Merge branch 'CURA-6483_fix_add_by_ip' of github.com:Ultimaker/Cura into 4.1

cura/CuraApplication.py

@@ -117,6 +117,8 @@ from cura.UI.AddPrinterPagesModel import AddPrinterPagesModel
 from cura.UI.WelcomePagesModel import WelcomePagesModel
 from cura.UI.WhatsNewPagesModel import WhatsNewPagesModel
 
+from cura.Utils.NetworkingUtil import NetworkingUtil
+
 from .SingleInstance import SingleInstance
 from .AutoSave import AutoSave
 from . import PlatformPhysics
@@ -1028,6 +1030,8 @@ class CuraApplication(QtApplication):
         qmlRegisterSingletonType(SimpleModeSettingsManager, "Cura", 1, 0, "SimpleModeSettingsManager", self.getSimpleModeSettingsManager)
         qmlRegisterSingletonType(MachineActionManager.MachineActionManager, "Cura", 1, 0, "MachineActionManager", self.getMachineActionManager)
 
+        qmlRegisterType(NetworkingUtil, "Cura", 1, 5, "NetworkingUtil")
+
         qmlRegisterType(WelcomePagesModel, "Cura", 1, 0, "WelcomePagesModel")
         qmlRegisterType(WhatsNewPagesModel, "Cura", 1, 0, "WhatsNewPagesModel")
         qmlRegisterType(AddPrinterPagesModel, "Cura", 1, 0, "AddPrinterPagesModel")

cura/Machines/Models/DiscoveredPrintersModel.py

@@ -192,7 +192,7 @@ class DiscoveredPrintersModel(QObject):
     def discoveredPrintersByAddress(self) -> Dict[str, DiscoveredPrinter]:
         return self._discovered_printer_by_ip_dict
 
-    @pyqtProperty(list, notify = discoveredPrintersChanged)
+    @pyqtProperty("QVariantList", notify = discoveredPrintersChanged)
     def discoveredPrinters(self) -> List["DiscoveredPrinter"]:
         item_list = list(
             x for x in self._discovered_printer_by_ip_dict.values() if not parseBool(x.device.getProperty("temporary")))

cura/Machines/Models/GlobalStacksModel.py

@@ -5,6 +5,7 @@ from PyQt5.QtCore import Qt, QTimer
 
 from UM.Qt.ListModel import ListModel
 from UM.i18n import i18nCatalog
+from UM.Util import parseBool
 
 from cura.PrinterOutput.PrinterOutputDevice import ConnectionType
 from cura.Settings.CuraContainerRegistry import CuraContainerRegistry
@@ -54,7 +55,6 @@ class GlobalStacksModel(ListModel):
         items = []
 
         container_stacks = CuraContainerRegistry.getInstance().findContainerStacks(type = "machine")
-
         for container_stack in container_stacks:
             has_remote_connection = False
 
@@ -62,7 +62,7 @@ class GlobalStacksModel(ListModel):
                 has_remote_connection |= connection_type in [ConnectionType.NetworkConnection.value,
                                                              ConnectionType.CloudConnection.value]
 
-            if container_stack.getMetaDataEntry("hidden", False) in ["True", True]:
+            if parseBool(container_stack.getMetaDataEntry("hidden", False)):
                 continue
 
             section_name = "Network enabled printers" if has_remote_connection else "Local printers"

cura/Settings/GlobalStack.py

@@ -4,6 +4,8 @@
 from collections import defaultdict
 import threading
 from typing import Any, Dict, Optional, Set, TYPE_CHECKING, List
+import uuid
+
 from PyQt5.QtCore import pyqtProperty, pyqtSlot, pyqtSignal
 
 from UM.Decorators import override
@@ -34,6 +36,12 @@ class GlobalStack(CuraContainerStack):
 
         self.setMetaDataEntry("type", "machine")  # For backward compatibility
 
+        # TL;DR: If Cura is looking for printers that belong to the same group, it should use "group_id".
+        # Each GlobalStack by default belongs to a group which is identified via "group_id". This group_id is used to
+        # figure out which GlobalStacks are in the printer cluster for example without knowing the implementation
+        # details such as the um_network_key or some other identifier that's used by the underlying device plugin.
+        self.setMetaDataEntry("group_id", str(uuid.uuid4()))  # Assign a new GlobalStack to a unique group by default
+
         self._extruders = {}  # type: Dict[str, "ExtruderStack"]
 
