How to lock LayoutItem layers in QGIS 3.0 using python?

Question

I am using the python console to interact with QGIS 3.0 and have accessed the layout manager using:

lomgr = QgsProject.instance().layoutManager()
lo = lomgr.layouts()[0]
myMapItem = lo.itemById('myMapItem')

I need to lock the layers programmatically as I would if I were using the LayoutManager UI (e.g., select the item, go to Item Properties tab, and check/uncheck the 'Lock Layers' checkbox). I can't find any way of doing this from the documentation (https://python.qgis.org/api/classQgsLayoutItem.html).

Answer 1

Call setLayers([layer1,layer2,...]) (https://qgis.org/pyqgis/3.0/core/Layout/QgsLayoutItemMap.html#qgis.core.QgsLayoutItemMap.setLayers) on the map item:

lomgr = QgsProject.instance().layoutManager()
lo = lomgr.layouts()[0]
myMapItem = lo.itemById('myMapItem')
myMapItem.setLayers([layer1, layer2])

• okiedev: Thanks for the response. I had tried that approach but setLocked() locks the LayoutItem itself from mouse interactions. I am trying to lock the layoutItem layers which is different. I have found the layer lock setting within the template XML but there doesn't appear to be a python function to perform the layer locks. I'll post more once I have more time to test. Thanks.

Answer 2

sure it is too late but others might find it useful:
The methods you were looking for were probably:

setLayers() 

and

storeCurrentLayerStyles() 

These are methods of class QgsLayoutItemMap.
Consider you have a map object called map1 of a QGIS - Project called project1. To lock all layers of map1 of the current layer tree you could:

map1.setLayers(project1.mapLayers().values())

and then

map1.storeCurrentLayerStyles()

To release the layers you could e.g. simply use an empty dictonary in the setLayers method:

map1.setLayers({})
map1.storeCurrentLayerStyles()

Hope it helped