to the source model.

Added in version 3.18.

Parameters:

legendNode (Optional[QgsLayerTreeModelLegendNode])

Return type:

QModelIndex

legendNode2sourceIndex(self, legendNode: QgsLayerTreeModelLegendNode | None) → QModelIndex

Returns the layer tree source model index for a given legend node.

If the legend node does not belong to the layer tree, the result is undefined.

If the legend node belongs to the tree but it is filtered out, an invalid model index is returned.

Warning

The returned index belongs the underlying layer tree model, and care should be taken to correctly map to a proxy index if a proxy model is in use.

See also

legendNode2index()

Added in version 3.18.

Parameters:

legendNode (Optional[QgsLayerTreeModelLegendNode])

Return type:

QModelIndex

node2index(self, node: QgsLayerTreeNode | None) → QModelIndex

Returns the view model index for a given node.

If the node does not belong to the layer tree, the result is undefined.

Unlike QgsLayerTreeModel.node2index(), calling this method correctly accounts for mapping the view indexes through the view’s proxy model to the source model.

See also

index2node()

Added in version 3.18.

Parameters:

node (Optional[QgsLayerTreeNode])

Return type:

QModelIndex

node2sourceIndex(self, node: QgsLayerTreeNode | None) → QModelIndex

Returns the layer tree source model index for a given node.

If the node does not belong to the layer tree, the result is undefined.

Warning

The returned index belongs the underlying layer tree model, and care should be taken to correctly map to a proxy index if a proxy model is in use.

See also

node2index()

Added in version 3.18.

Parameters:

node (Optional[QgsLayerTreeNode])

Return type:

QModelIndex

onExpandedChanged(self, node: QgsLayerTreeNode | None, expanded: bool)

Called when the expanded state changes for a node.

Parameters:

• node (Optional[QgsLayerTreeNode])

• expanded (bool)

onModelReset(self)

Called when the model is reset.

selectedLayerNodes(self) → List[QgsLayerTreeLayer]

Returns the list of selected nodes filtered to just layer nodes (QgsLayerTreeLayer).

See also

selectedNodes()

See also

selectedLayers()

See also

selectedLegendNodes()

Return type:

List[QgsLayerTreeLayer]

selectedLayers(self) → List[QgsMapLayer]

Returns the list of selected layers.

See also

selectedNodes()

See also

selectedLayerNodes()

See also

selectedLegendNodes()

Return type:

List[QgsMapLayer]

selectedLayersRecursive(self) → List[QgsMapLayer]

Gets list of selected layers, including those that are not directly selected, but their ancestor groups is selected. If we have a group with two layers L1, L2 and just the group node is selected, this method returns L1 and L2, while selectedLayers() returns an empty list.

Added in version 3.4.

Return type:

List[QgsMapLayer]

selectedLegendNodes(self) → List[QgsLayerTreeModelLegendNode]

Returns the list of selected legend nodes.

See also

selectedNodes()

See also

selectedLayerNodes()

Added in version 3.32.

Return type:

List[QgsLayerTreeModelLegendNode]

selectedNodes(self, skipInternal: bool = False) → List[QgsLayerTreeNode]

Returns the list of selected layer tree nodes.

Parameters:

skipInternal (bool = False) – If True, will ignore nodes which have an ancestor in the selection

See also

selectedLayerNodes()

See also

selectedLegendNodes()

See also

selectedLayers()

Return type:

List[QgsLayerTreeNode]

setCurrentLayer(self, layer: QgsMapLayer | None)

Sets the currently selected layer.

If layer is None then all layers will be deselected.

See also

currentLayer()

Parameters:

layer (Optional[QgsMapLayer])

setCurrentNode(self, node: QgsLayerTreeNode | None)

Sets the currently selected node.

If node is None then all nodes will be deselected.

See also

currentNode()

Added in version 3.40.

Parameters:

node (Optional[QgsLayerTreeNode])

setLayerTreeModel(self, model: QgsLayerTreeModel | None)

Associates a layer tree model with the view.

Warning

This does NOT explicitly set the view’s model, and a subsequent call to QTreeView.setModel() must be made. This is by design, as it permits use of a custom proxy model in the view.

See also

layerTreeModel()

Parameters:

model (Optional[QgsLayerTreeModel])

updateExpandedStateFromNode(self, node: QgsLayerTreeNode | None)

Updates the expanded state from a node.

Parameters:

node (Optional[QgsLayerTreeNode])

updateExpandedStateToNode(self, index: QModelIndex)

Stores the expanded state to a node with matching index.

Parameters:

index (QModelIndex)

viewIndexToLayerTreeModelIndex(self, index: QModelIndex) → QModelIndex

Returns the view index corresponding with a layer tree model index.

This method correctly accounts for proxy models set on the tree view.

See also

layerTreeModelIndexToViewIndex()

Parameters:

index (QModelIndex)

Return type:

QModelIndex