         # This property is used to track which settings we are calculating the "resolve" for

cura/Settings/MachineManager.py

@@ -797,7 +797,6 @@ class MachineManager(QObject):
                 self.setActiveMachine(other_machine_stacks[0]["id"])
 
         metadata = CuraContainerRegistry.getInstance().findContainerStacksMetadata(id = machine_id)[0]
-        network_key = metadata.get("um_network_key", None)
         ExtruderManager.getInstance().removeMachineExtruders(machine_id)
         containers = CuraContainerRegistry.getInstance().findInstanceContainersMetadata(type = "user", machine = machine_id)
         for container in containers:
@@ -805,8 +804,9 @@ class MachineManager(QObject):
         CuraContainerRegistry.getInstance().removeContainer(machine_id)
 
         # If the printer that is being removed is a network printer, the hidden printers have to be also removed
-        if network_key:
+        group_id = metadata.get("group_id", None)
-            metadata_filter = {"um_network_key": network_key}
+        if group_id:
+            metadata_filter = {"group_id": group_id}
             hidden_containers = CuraContainerRegistry.getInstance().findContainerStacks(type = "machine", **metadata_filter)
             if hidden_containers:
                 # This reuses the method and remove all printers recursively
@@ -1360,21 +1360,24 @@ class MachineManager(QObject):
         # Get the definition id corresponding to this machine name
         machine_definition_id = CuraContainerRegistry.getInstance().findDefinitionContainers(name = machine_name)[0].getId()
         # Try to find a machine with the same network key
-        new_machine = self.getMachine(machine_definition_id, metadata_filter = {"um_network_key": self.activeMachineNetworkKey()})
+        metadata_filter = {"group_id": self._global_container_stack.getMetaDataEntry("group_id"),
+                           "um_network_key": self.activeMachineNetworkKey(),
+                           }
+        new_machine = self.getMachine(machine_definition_id, metadata_filter = metadata_filter)
         # If there is no machine, then create a new one and set it to the non-hidden instance
         if not new_machine:
             new_machine = CuraStackBuilder.createMachine(machine_definition_id + "_sync", machine_definition_id)
             if not new_machine:
                 return
+            new_machine.setMetaDataEntry("group_id", self._global_container_stack.getMetaDataEntry("group_id"))
             new_machine.setMetaDataEntry("um_network_key", self.activeMachineNetworkKey())
             new_machine.setMetaDataEntry("group_name", self.activeMachineNetworkGroupName)
-            new_machine.setMetaDataEntry("hidden", False)
             new_machine.setMetaDataEntry("connection_type", self._global_container_stack.getMetaDataEntry("connection_type"))
         else:
             Logger.log("i", "Found a %s with the key %s. Let's use it!", machine_name, self.activeMachineNetworkKey())
-            new_machine.setMetaDataEntry("hidden", False)
 
         # Set the current printer instance to hidden (the metadata entry must exist)
+        new_machine.setMetaDataEntry("hidden", False)
         self._global_container_stack.setMetaDataEntry("hidden", True)
 
         self.setActiveMachine(new_machine.getId())
@@ -1654,3 +1657,7 @@ class MachineManager(QObject):
         if results:
             machine_type_name = results[0]["name"]
         return machine_type_name
+
+    # Gets all machines that belong to the given group_id.
+    def getMachinesInGroup(self, group_id: str) -> List["GlobalStack"]:
+        return self._container_registry.findContainerStacks(type = "machine", group_id = group_id)

cura/UI/AddPrinterPagesModel.py

@@ -15,6 +15,7 @@ class AddPrinterPagesModel(WelcomePagesModel):
                             "page_url": self._getBuiltinWelcomePagePath("AddNetworkOrLocalPrinterContent.qml"),
                             "next_page_id": "machine_actions",
                             "next_page_button_text": self._catalog.i18nc("@action:button", "Add"),
+                            "previous_page_button_text": self._catalog.i18nc("@action:button", "Cancel"),
                             })
         self._pages.append({"id": "add_printer_by_ip",
                             "page_url": self._getBuiltinWelcomePagePath("AddPrinterByIpContent.qml"),

