refactor drag n drop logic.

Author: jchanvfx

NodeGraphQt/base/graph.py

@@ -17,7 +17,7 @@
 from .model import NodeGraphModel
 from .node import NodeObject, BaseNode, BackdropNode
 from .port import Port
-from ..constants import (DRAG_DROP_ID,
+from ..constants import (URI_SCHEME, URN_SCHEME,
                          PIPE_LAYOUT_CURVED,
                          PIPE_LAYOUT_STRAIGHT,
                          PIPE_LAYOUT_ANGLE,
@@ -27,41 +27,6 @@
 from ..widgets.viewer import NodeViewer
 
 
-class QWidgetDrops(QtWidgets.QWidget):
-
-    def __init__(self):
-        super(QWidgetDrops, self).__init__()
-        self.setAcceptDrops(True)
-        self.setWindowTitle("NodeGraphQt")
-        self.setStyleSheet('''
-        QWidget {
-            background-color: rgb(55,55,55);
-            color: rgb(200,200,200);
-            border-width: 0px;
-            }''')
-
-    def dragEnterEvent(self, event):
-        if event.mimeData().hasUrls:
-            event.accept()
-        else:
-            event.ignore()
-
-    def dragMoveEvent(self, event):
-        if event.mimeData().hasUrls:
-            event.accept()
-        else:
-            event.ignore()
-
-    def dropEvent(self, event):
-        if event.mimeData().hasUrls:
-            event.setDropAction(QtCore.Qt.CopyAction)
-            event.accept()
-            for url in event.mimeData().urls():
-                self.import_session(url.toLocalFile())
-        else:
-            event.ignore()
-
-
 class NodeGraph(QtCore.QObject):
     """
     The ``NodeGraph`` class is the main controller for managing all nodes
@@ -315,23 +280,41 @@ def _on_node_data_dropped(self, data, pos):
         """
         called when data has been dropped on the viewer.
 
+        Example Identifiers:
+            URI = ngqt://path/to/node/session.graph
+            URN = ngqt::node:com.chantasticvfx.MyNode
+
         Args:
             data (QtCore.QMimeData): mime data.
             pos (QtCore.QPoint): scene position relative to the drop.
         """
-
-        # don't emit signal for internal widget drops.
-        if data.hasFormat('text/plain'):
-            if data.text().startswith('<${}>:'.format(DRAG_DROP_ID)):
-                node_ids = data.text()[len('<${}>:'.format(DRAG_DROP_ID)):]
-                x, y = pos.x(), pos.y()
-                for node_id in node_ids.split(','):
-                    self.create_node(node_id, pos=[x, y])
-                x += 20
-                y += 20
-                return
-
-        self.data_dropped.emit(data, pos)
+        uri_regex = re.compile('{}(?:/*)([\w/]+)(\\.\w+)'.format(URI_SCHEME))
+        urn_regex = re.compile('{}([\w\\.:;]+)'.format(URN_SCHEME))
+        if data.hasFormat('text/uri-list'):
+            for url in data.urls():
+                local_file = url.toLocalFile()
+                if local_file:
+                    try:
+                        self.import_session(local_file)
+                        continue
+                    except Exception as e:
+                        pass
+
+                url_str = url.toString()
+                uri_search = uri_regex.search(url_str)
+                urn_search = urn_regex.search(url_str)
+                if uri_search:
+                    path = uri_search.group(1)
+                    ext = uri_search.group(2)
+                    self.import_session('{}{}'.format(path, ext))
+                elif urn_search:
+                    search_str = urn_search.group(1)
+                    node_ids = sorted(re.findall('node:([\w\\.]+)', search_str))
+                    for node_id in node_ids:
+                        x, y = pos.x(), pos.y()
+                        self.create_node(node_id, pos=[x, y])
+                        x += 20
+                        y += 20
 
     def _on_nodes_moved(self, node_data):
         """
@@ -450,9 +433,7 @@ def widget(self):
             PySide2.QtWidgets.QWidget: node graph widget.
         """
         if self._widget is None:
-            self._widget = QWidgetDrops()
-            self._widget.import_session = self.import_session
-
+            self._widget = QtWidgets.QWidget()
             layout = QtWidgets.QVBoxLayout(self._widget)
             layout.setContentsMargins(0, 0, 0, 0)
             layout.setSpacing(0)
@@ -1435,7 +1416,7 @@ def import_session(self, file_path):
 
         file_path = file_path.strip()
         if not os.path.isfile(file_path):
-            raise IOError('file does not exist.')
+            raise IOError('file does not exist: {}'.format(file_path))
 
         try:
             with open(file_path) as data_file:

NodeGraphQt/base/node.py

@@ -976,28 +976,32 @@ def delete_output(self, port):
 
     def set_ports(self, port_data):
         """
-        Set node input and output ports.
+        Set node input and output ports from specified port data.
+
+        example port data:
+            {
+                'input_ports':
+                    [{
+                        'name': 'input',
+                        'multi_connection': True,
+                        'display_name': 'Input',
+                        'data_type': 'NoneType',
+                        'locked': False
+                    }],
+                'output_ports':
+                    [{
+                        'name': 'output',
+                        'multi_connection': True,
+                        'display_name': 'Output',
+                        'data_type': 'NoneType',
+                        'locked': False
+                    }]
+            }
 
         Args:
             port_data(dict): port data.
         """
 
-        # port data eg.
-        # {
-        #     'input_ports':
-        #         [{'name': ...,
-        #           'multi_connection': ...,
-        #           'display_name': ...,
-        #           'data_type': ...
-        #           }, ...],
-        #     'output_ports':
-        #         [{'name': ...,
-        #           'multi_connection': ...,
-        #           'display_name': ...,
-        #           'data_type': ...
-        #           }, ...]
-        # }
-
         for port in self._inputs:
             self._view.delete_input(port.view)
             port.model.node = None

NodeGraphQt/constants.py

@@ -99,7 +99,8 @@
 VIEWER_GRID_COLOR = (45, 45, 45)
 VIEWER_GRID_SIZE = 50
 
-DRAG_DROP_ID = 'n0deGraphQT'
+URI_SCHEME = 'ngqt://'
+URN_SCHEME = 'ngqt::'
 
 # === PATHS ===
 

NodeGraphQt/widgets/node_tree.py

@@ -2,7 +2,7 @@
 # -*- coding: utf-8 -*-
 from Qt import QtWidgets, QtCore
 
-from ..constants import DRAG_DROP_ID
+from ..constants import URN_SCHEME
 
 TYPE_NODE = QtWidgets.QTreeWidgetItem.UserType + 1
 TYPE_CATEGORY = QtWidgets.QTreeWidgetItem.UserType + 2
@@ -40,9 +40,10 @@ def __repr__(self):
         return '<{} object at {}>'.format(self.__class__.__name__, hex(id(self)))
 
     def mimeData(self, items):
-        node_ids = ','.join(i.toolTip(0) for i in items)
+        node_ids = ['node:{}'.format(i.toolTip(0)) for i in items]
+        node_urn = URN_SCHEME + ';'.join(node_ids)
         mime_data = super(NodeTreeWidget, self).mimeData(items)
-        mime_data.setText('<${}>:{}'.format(DRAG_DROP_ID, node_ids))
+        mime_data.setUrls([node_urn])
         return mime_data
 
     def _build_tree(self):

NodeGraphQt/widgets/viewer.py

@@ -425,8 +425,11 @@ def mouseMoveEvent(self, event):
                     if isinstance(item, Pipe) and item.isVisible():
                         if not item.input_port:
                             continue
-                        if not item.input_port.node is node and \
-                                not item.output_port.node is node:
+                        port_node_check = all([
+                            not item.input_port.node is node,
+                            not item.output_port.node is node
+                        ])
+                        if port_node_check:
                             item.setSelected(True)
                             self.COLLIDING_state = True
                             break
@@ -446,18 +449,18 @@ def wheelEvent(self, event):
 
     def dropEvent(self, event):
         pos = self.mapToScene(event.pos())
-        event.setDropAction(QtCore.Qt.MoveAction)
+        event.setDropAction(QtCore.Qt.CopyAction)
         self.data_dropped.emit(
             event.mimeData(), QtCore.QPoint(pos.x(), pos.y()))
 
     def dragEnterEvent(self, event):
-        if event.mimeData().hasFormat('text/plain'):
+        if event.mimeData().hasFormat('text/uri-list'):
             event.accept()
         else:
             event.ignore()
 
     def dragMoveEvent(self, event):
-        if event.mimeData().hasFormat('text/plain'):
+        if event.mimeData().hasFormat('text/uri-list'):
             event.accept()
         else:
             event.ignore()