Implement warning message when you change material diameter

The undo functionality currently gives an error though. Investigating...

Contributes to issue CURA-2822.

cura/CuraApplication.py

@@ -1,5 +1,6 @@
-# Copyright (c) 2015 Ultimaker B.V.
+# Copyright (c) 2017 Ultimaker B.V.
 # Cura is released under the terms of the AGPLv3 or higher.
+
 from PyQt5.QtNetwork import QLocalServer
 from PyQt5.QtNetwork import QLocalSocket
 
@@ -62,6 +63,7 @@ from . import CameraImageProvider
 from . import MachineActionManager
 
 from cura.Settings.MachineManager import MachineManager
+from cura.Settings.MaterialManager import MaterialManager
 from cura.Settings.ExtruderManager import ExtruderManager
 from cura.Settings.UserChangesModel import UserChangesModel
 from cura.Settings.ExtrudersModel import ExtrudersModel
@@ -189,6 +191,7 @@ class CuraApplication(QtApplication):
 
         self._machine_action_manager = MachineActionManager.MachineActionManager()
         self._machine_manager = None    # This is initialized on demand.
+        self._material_manager = None
         self._setting_inheritance_manager = None
 
         self._additional_components = {} # Components to add to certain areas in the interface
@@ -640,6 +643,7 @@ class CuraApplication(QtApplication):
         # Initialise extruder so as to listen to global container stack changes before the first global container stack is set.
         ExtruderManager.getInstance()
         qmlRegisterSingletonType(MachineManager, "Cura", 1, 0, "MachineManager", self.getMachineManager)
+        qmlRegisterSingletonType(MaterialManager, "Cura", 1, 0, "MaterialManager", self.getMaterialManager)
         qmlRegisterSingletonType(SettingInheritanceManager, "Cura", 1, 0, "SettingInheritanceManager",
                          self.getSettingInheritanceManager)
 
@@ -665,6 +669,11 @@ class CuraApplication(QtApplication):
             self._machine_manager = MachineManager.createMachineManager()
         return self._machine_manager
 
+    def getMaterialManager(self, *args):
+        if self._material_manager is None:
+            self._material_manager = MaterialManager.createMaterialManager()
+        return self._material_manager
+
     def getSettingInheritanceManager(self, *args):
         if self._setting_inheritance_manager is None:
             self._setting_inheritance_manager = SettingInheritanceManager.createSettingInheritanceManager()

cura/Settings/MaterialManager.py

@@ -0,0 +1,56 @@
+# Copyright (c) 2017 Ultimaker B.V.
+# Cura is released under the terms of the AGPLv3 or higher.
+
+from PyQt5.QtCore import QObject, pyqtSlot #To expose data to QML.
+
+from UM.Logger import Logger
+from UM.Message import Message #To create a warning message about material diameter.
+from UM.i18n import i18nCatalog #Translated strings.
+from UM.Settings.ContainerRegistry import ContainerRegistry #To find the material containers we need.
+
+catalog = i18nCatalog("cura")
+
+##  Handles material-related data, processing requests to change them and
+#   providing data for the GUI.
+#
+#   TODO: Move material-related managing over from the machine manager to here.
+class MaterialManager(QObject):
+    ##  Creates the global values for the material manager to use.
+    def __init__(self, parent = None):
+        super().__init__(parent)
+
+        #Material diameter changed warning message.
+        self._material_diameter_warning_message = Message(catalog.i18nc("@info:status Has a cancel button next to it.",
+            "The selected material diameter causes the material to become incompatible with the current printer."))
+        self._material_diameter_warning_message.addAction("Undo", catalog.i18nc("@action:button", "Undo"), None, catalog.i18nc("@action", "Undo changing the material diameter."))
+        self._material_diameter_warning_message.actionTriggered = self._materialWarningMessageAction
+
+    ##  Creates an instance of the MaterialManager.
+    #
+    #   This should only be called by PyQt to create the singleton instance of
+    #   this class.
+    @staticmethod
+    def createMaterialManager(engine = None, script_engine = None):
+        return MaterialManager()
+
+    @pyqtSlot(str, str)
+    def showMaterialWarningMessage(self, material_id, previous_diameter):
+        self._material_diameter_warning_message.previous_diameter = previous_diameter #Make sure that the undo button can properly undo the action.
+        self._material_diameter_warning_message.material_id = material_id
+        self._material_diameter_warning_message.show()
+
+    ##  Called when clicking "undo" on the warning dialogue for disappeared
+    #   materials.
+    #
+    #   This executes the undo action, restoring the material diameter.
+    #
+    #   \param button The identifier of the button that was pressed.
+    def _materialWarningMessageAction(self, button):
+        if button == "Undo":
+            container_registry = ContainerRegistry.getInstance()
+            matches = container_registry.findInstanceContainers(type = "material", id = self._material_diameter_warning_message.material_id)
+            if matches:
+                matches[0].setMetaDataEntry("diameter", self._material_diameter_warning_message.previous_diameter)
+            #No matches? Then the material has been deleted in the meanwhile.
+        else:
+            Logger.log("w", "Unknown button action for material diameter warning message: {action}".format(action = button))

resources/qml/Preferences/MaterialView.qml

@@ -1,5 +1,5 @@
-// Copyright (c) 2016 Ultimaker B.V.
-// Uranium is released under the terms of the AGPLv3 or higher.
+// Copyright (c) 2017 Ultimaker B.V.
+// Cura is released under the terms of the AGPLv3 or higher.
 
 import QtQuick 2.1
 import QtQuick.Controls 1.3
@@ -168,8 +168,13 @@ TabView
                     {
                         // This does not use a SettingPropertyProvider, because we need to make the change to all containers
                         // which derive from the same base_file
+                        var old_diameter = Cura.ContainerManager.getContainerMetaDataEntry(base.containerId, "properties/diameter");
                         base.setMetaDataEntry("approximate_diameter", properties.approximate_diameter, Math.round(value).toString());
                         base.setMetaDataEntry("properties/diameter", properties.diameter, value);
+                        if (Cura.MachineManager.filterMaterialsByMachine && properties.approximate_diameter != Math.round(Cura.MachineManager.activeMachine.approximateMaterialDiameter).toString())
+                        {
+                            Cura.MaterialManager.showMaterialWarningMessage(base.containerId, old_diameter);
+                        }
                         Cura.ContainerManager.setContainerProperty(base.containerId, "material_diameter", "value", value);
                     }
                     onValueChanged: updateCostPerMeter()