cura/UI/WelcomePagesModel.py

@@ -39,6 +39,7 @@ class WelcomePagesModel(ListModel):
     PageUrlRole = Qt.UserRole + 2  # URL to the page's QML file
     NextPageIdRole = Qt.UserRole + 3  # The next page ID it should go to
     NextPageButtonTextRole = Qt.UserRole + 4  # The text for the next page button
+    PreviousPageButtonTextRole = Qt.UserRole + 5  # The text for the previous page button
 
     def __init__(self, application: "CuraApplication", parent: Optional["QObject"] = None) -> None:
         super().__init__(parent)
@@ -47,6 +48,7 @@ class WelcomePagesModel(ListModel):
         self.addRoleName(self.PageUrlRole, "page_url")
         self.addRoleName(self.NextPageIdRole, "next_page_id")
         self.addRoleName(self.NextPageButtonTextRole, "next_page_button_text")
+        self.addRoleName(self.PreviousPageButtonTextRole, "previous_page_button_text")
 
         self._application = application
         self._catalog = i18nCatalog("cura")

cura/Utils/NetworkingUtil.py

@@ -0,0 +1,44 @@
+# Copyright (c) 2019 Ultimaker B.V.
+# Cura is released under the terms of the LGPLv3 or higher.
+
+import socket
+from typing import Optional
+
+from PyQt5.QtCore import QObject, pyqtSlot
+
+
+#
+# This is a QObject because some of the functions can be used (and are useful) in QML.
+#
+class NetworkingUtil(QObject):
+
+    def __init__(self, parent: Optional["QObject"] = None) -> None:
+        super().__init__(parent = parent)
+
+    # Checks if the given string is a valid IPv4 address.
+    @pyqtSlot(str, result = bool)
+    def isIPv4(self, address: str) -> bool:
+        try:
+            socket.inet_pton(socket.AF_INET, address)
+            result = True
+        except:
+            result = False
+        return result
+
+    # Checks if the given string is a valid IPv6 address.
+    @pyqtSlot(str, result = bool)
+    def isIPv6(self, address: str) -> bool:
+        try:
+            socket.inet_pton(socket.AF_INET6, address)
+            result = True
+        except:
+            result = False
+        return result
+
+    # Checks if the given string is a valid IPv4 or IPv6 address.
+    @pyqtSlot(str, result = bool)
+    def isValidIP(self, address: str) -> bool:
+        return self.isIPv4(address) or self.isIPv6(address)
+
+
+__all__ = ["NetworkingUtil"]

plugins/SliceInfoPlugin/MoreInfoWindow.qml

@@ -71,7 +71,7 @@ Window
                     left: parent.left
                     right: parent.right
                 }
-                text: catalog.i18nc("@text:window", "Ultimaker Cura collects anonymous data in order to improve the print quality and user experience. Below is an example of all the data that is sent:")
+                text: catalog.i18nc("@text:window", "Ultimaker Cura collects anonymous data in order to improve the print quality and user experience. Below is an example of all the data that is shared:")
                 wrapMode: Text.WordWrap
                 renderType: Text.NativeRendering
             }
@@ -106,7 +106,7 @@ Window
             Cura.RadioButton
             {
                 id: dontSendButton
-                text: catalog.i18nc("@text:window", "I don't want to send this data")
+                text: catalog.i18nc("@text:window", "I don't want to send anonymous data")
                 onClicked:
                 {
                     baseDialog.allowSendData = !checked
@@ -115,7 +115,7 @@ Window
             Cura.RadioButton
             {
                 id: allowSendButton
-                text: catalog.i18nc("@text:window", "Allow sending this data to Ultimaker and help us improve Cura")
+                text: catalog.i18nc("@text:window", "Allow sending anonymous data")
                 onClicked:
                 {
                     baseDialog.allowSendData = checked

plugins/UM3NetworkPrinting/resources/qml/DiscoverUM3Action.qml

@@ -1,8 +1,8 @@
-// Copyright (c) 2018 Ultimaker B.V.
+// Copyright (c) 2019 Ultimaker B.V.
 // Cura is released under the terms of the LGPLv3 or higher.
 
