Switch to PySide2 or PyQt5

README.md

@@ -15,7 +15,7 @@ Although this graph makes no sense, it shows the current look and feel:
 ## Code Example
 
 ```python
-from PySide import QtGui
+from PySide2 import QtWidgets
 from qtnodes import (Header, Node, InputKnob,
                      OutputKnob, NodeGraphWidget)
 
@@ -28,7 +28,7 @@ class Multiply(Node):
         self.addKnob(InputKnob(name="y"))
         self.addKnob(OutputKnob(name="value"))
 
-app = QtGui.QApplication([])
+app = QtWidgets.QApplication([])
 graph = NodeGraphWidget()
 graph.registerNodeClass(Multiply)
 graph.addNode(Multiply())

qtnodes/__main__.py

@@ -1,7 +1,6 @@
 """Manual tests."""
 
-from PySide import QtGui
-
+from .qtchooser import QtWidgets
 from .knob import InputKnob, OutputKnob
 from .header import Header
 from .node import Node
@@ -120,7 +119,7 @@ def __init__(self):
 
 
 def test():
-    app = QtGui.QApplication([])
+    app = QtWidgets.QApplication([])
 
     graph = NodeGraphWidget()
     graph.setGeometry(100, 100, 800, 600)

qtnodes/edge.py

@@ -2,16 +2,15 @@
 
 import os
 
-from PySide import QtGui
-from PySide import QtCore
+from .qtchooser import QtCore, QtGui, QtWidgets
 
 
 windows = os.name == "nt"
 
 DELETE_MODIFIER_KEY = QtCore.Qt.AltModifier if windows else QtCore.Qt.ControlModifier
 
 
-class Edge(QtGui.QGraphicsPathItem):
+class Edge(QtWidgets.QGraphicsPathItem):
     """A connection between two Knobs."""
 
     def __init__(self, **kwargs):
@@ -66,14 +65,14 @@ def updatePath(self):
         self.setPath(path)
 
     def paint(self, painter, option, widget):
-        """Paint Edge color depending on modifier key pressed or not."""    
-        mod = QtGui.QApplication.keyboardModifiers() == DELETE_MODIFIER_KEY
+        """Paint Edge color depending on modifier key pressed or not."""
+        mod = QtGui.QGuiApplication.keyboardModifiers() == DELETE_MODIFIER_KEY
         if mod:
             self.setPen(QtGui.QPen(self.removalColor, self.thickness))
         else:
             self.setPen(QtGui.QPen(self.lineColor, self.thickness))
 
-        self.setBrush(QtCore.Qt.NoBrush)
+        # self.setBrush(QtCore.Qt.NoBrush)
         self.setZValue(-1)
         super(Edge, self).paint(painter, option, widget)
 

qtnodes/header.py

@@ -1,12 +1,11 @@
 """Node header."""
 
-from PySide import QtGui
-from PySide import QtCore
+from .qtchooser import QtCore, QtGui, QtWidgets
 
 from .helpers import getTextSize
 
 
-class Header(QtGui.QGraphicsItem):
+class Header(QtWidgets.QGraphicsItem):
     """A Header is a child of a Node and gives it a title.
 
     Its width resizes automatically to match the Node's width.
@@ -21,7 +20,7 @@ def __init__(self, node, text, **kwargs):
 
     def boundingRect(self):
         nodebox = self.node.boundingRect()
-        rect = QtCore.QRect(self.x(),
+        rect = QtCore.QRectF(self.x(),
                             self.y(),
                             nodebox.width(),
                             self.h)

qtnodes/helpers.py

@@ -2,9 +2,7 @@
 
 import json
 
-from PySide import QtGui
-from PySide import QtCore
-
+from .qtchooser import QtCore, QtGui, QtWidgets
 
 def readFileContent(filePath):
     """Return the content of the file."""
@@ -14,12 +12,12 @@ def readFileContent(filePath):
 
 def toJson(serialized):
     """Return JSON string from given native Python datatypes."""
-    return json.dumps(serialized, encoding="utf-8", indent=4)
+    return json.dumps(serialized, indent=4)
 
 
 def fromJson(jsonString):
     """Return native Python datatypes from JSON string."""
-    return json.loads(jsonString, encoding="utf-8")
+    return json.loads(jsonString)
 
 
 def getTextSize(text, painter=None):

qtnodes/knob.py

@@ -1,7 +1,6 @@
 """Knob classes."""
 
-from PySide import QtGui
-from PySide import QtCore
+from .qtchooser import QtCore, QtGui, QtWidgets
 
 from .helpers import getTextSize
 from .exceptions import KnobConnectionError, UnknownFlowError
@@ -13,10 +12,10 @@
 FLOW_RIGHT_TO_LEFT = "flow_right_to_left"
 
 
-class Knob(QtGui.QGraphicsItem):
+class Knob(QtWidgets.QGraphicsItem):
     """A Knob is a socket of a Node and can be connected to other Knobs."""
