Class: QgsMapLayerStyleManager

class qgis.core.QgsMapLayerStyleManager(layer: QgsMapLayer)

Bases: PyQt5.QtCore.QObject

Construct a style manager associated with a map layer (must not be None). The style manager will be parented to layer.

Management of styles for use with one map layer. Stored styles are identified by their names. The manager always keep track of which style of the stored ones is currently active. When the current style is changed, the new style is applied to the associated layer.

The class takes care of updating itself when the layer’s current style configuration changes. When some of layer style’s properties change (e.g. opacity / colors), the style manager will record them in the currently active style without any extra effort required.

When an instance is created, it creates “default” style (with empty name) recorded from the associated map layer and it is set as the current style. The instance must always contain at least one style (which is the current).

The style which is marked as current has no style data stored in its entry. This is to avoid duplication of data as all data is stored in map layer and can be retrieved easily. Also when saving, the entry for the current style will be saved with no data because everything is already saved by the map layer itself.

The class also features support for temporary change of the layer’s style, ideal for short-term use of a custom style followed by restoration of the original style (for example, when rendering a map with a different than current style).

New in version 2.8: Enums

Methods

addStyle Add a style with given name and data
addStyleFromLayer Add style by cloning the current one
childEvent
connectNotify
currentStyle Returns name of the current style
customEvent
disconnectNotify
isDefault Returns True if this is the default style
isSignalConnected
layer Gets pointer to the associated map layer
mapLayerStyles Gets available styles for the associated map layer.
readXml Read configuration (for project loading)
receivers
removeStyle Remove a stored style
renameStyle Rename a stored style to a different name
reset Reset the style manager to a basic state - with one default style which is set as current
restoreOverrideStyle Restore the original store after a call to setOverrideStyle()
sender
senderSignalIndex
setCurrentStyle Set a different style as the current style - will apply it to the layer
setOverrideStyle Temporarily apply a different style to the layer.
style Returns data of a stored style - accessed by its unique name
styles Returns list of all defined style names
timerEvent
writeXml Write configuration (for project saving)

Signals

currentStyleChanged Emitted when the current style has been changed [signal]
styleAdded Emitted when a new style has been added [signal]
styleRemoved Emitted when a style has been removed [signal]
styleRenamed Emitted when a style has been renamed [signal]

Attributes

addStyle(self, name: str, style: QgsMapLayerStyle) → bool

Add a style with given name and data

Returns:True on success (name is unique and style is valid)
addStyleFromLayer(self, name: str) → bool

Add style by cloning the current one

Returns:True on success
childEvent()
connectNotify()
currentStyle(self) → str

Returns name of the current style

currentStyleChanged

Emitted when the current style has been changed [signal]

customEvent()
disconnectNotify()
isDefault(self, styleName: str) → bool

Returns True if this is the default style

New in version 3.0.

isSignalConnected()
layer(self) → QgsMapLayer

Gets pointer to the associated map layer

mapLayerStyles(self) → object

Gets available styles for the associated map layer.

Returns:A map of map layer style by style name

New in version 3.0.

readXml(self, mgrElement: QDomElement)

Read configuration (for project loading)

receivers()
removeStyle(self, name: str) → bool

Remove a stored style

Returns:True on success (style exists and it is not the last one)
renameStyle(self, name: str, newName: str) → bool

Rename a stored style to a different name

Returns:True on success (style exists and new name is unique)
reset(self)

Reset the style manager to a basic state - with one default style which is set as current

restoreOverrideStyle(self) → bool

Restore the original store after a call to setOverrideStyle()

sender()
senderSignalIndex()
setCurrentStyle(self, name: str) → bool

Set a different style as the current style - will apply it to the layer

Returns:True on success
setOverrideStyle(self, styleDef: str) → bool

Temporarily apply a different style to the layer. The argument can be either a style name or a full QML style definition. Each call must be paired with restoreOverrideStyle()

style(self, name: str) → QgsMapLayerStyle

Returns data of a stored style - accessed by its unique name

styleAdded

Emitted when a new style has been added [signal]

styleRemoved

Emitted when a style has been removed [signal]

styleRenamed

Emitted when a style has been renamed [signal]

styles(self) → List[str]

Returns list of all defined style names

timerEvent()
writeXml(self, mgrElement: QDomElement)

Write configuration (for project saving)