 import UM 1.2 as UM
-import Cura 1.0 as Cura
+import Cura 1.5 as Cura
 
 import QtQuick 2.2
 import QtQuick.Controls 1.1
@@ -14,9 +14,13 @@ Cura.MachineAction
 {
     id: base
     anchors.fill: parent;
+    property alias currentItemIndex: listview.currentIndex
     property var selectedDevice: null
     property bool completeProperties: true
 
+    // For validating IP addresses
+    property var networkingUtil: Cura.NetworkingUtil {}
+
     function connectToPrinter()
     {
         if(base.selectedDevice && base.completeProperties)
@@ -342,6 +346,17 @@ Cura.MachineAction
         }
     }
 
+    MessageDialog
+    {
+        id: invalidIPAddressMessageDialog
+        x: (parent.x + (parent.width) / 2) | 0
+        y: (parent.y + (parent.height) / 2) | 0
+        title: catalog.i18nc("@title:window", "Invalid IP address")
+        text: catalog.i18nc("@text", "Please enter a valid IP address.")
+        icon: StandardIcon.Warning
+        standardButtons: StandardButton.Ok
+    }
+
     UM.Dialog
     {
         id: manualPrinterDialog
@@ -404,6 +419,26 @@ Cura.MachineAction
                 text: catalog.i18nc("@action:button", "OK")
                 onClicked:
                 {
+                    // Validate the input first
+                    if (!networkingUtil.isValidIP(manualPrinterDialog.addressText))
+                    {
+                        invalidIPAddressMessageDialog.open()
+                        return
+                    }
+
+                    // if the entered IP address has already been discovered, switch the current item to that item
+                    // and do nothing else.
+                    for (var i = 0; i < manager.foundDevices.length; i++)
+                    {
+                        var device = manager.foundDevices[i]
+                        if (device.address == manualPrinterDialog.addressText)
+                        {
+                            currentItemIndex = i
+                            manualPrinterDialog.hide()
+                            return
+                        }
+                    }
+
                     manager.setManualDevice(manualPrinterDialog.printerKey, manualPrinterDialog.addressText)
                     manualPrinterDialog.hide()
                 }

plugins/UM3NetworkPrinting/src/DiscoverUM3Action.py

@@ -110,14 +110,12 @@ class DiscoverUM3Action(MachineAction):
         Logger.log("d", "Attempting to set the group name of the active machine to %s", group_name)
         global_container_stack = CuraApplication.getInstance().getGlobalContainerStack()
         if global_container_stack:
-            meta_data = global_container_stack.getMetaData()
+            # Update a GlobalStacks in the same group with the new group name.
-            if "group_name" in meta_data:
+            group_id = global_container_stack.getMetaDataEntry("group_id")
-                previous_connect_group_name = meta_data["group_name"]
+            machine_manager = CuraApplication.getInstance().getMachineManager()
-                global_container_stack.setMetaDataEntry("group_name", group_name)
+            for machine in machine_manager.getMachinesInGroup(group_id):
-                # Find all the places where there is the same group name and change it accordingly
+                machine.setMetaDataEntry("group_name", group_name)
-                self._replaceContainersMetadata(key = "group_name", value = previous_connect_group_name, new_value = group_name)
+
-            else:
-                global_container_stack.setMetaDataEntry("group_name", group_name)
             # Set the default value for "hidden", which is used when you have a group with multiple types of printers
             global_container_stack.setMetaDataEntry("hidden", False)
 
@@ -125,13 +123,6 @@ class DiscoverUM3Action(MachineAction):
             # Ensure that the connection states are refreshed.
             self._network_plugin.refreshConnections()
 