 
-    def __init__(self, **kwargs):
+    def __init__(self, name = None, **kwargs):
         super(Knob, self).__init__(**kwargs)
         self.x = 0
         self.y = 0
@@ -50,7 +49,7 @@ def connectTo(self, knob):
         """Convenience method to connect this to another Knob.
 
         This creates an Edge and directly connects it, in contrast to the mouse
-        events that first create an Edge temporarily and only connect if the 
+        events that first create an Edge temporarily and only connect if the
         user releases on a valid target Knob.
         """
         if knob is self:
@@ -70,8 +69,8 @@ def connectTo(self, knob):
     def addEdge(self, edge):
         """Add the given Edge to the internal tracking list.
 
-        This is only one part of the Knob connection procedure. It enables us to 
-        later traverse the whole graph and to see how many connections there 
+        This is only one part of the Knob connection procedure. It enables us to
+        later traverse the whole graph and to see how many connections there
         currently are.
 
         Also make sure it is added to the QGraphicsScene, if not yet done.
@@ -93,15 +92,15 @@ def removeEdge(self, edge):
 
     def boundingRect(self):
         """Return the bounding box of this Knob."""
-        rect = QtCore.QRect(self.x,
+        rect = QtCore.QRectF(self.x,
                             self.y,
                             self.w,
                             self.h)
         return rect
 
     def highlight(self, toggle):
         """Toggle the highlight color on/off.
-        
+
         Store the old color in a new attribute, so it can be restored.
         """
         if toggle:
@@ -175,39 +174,40 @@ def mouseReleaseEvent(self, event):
 
             node = self.parentItem()
             scene = node.scene()
-            target = scene.itemAt(event.scenePos())
+            targets = scene.items(event.scenePos())
 
             try:
-                if self.newEdge and target:
-
-                    if self.newEdge.source is target:
-                        raise KnobConnectionError(
-                            "Can't connect a Knob to itself.")
+                if self.newEdge and targets:
 
-                    if isinstance(target, Knob):
-
-                        if type(self) == type(target):
+                    for target in targets:
+                        if self.newEdge.source is target:
                             raise KnobConnectionError(
-                                "Can't connect Knobs of same type.")
+                                "Can't connect a Knob to itself.")
+
+                        if isinstance(target, Knob):
 
-                        newConn = set([self, target])
-                        for edge in self.edges:
-                            existingConn = set([edge.source, edge.target])
-                            diff = existingConn.difference(newConn)
-                            if not diff:
+                            if type(self) == type(target):
                                 raise KnobConnectionError(
-                                    "Connection already exists.")
-                                return
-
-                        self.checkMaxConnections(target)
-
-                        print("finish edge")
-                        target.addEdge(self.newEdge)
-                        self.newEdge.target = target
-                        self.newEdge.updatePath()
-                        self.finalizeEdge(self.newEdge)
-                        self.newEdge = None
-                        return
+                                    "Can't connect Knobs of same type.")
+
+                            newConn = set([self, target])
+                            for edge in self.edges:
+                                existingConn = set([edge.source, edge.target])
+                                diff = existingConn.difference(newConn)
+                                if not diff:
+                                    raise KnobConnectionError(
+                                        "Connection already exists.")
+                                    return
+
+                            self.checkMaxConnections(target)
+
+                            print("finish edge")
+                            target.addEdge(self.newEdge)
+                            self.newEdge.target = target
+                            self.newEdge.updatePath()
+                            self.finalizeEdge(self.newEdge)
+                            self.newEdge = None
+                            return
 
                 raise KnobConnectionError(
                     "Edge creation cancelled by user.")

qtnodes/node.py

@@ -2,22 +2,24 @@
 
 import uuid
 
-from PySide import QtGui
-from PySide import QtCore
+from .qtchooser import QtCore, QtGui, QtWidgets
 
 from .helpers import getTextSize
 from .knob import Knob, InputKnob, OutputKnob
 from .exceptions import DuplicateKnobNameError
 
 
-class Node(QtGui.QGraphicsItem):
+class Node(QtWidgets.QGraphicsItem):
     """A Node is a container for a header and 0-n Knobs.
 
     It can be created, removed and modified by the user in the UI.
     """
-    def __init__(self, **kwargs):
+    def __init__(self, scene = None, **kwargs):
         super(Node, self).__init__(**kwargs)
 
+        if (scene):
+            scene.addItem(self)
+
         # This unique id is useful for serialization/reconstruction.
         self.uuid = str(uuid.uuid4())
 
@@ -34,8 +36,8 @@ def __init__(self, **kwargs):
         self.fillColor = QtGui.QColor(220, 220, 220)
 
         # General configuration.
-        self.setFlag(QtGui.QGraphicsItem.ItemIsSelectable)
-        self.setFlag(QtGui.QGraphicsItem.ItemIsMovable)
+        self.setFlag(QtWidgets.QGraphicsItem.ItemIsSelectable)
+        self.setFlag(QtWidgets.QGraphicsItem.ItemIsMovable)
 
         self.setCursor(QtCore.Qt.SizeAllCursor)
 
@@ -73,7 +75,7 @@ def boundingRect(self):
         active when hovering its Header, as otherwise there would be conflicts
         with the hover events for the Node's Knobs.
