Add signals to signal that a material got changed or removed

The material models need to know this.

Contributes to issue CURA-6600.

cura/Machines/ContainerTree.py

@@ -6,6 +6,7 @@ from UM.Settings.ContainerRegistry import ContainerRegistry  # To listen to cont
 from UM.Settings.DefinitionContainer import DefinitionContainer
 from UM.Settings.Interfaces import ContainerInterface
 import cura.CuraApplication  # Imported like this to prevent circular dependencies.
+from UM.Signal import Signal
 from cura.Machines.MachineNode import MachineNode
 
 from typing import Dict, List, TYPE_CHECKING
@@ -30,6 +31,8 @@ class ContainerTree:
 
     def __init__(self) -> None:
         self.machines = {}  # type: Dict[str, MachineNode] # Mapping from definition ID to machine nodes.
+        self.materialsChanged = Signal()  # Emitted when any of the material nodes in the tree got changed.
+
         container_registry = ContainerRegistry.getInstance()
         container_registry.containerAdded.connect(self._machineAdded)
         self._loadAll()
@@ -58,6 +61,7 @@ class ContainerTree:
             definition_id = stack.definition.getId()
             if definition_id not in self.machines:
                 self.machines[definition_id] = MachineNode(definition_id)
+                self.machines[definition_id].materialsChanged.connect(self.materialsChanged)
 
         Logger.log("d", "Building the container tree took %s seconds",  time.time() - start_time)
         
@@ -70,3 +74,4 @@ class ContainerTree:
             return  # Already have this definition ID.
 
         self.machines[definition_id] = MachineNode(definition_id)
+        self.machines[definition_id].materialsChanged.connect(self.materialsChanged)

cura/Machines/MachineNode.py

@@ -4,6 +4,7 @@
 from typing import Dict, List
 
 from UM.Logger import Logger
+from UM.Signal import Signal
 from UM.Util import parseBool
 from UM.Settings.ContainerRegistry import ContainerRegistry  # To find all the variants for this machine.
 from cura.Machines.ContainerNode import ContainerNode
@@ -19,6 +20,8 @@ class MachineNode(ContainerNode):
         super().__init__(container_id)
         self.variants = {}  # type: Dict[str, VariantNode] # Mapping variant names to their nodes.
         self.global_qualities = {}  # type: Dict[str, QualityNode] # Mapping quality types to the global quality for those types.
+        self.materialsChanged = Signal()  # Emitted when one of the materials underneath this machine has been changed.
+
         container_registry = ContainerRegistry.getInstance()
         try:
             my_metadata = container_registry.findContainersMetadata(id = container_id)[0]
@@ -93,6 +96,7 @@ class MachineNode(ContainerNode):
             variant_name = variant["name"]
             if variant_name not in self.variants:
                 self.variants[variant_name] = VariantNode(variant["id"], machine = self)
+                self.variants[variant_name].materialsChanged.connect(self.materialsChanged)
 
         # Find the global qualities for this printer.
         global_qualities = container_registry.findInstanceContainersMetadata(type = "quality", definition = self.container_id, global_quality = True)  # First try specific to this printer.

cura/Machines/MaterialNode.py

@@ -5,6 +5,7 @@ from typing import Any, TYPE_CHECKING
 
 from UM.Settings.ContainerRegistry import ContainerRegistry
 from UM.Settings.Interfaces import ContainerInterface
+from UM.Signal import Signal
 from cura.Machines.ContainerNode import ContainerNode
 from cura.Machines.QualityNode import QualityNode
 
@@ -20,6 +21,8 @@ class MaterialNode(ContainerNode):
         super().__init__(container_id)
         self.variant = variant
         self.qualities = {}  # type: Dict[str, QualityNode] # Mapping container IDs to quality profiles.
+        self.materialChanged = Signal()  # Triggered when the material is removed or its metadata is updated.
+
         container_registry = ContainerRegistry.getInstance()
         my_metadata = container_registry.findContainersMetadata(id = container_id)[0]
         self.base_file = my_metadata["base_file"]
@@ -59,6 +62,7 @@ class MaterialNode(ContainerNode):
             # Remove myself from my parent.
             if self.base_file in self.variant.materials:
                 del self.variant.materials[self.base_file]
+            self.materialChanged.emit(self)
 
     ##  Triggered when any metadata changed in any container, but only handles
     #   it when the metadata of this node is changed.
@@ -85,3 +89,4 @@ class MaterialNode(ContainerNode):
         if self.base_file != old_base_file or self.material_type != old_material_type or self.guid != old_guid:  # List of quality profiles could've changed.
             self.qualities = {}
             self._loadAll()  # Re-load the quality profiles for this node.
+        self.materialChanged.emit(self)

cura/Machines/VariantNode.py

@@ -5,6 +5,7 @@ from typing import TYPE_CHECKING
 
 from UM.Settings.ContainerRegistry import ContainerRegistry
 from UM.Settings.Interfaces import ContainerInterface
+from UM.Signal import Signal
 from cura.Machines.ContainerNode import ContainerNode
 from cura.Machines.MaterialNode import MaterialNode
 
@@ -26,6 +27,8 @@ class VariantNode(ContainerNode):
         super().__init__(container_id)
         self.machine = machine
         self.materials = {}  # type: Dict[str, MaterialNode]  # Mapping material base files to their nodes.
+        self.materialsChanged = Signal()
+
         container_registry = ContainerRegistry.getInstance()
         self.variant_name = container_registry.findContainersMetadata(id = container_id)[0]["name"]  # Store our own name so that we can filter more easily.
         container_registry.containerAdded.connect(self._materialAdded)
@@ -55,6 +58,7 @@ class VariantNode(ContainerNode):
             base_file = material["base_file"]
             if base_file not in self.materials:
                 self.materials[base_file] = MaterialNode(material["id"], variant = self)
+                self.materials[base_file].materialChanged.connect(self.materialsChanged)
 
     ##  When a material gets added to the set of profiles, we need to update our
     #   tree here.
@@ -86,3 +90,4 @@ class VariantNode(ContainerNode):
                 return  # Original was already specific or just as unspecific as the new one.
 
         self.materials[base_file] = MaterialNode(container.getId(), variant = self)
+        self.materials[base_file].materialChanged.connect(self.materialsChanged)