-    ##  Find all container stacks that has the pair 'key = value' in its metadata and replaces the value with 'new_value'
-    def _replaceContainersMetadata(self, key: str, value: str, new_value: str) -> None:
-        machines = CuraContainerRegistry.getInstance().findContainerStacks(type="machine")
-        for machine in machines:
-            if machine.getMetaDataEntry(key) == value:
-                machine.setMetaDataEntry(key, new_value)
-
     # Associates the currently active machine with the given printer device. The network connection information will be
     # stored into the metadata of the currently active machine.
     @pyqtSlot(QObject)

plugins/UM3NetworkPrinting/src/UM3OutputDevicePlugin.py

@@ -283,34 +283,24 @@ class UM3OutputDevicePlugin(OutputDevicePlugin):
 
         Logger.log("d", "Attempting to set the network key of the active machine to %s", printer_device.key)
 
-        global_container_stack = CuraApplication.getInstance().getGlobalContainerStack()
+        machine_manager = CuraApplication.getInstance().getMachineManager()
+        global_container_stack = machine_manager.activeMachine
         if not global_container_stack:
             return
 
-        meta_data = global_container_stack.getMetaData()
+        for machine in machine_manager.getMachinesInGroup(global_container_stack.getMetaDataEntry("group_id")):
+            machine.setMetaDataEntry("um_network_key", printer_device.key)
+            machine.setMetaDataEntry("group_name", printer_device.name)
 
-        if "um_network_key" in meta_data:  # Global stack already had a connection, but it's changed.
+            # Delete old authentication data.
-            old_network_key = meta_data["um_network_key"]
+            Logger.log("d", "Removing old authentication id %s for device %s",
-            # Since we might have a bunch of hidden stacks, we also need to change it there.
+                       global_container_stack.getMetaDataEntry("network_authentication_id", None), printer_device.key)
-            metadata_filter = {"um_network_key": old_network_key}
-            containers = self._application.getContainerRegistry().findContainerStacks(type = "machine", **metadata_filter)
 
-            for container in containers:
+            machine.removeMetaDataEntry("network_authentication_id")
-                container.setMetaDataEntry("um_network_key", printer_device.key)
+            machine.removeMetaDataEntry("network_authentication_key")
 
-                # Delete old authentication data.
+            # Ensure that these containers do know that they are configured for network connection
-                Logger.log("d", "Removing old authentication id %s for device %s",
+            machine.addConfiguredConnectionType(printer_device.connectionType.value)
-                           global_container_stack.getMetaDataEntry("network_authentication_id", None), printer_device.key)
-
-                container.removeMetaDataEntry("network_authentication_id")
-                container.removeMetaDataEntry("network_authentication_key")
-
-                # Ensure that these containers do know that they are configured for network connection
-                container.addConfiguredConnectionType(printer_device.connectionType.value)
-
-        else:  # Global stack didn't have a connection yet, configure it.
-            global_container_stack.setMetaDataEntry("um_network_key", printer_device.key)
-            global_container_stack.addConfiguredConnectionType(printer_device.connectionType.value)
 
         self.refreshConnections()
 

plugins/VersionUpgrade/VersionUpgrade40to41/VersionUpgrade40to41.py

@@ -3,6 +3,7 @@
 
 import configparser
 import io
+import uuid
 from typing import Dict, List, Tuple
 
 from UM.VersionUpgrade import VersionUpgrade
@@ -18,6 +19,7 @@ _renamed_quality_profiles = {
     "gmax15plus_pla_very_thick": "gmax15plus_global_very_thick"
 } # type: Dict[str, str]
 
+
 ##  Upgrades configurations from the state they were in at version 4.0 to the
 #   state they should be in at version 4.1.
 class VersionUpgrade40to41(VersionUpgrade):
@@ -95,6 +97,13 @@ class VersionUpgrade40to41(VersionUpgrade):
         if parser["containers"]["4"] in _renamed_quality_profiles:
             parser["containers"]["4"] = _renamed_quality_profiles[parser["containers"]["4"]]
 