         """
-        rect = QtCore.QRect(self.x,
+        rect = QtCore.QRectF(self.x,
                             self.y,
                             self.w,
                             self.header.h)
@@ -112,7 +114,7 @@ def addHeader(self, header):
     def addKnob(self, knob):
         """Add the given Knob to this Node.
 
-        A Knob must have a unique name, meaning there can be no duplicates within 
+        A Knob must have a unique name, meaning there can be no duplicates within
         a Node (the displayNames are not constrained though).
 
         Assign ourselves as the Knob's parent item (which also will put it onto

qtnodes/qtchooser.py

@@ -0,0 +1,16 @@
+import sys
+
+try:
+    import PySide2
+    from PySide2 import QtGui, QtWidgets, QtCore
+    from PySide2.QtCore import Signal, Slot
+    print('Using PySide2 bindings')
+except:
+
+    try:
+        import PyQt5
+        from PyQt5 import QtGui, QtWidgets, QtCore
+        from PyQt5.QtCore import pyqtSignal as Signal, pyqtSlot as Slot
+        print('Using PyQt5 bindings')
+    except:
+        raise Exception('No Qt bindings found! Install PySide2 or PyQt5')

qtnodes/view.py

@@ -1,7 +1,6 @@
 """Custom QGraphicsView."""
 
-from PySide import QtGui
-from PySide import QtCore
+from .qtchooser import QtCore, QtGui, QtWidgets
 
 from .node import Node
 from .edge import Edge
@@ -11,7 +10,7 @@
 ALTERNATE_MODE_KEY = QtCore.Qt.Key.Key_Alt
 
 
-class GridView(QtGui.QGraphicsView):
+class GridView(QtWidgets.QGraphicsView):
     """This view will draw a grid in its background."""
 
     def __init__(self, *args, **kwargs):
@@ -31,8 +30,8 @@ def __init__(self, *args, **kwargs):
         self.setHorizontalScrollBarPolicy(QtCore.Qt.ScrollBarAlwaysOff)
         self.setVerticalScrollBarPolicy(QtCore.Qt.ScrollBarAlwaysOff)
 
-        self.setDragMode(QtGui.QGraphicsView.RubberBandDrag)
-        self.setTransformationAnchor(QtGui.QGraphicsView.AnchorUnderMouse)
+        self.setDragMode(QtWidgets.QGraphicsView.RubberBandDrag)
+        self.setTransformationAnchor(QtWidgets.QGraphicsView.AnchorUnderMouse)
 
     def nodes(self):
         """Return all Nodes in the scene."""
@@ -62,12 +61,12 @@ def keyReleaseEvent(self, event):
     def mousePressEvent(self, event):
         """Initiate custom panning using middle mouse button."""
         if event.button() == QtCore.Qt.MiddleButton:
-            self.setDragMode(QtGui.QGraphicsView.NoDrag)
+            self.setDragMode(QtWidgets.QGraphicsView.NoDrag)
             self.panning = True
             self.prevPos = event.pos()
             self.setCursor(QtCore.Qt.SizeAllCursor)
         elif event.button() == QtCore.Qt.LeftButton:
-            self.setDragMode(QtGui.QGraphicsView.RubberBandDrag)
+            self.setDragMode(QtWidgets.QGraphicsView.RubberBandDrag)
         super(GridView, self).mousePressEvent(event)
 
     def mouseMoveEvent(self, event):
@@ -89,7 +88,7 @@ def mouseReleaseEvent(self, event):
         super(GridView, self).mouseReleaseEvent(event)
 
     def wheelEvent(self, event):
-        positive = event.delta() >= 0
+        positive = event.angleDelta().y() >= 0
         zoom = self.zoomStep if positive else 1.0 / self.zoomStep
         self.scale(zoom, zoom)
 
@@ -111,13 +110,13 @@ def drawBackground(self, painter, rect):
 
         currentXPos = left
         while currentXPos <= right:
-            line = QtCore.QLine(currentXPos, top, currentXPos, bottom)
+            line = QtCore.QLineF(currentXPos, top, currentXPos, bottom)
             lines.append(line)
             currentXPos += self.xStep
 
         currentYPos = top
         while currentYPos <= bottom:
-            line = QtCore.QLine(left, currentYPos, right, currentYPos)
+            line = QtCore.QLineF(left, currentYPos, right, currentYPos)
             lines.append(line)
             currentYPos += self.yStep