[ui] return command result after pushing it to the undo stack

this allows to directly retrieve, for instance, the node created by UIGraph.addNode method

meshroom/ui/commands.py

@@ -57,7 +57,7 @@ class UndoStack(QUndoStack):
         except Exception as e:
             logging.error("Error while trying command '{}': \n{}".format(command.text(), traceback.format_exc()))
             res = False
-        if res:
+        if res is not False:
             command.setEnabled(False)
             self.push(command)  # takes ownership
             command.setEnabled(True)
@@ -84,15 +84,17 @@ class GraphCommand(UndoCommand):
 
 
 class AddNodeCommand(GraphCommand):
-    def __init__(self, graph, nodeType, parent=None):
+    def __init__(self, graph, nodeType, parent=None, **kwargs):
         super(AddNodeCommand, self).__init__(graph, parent)
         self.nodeType = nodeType
         self.nodeName = None
+        self.kwargs = kwargs
 
     def redoImpl(self):
-        self.nodeName = self.graph.addNewNode(self.nodeType).name
+        node = self.graph.addNewNode(self.nodeType, **self.kwargs)
+        self.nodeName = node.name
         self.setText("Add Node {}".format(self.nodeName))
-        return True
+        return node
 
     def undoImpl(self):
         self.graph.removeNode(self.nodeName)

meshroom/ui/graph.py

@@ -210,7 +210,7 @@ class UIGraph(QObject):
         Args:
             command (commands.UndoCommand): the command to push
         """
-        self._undoStack.tryAndPush(command)
+        return self._undoStack.tryAndPush(command)
 
     def groupedGraphModification(self, title):
         """ Get a GroupedGraphModification for this Reconstruction.
@@ -223,9 +223,18 @@ class UIGraph(QObject):
         """
         return commands.GroupedGraphModification(self._graph, self._undoStack, title)
 
-    @Slot(str)
-    def addNode(self, nodeType):
-        self.push(commands.AddNodeCommand(self._graph, nodeType))
+    @Slot(str, result=QObject)
+    def addNode(self, nodeType, **kwargs):
+        """ [Undoable]
+        Create a new Node of type 'nodeType' and returns it.
+
+        Args:
+            nodeType (str): the type of the Node to create.
+            **kwargs: optional node attributes values
+        Returns:
+            Node: the created node
+        """
+        return self.push(commands.AddNodeCommand(self._graph, nodeType, **kwargs))
 
     @Slot(graph.Node)
     def removeNode(self, node):