+        # Assign a GlobalStack to a unique group_id. If the GlobalStack has a UM network connection, use the UM network
+        # key as the group_id.
+        if "um_network_key" in parser["metadata"]:
+            parser["metadata"]["group_id"] = parser["metadata"]["um_network_key"]
+        elif "group_id" not in parser["metadata"]:
+            parser["metadata"]["group_id"] = str(uuid.uuid4())
+
         result = io.StringIO()
         parser.write(result)
         return [filename], [result.getvalue()]

resources/qml/Cura.qml

@@ -795,7 +795,6 @@ UM.MainWindow
         title: catalog.i18nc("@title:window", "Add Printer")
         model: CuraApplication.getAddPrinterPagesModel()
         progressBarVisible: false
-        hasCancelButton: true
     }
 
     Cura.WizardDialog
@@ -804,7 +803,6 @@ UM.MainWindow
         title: catalog.i18nc("@title:window", "What's New")
         model: CuraApplication.getWhatsNewPagesModel()
         progressBarVisible: false
-        hasCancelButton: false
     }
 
     Connections

resources/qml/PrinterSelector/MachineSelectorList.qml

@@ -32,16 +32,7 @@ ListView
         width: listView.width
         outputDevice: Cura.MachineManager.printerOutputDevices.length >= 1 ? Cura.MachineManager.printerOutputDevices[0] : null
 
-        checked:
+        checked: Cura.MachineManager.activeMachineId == model.id
-        {
-            // If the machine has a remote connection
-            var result = Cura.MachineManager.activeMachineId == model.id
-            if (Cura.MachineManager.activeMachineHasRemoteConnection)
-            {
-                result |= Cura.MachineManager.activeMachineNetworkGroupName == model.metadata["group_name"]
-            }
-            return result
-        }
 
         onClicked:
         {

resources/qml/WelcomePages/AddNetworkOrLocalPrinterContent.qml

@@ -98,6 +98,20 @@ Item
         }
     }
 
+    // This "Back" button only shows in the "Add Machine" dialog, which has "previous_page_button_text" set to "Cancel"
+    Cura.SecondaryButton
+    {
+        id: backButton
+        anchors.left: parent.left
+        anchors.bottom: parent.bottom
+        visible: base.currentItem.previous_page_button_text ? true : false
+        text: base.currentItem.previous_page_button_text ? base.currentItem.previous_page_button_text : ""
+        onClicked:
+        {
+            base.endWizard()
+        }
+    }
+
     Cura.PrimaryButton
     {
         id: nextButton

resources/qml/WelcomePages/AddNetworkPrinterScrollView.qml

@@ -76,15 +76,28 @@ Item
 
                 Component.onCompleted:
                 {
-                    // Select the first one that's not "unknown" by default.
+                    var toSelectIndex = -1
+                    // Select the first one that's not "unknown" and is the host a group by default.
                     for (var i = 0; i < count; i++)
                     {
-                        if (!model[i].isUnknownMachineType)
+                        if (!model[i].isUnknownMachineType && model[i].isHostOfGroup)
                         {
-                            currentIndex = i
+                            toSelectIndex = i
                             break
                         }
                     }
+                    currentIndex = toSelectIndex
+                }
+
+                // CURA-6483 For some reason currentIndex can be reset to 0. This check is here to prevent automatically
+                // selecting an unknown or non-host printer.
+                onCurrentIndexChanged:
+                {
+                    var item = model[currentIndex]
+                    if (!item || item.isUnknownMachineType || !item.isHostOfGroup)
+                    {
+                        currentIndex = -1
+                    }
                 }
 
                 Component

resources/qml/WelcomePages/AddPrinterByIpContent.qml

@@ -6,7 +6,7 @@ import QtQuick.Controls 2.3
 import QtQuick.Layouts 1.3
 
 import UM 1.3 as UM
-import Cura 1.1 as Cura
+import Cura 1.5 as Cura
 
 
 //
@@ -22,9 +22,35 @@ Item
     property bool hasRequestInProgress: CuraApplication.getDiscoveredPrintersModel().hasManualDeviceRequestInProgress
     // Indicates if a request has finished.
     property bool hasRequestFinished: false
+    property string currentRequestAddress: ""
 
     property var discoveredPrinter: null
-    property var isPrinterDiscovered: discoveredPrinter != null
+    property bool isPrinterDiscovered: discoveredPrinter != null
+    // A printer can only be added if it doesn't have an unknown type and it's the host of a group.
+    property bool canAddPrinter: isPrinterDiscovered && !discoveredPrinter.isUnknownMachineType && discoveredPrinter.isHostOfGroup
+
+    // For validating IP address
+    property var networkingUtil: Cura.NetworkingUtil {}
+
+    // CURA-6483
+    // For a manually added UM printer, the UM3OutputDevicePlugin will first create a LegacyUM device for it. Later,
+    // when it gets more info from the printer, it will first REMOVE the LegacyUM device and then add a ClusterUM device.
+    // The Add-by-IP page needs to make sure that the user do not add an unknown printer or a printer that's not the
+    // host of a group. Because of the device list change, this page needs to react upon DiscoveredPrintersChanged so
+    // it has the correct information.
+    Connections
+    {
+        target: CuraApplication.getDiscoveredPrintersModel()
+        onDiscoveredPrintersChanged:
+        {
+            if (hasRequestFinished && currentRequestAddress)
+            {
+                var printer = CuraApplication.getDiscoveredPrintersModel().discoveredPrintersByAddress[currentRequestAddress]
+                printer = printer ? printer : null
+                discoveredPrinter = printer
+            }
+        }
+    }
 
     // Make sure to cancel the current request when this page closes.
     onVisibleChanged:
@@ -93,17 +119,36 @@ Item
                     anchors.verticalCenter: addPrinterButton.verticalCenter
                     anchors.left: parent.left
 
+                    signal invalidInputDetected()
+
+                    onInvalidInputDetected: invalidInputLabel.visible = true
+
                     validator: RegExpValidator
                     {
-                        regExp: /((^\s*((([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])\.){3}([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5]))\s*$)|(^\s*((([0-9A-Fa-f]{1,4}:){7}([0-9A-Fa-f]{1,4}|:))|(([0-9A-Fa-f]{1,4}:){6}(:[0-9A-Fa-f]{1,4}|((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3})|:))|(([0-9A-Fa-f]{1,4}:){5}(((:[0-9A-Fa-f]{1,4}){1,2})|:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3})|:))|(([0-9A-Fa-f]{1,4}:){4}(((:[0-9A-Fa-f]{1,4}){1,3})|((:[0-9A-Fa-f]{1,4})?:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}))|:))|(([0-9A-Fa-f]{1,4}:){3}(((:[0-9A-Fa-f]{1,4}){1,4})|((:[0-9A-Fa-f]{1,4}){0,2}:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}))|:))|(([0-9A-Fa-f]{1,4}:){2}(((:[0-9A-Fa-f]{1,4}){1,5})|((:[0-9A-Fa-f]{1,4}){0,3}:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}))|:))|(([0-9A-Fa-f]{1,4}:){1}(((:[0-9A-Fa-f]{1,4}){1,6})|((:[0-9A-Fa-f]{1,4}){0,4}:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}))|:))|(:(((:[0-9A-Fa-f]{1,4}){1,7})|((:[0-9A-Fa-f]{1,4}){0,5}:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}))|:)))(%.+)?\s*$))?/
+                        regExp: /([a-fA-F0-9.:]+)?/
                     }
 
+                    onTextEdited: invalidInputLabel.visible = false
+
                     placeholderText: catalog.i18nc("@text", "Place enter your printer's IP address.")
 
                     enabled: { ! (addPrinterByIpScreen.hasRequestInProgress || addPrinterByIpScreen.isPrinterDiscovered) }
                     onAccepted: addPrinterButton.clicked()
                 }
 
+                Label
+                {
+                    id: invalidInputLabel
+                    anchors.top: hostnameField.bottom
+                    anchors.topMargin: UM.Theme.getSize("default_margin").height
+                    anchors.left: parent.left
+                    visible: false
+                    text: catalog.i18nc("@text", "Please enter a valid IP address.")
+                    font: UM.Theme.getFont("default")
+                    color: UM.Theme.getColor("text")
+                    renderType: Text.NativeRendering
+                }
+
                 Cura.SecondaryButton
                 {
                     id: addPrinterButton
@@ -115,14 +160,21 @@ Item
                     onClicked:
                     {
                         const address = hostnameField.text
+                        if (!networkingUtil.isValidIP(address))
+                        {
+                            hostnameField.invalidInputDetected()
+                            return
+                        }
 
                         // This address is already in the discovered printer model, no need to add a manual discovery.
                         if (CuraApplication.getDiscoveredPrintersModel().discoveredPrintersByAddress[address])
                         {
                             addPrinterByIpScreen.discoveredPrinter = CuraApplication.getDiscoveredPrintersModel().discoveredPrintersByAddress[address]
+                            addPrinterByIpScreen.hasRequestFinished = true
                             return
                         }
 
+                        addPrinterByIpScreen.currentRequestAddress = address
                         CuraApplication.getDiscoveredPrintersModel().checkManualDevice(address)
                     }
                     busy: addPrinterByIpScreen.hasRequestInProgress
@@ -161,6 +213,8 @@ Item
                 Item
                 {
                     id: printerInfoLabels
+                    anchors.left: parent.left
+                    anchors.right: parent.right
                     anchors.top: parent.top
                     anchors.margins: UM.Theme.getSize("default_margin").width
 
@@ -177,10 +231,24 @@ Item
                         text: !addPrinterByIpScreen.isPrinterDiscovered ? "???" : addPrinterByIpScreen.discoveredPrinter.name
                     }
 
+                    Label
+                    {
+                        id: printerCannotBeAddedLabel
+                        width: parent.width
+                        anchors.top: printerNameLabel.bottom
+                        anchors.topMargin: UM.Theme.getSize("default_margin").height
+                        text: catalog.i18nc("@label", "This printer cannot be added because it's an unknown printer or it's not the host of a group.")
+                        visible: addPrinterByIpScreen.hasRequestFinished && !addPrinterByIpScreen.canAddPrinter
+                        font: UM.Theme.getFont("default_bold")
+                        color: UM.Theme.getColor("text")
+                        renderType: Text.NativeRendering
+                        wrapMode: Text.WordWrap
+                    }
+
                     GridLayout
                     {
                         id: printerInfoGrid
-                        anchors.top: printerNameLabel.bottom
+                        anchors.top: printerCannotBeAddedLabel ? printerCannotBeAddedLabel.bottom : printerNameLabel.bottom
                         anchors.margins: UM.Theme.getSize("default_margin").width
                         columns: 2
                         columnSpacing: UM.Theme.getSize("default_margin").width
@@ -253,7 +321,7 @@ Item
         }
     }
 
-    Cura.PrimaryButton
+    Cura.SecondaryButton
     {
         id: backButton
         anchors.left: parent.left
@@ -278,6 +346,6 @@ Item
             base.showNextPage()
         }
 
-        enabled: addPrinterByIpScreen.isPrinterDiscovered
+        enabled: addPrinterByIpScreen.canAddPrinter
     }
 }

resources/qml/WelcomePages/CloudContent.qml

@@ -35,7 +35,7 @@ Item
         horizontalAlignment: Text.AlignHCenter
         text: catalog.i18nc("@label", "Ultimaker Cloud")
         color: UM.Theme.getColor("primary_button")
-        font: UM.Theme.getFont("large_bold")
+        font: UM.Theme.getFont("huge")
         renderType: Text.NativeRendering
     }
 

resources/qml/WelcomePages/WizardDialog.qml

@@ -31,7 +31,6 @@ Window
 
     property var model: null  // Needs to be set by whoever is using this dialog.
     property alias progressBarVisible: wizardPanel.progressBarVisible
-    property alias hasCancelButton: cancelButton.visible
 
     onVisibilityChanged:
     {
@@ -54,21 +53,4 @@ Window
         target: model
         onAllFinished: dialog.hide()
     }
-
-    Cura.SecondaryButton
-    {
-        id: cancelButton
-
-        text: catalog.i18nc("@button", "Cancel")
-
-        visible: false
-
-        anchors.left: parent.left
-        anchors.bottom: parent.bottom
-        anchors.margins: UM.Theme.getSize("default_margin").width
-        anchors.leftMargin: UM.Theme.getSize("wide_margin").width
-
-        enabled: true
-        onClicked: dialog.visible = false
-    }
 }