import logging import math from qtpy.QtCore import QLineF, QPoint, QRectF, Qt from qtpy.QtGui import (QContextMenuEvent, QKeyEvent, QMouseEvent, QPainter, QPen, QShowEvent, QWheelEvent, QKeySequence) from qtpy.QtWidgets import (QAction, QGraphicsView, QLineEdit, QMenu, QTreeWidget, QTreeWidgetItem, QWidgetAction) from .connection_graphics_object import ConnectionGraphicsObject from .flow_scene import FlowScene from .node_graphics_object import NodeGraphicsObject logger = logging.getLogger(__name__) class FlowView(QGraphicsView): def __init__(self, scene, parent=None): super().__init__(parent=parent) self._clear_selection_action = None self._delete_selection_action = None self._scene = None self._click_pos = None self.setDragMode(QGraphicsView.ScrollHandDrag) self.setRenderHint(QPainter.Antialiasing) # setViewportUpdateMode(QGraphicsView.FullViewportUpdate) # setViewportUpdateMode(QGraphicsView.MinimalViewportUpdate) self.setHorizontalScrollBarPolicy(Qt.ScrollBarAlwaysOff) self.setVerticalScrollBarPolicy(Qt.ScrollBarAlwaysOff) self.setTransformationAnchor(QGraphicsView.AnchorUnderMouse) self.setCacheMode(QGraphicsView.CacheBackground) # setViewport(new QGLWidget(QGLFormat(QGL.SampleBuffers))) if scene is not None: self.setScene(scene) self._style = self._scene.style_collection self.setBackgroundBrush(self._style.flow_view.background_color) def clear_selection_action(self) -> QAction: """ Clear selection action Returns ------- value : QAction """ return self._clear_selection_action def delete_selection_action(self) -> QAction: """ Delete selection action Returns ------- value : QAction """ return self._delete_selection_action def setScene(self, scene: FlowScene): """ setScene Parameters ---------- scene : FlowScene """ self._scene = scene super().setScene(self._scene) # setup actions del self._clear_selection_action self._clear_selection_action = QAction("Clear Selection", self) self._clear_selection_action.setShortcut(QKeySequence.Cancel) self._clear_selection_action.triggered.connect(self._scene.clearSelection) self.addAction(self._clear_selection_action) del self._delete_selection_action self._delete_selection_action = QAction("Delete Selection", self) self._delete_selection_action.setShortcut(QKeySequence.Backspace) self._delete_selection_action.setShortcut(QKeySequence.Delete) self._delete_selection_action.triggered.connect(self.delete_selected) self.addAction(self._delete_selection_action) def scale_up(self): step = 1.2 factor = step ** 1.0 t = self.transform() if t.m11() <= 2.0: self.scale(factor, factor) def scale_down(self): step = 1.2 factor = step ** -1.0 self.scale(factor, factor) def delete_selected(self): # Delete the selected connections first, ensuring that they won't be # automatically deleted when selected nodes are deleted (deleting a node # deletes some connections as well) for item in self._scene.selectedItems(): if isinstance(item, ConnectionGraphicsObject): self._scene.delete_connection(item.connection) if not self._scene.allow_node_deletion: return # Delete the nodes; self will delete many of the connections. # Selected connections were already deleted prior to self loop, otherwise # qgraphicsitem_cast(item) could be a use-after-free # when a selected connection is deleted by deleting the node. for item in self._scene.selectedItems(): if isinstance(item, NodeGraphicsObject): self._scene.remove_node(item.node) def generate_context_menu(self, pos: QPoint): """ Generate a context menu for contextMenuEvent Parameters ---------- pos : QPoint The point where the context menu was requested """ model_menu = QMenu() skip_text = "skip me" # Add filterbox to the context menu txt_box = QLineEdit(model_menu) txt_box.setPlaceholderText("Filter") txt_box.setClearButtonEnabled(True) txt_box_action = QWidgetAction(model_menu) txt_box_action.setDefaultWidget(txt_box) model_menu.addAction(txt_box_action) # Add result treeview to the context menu tree_view = QTreeWidget(model_menu) tree_view.header().close() tree_view_action = QWidgetAction(model_menu) tree_view_action.setDefaultWidget(tree_view) model_menu.addAction(tree_view_action) top_level_items = {} for cat in self._scene.registry.categories(): item = QTreeWidgetItem(tree_view) item.setText(0, cat) item.setData(0, Qt.UserRole, skip_text) top_level_items[cat] = item registry = self._scene.registry for model, category in registry.registered_models_category_association().items(): self.parent = top_level_items[category] item = QTreeWidgetItem(self.parent) item.setText(0, model) item.setData(0, Qt.UserRole, model) tree_view.expandAll() def click_handler(item): model_name = item.data(0, Qt.UserRole) if model_name == skip_text: return try: model, _ = self._scene.registry.get_model_by_name(model_name) except ValueError: logger.error("Model not found: %s", model_name) else: node = self._scene.create_node(model) pos_view = self.mapToScene(pos) node.graphics_object.setPos(pos_view) self._scene.node_placed.emit(node) model_menu.close() tree_view.itemClicked.connect(click_handler) # Setup filtering def filter_handler(text): for name, top_lvl_item in top_level_items.items(): for i in range(top_lvl_item.childCount()): child = top_lvl_item.child(i) model_name = child.data(0, Qt.UserRole) child.setHidden(text not in model_name) txt_box.textChanged.connect(filter_handler) # make sure the text box gets focus so the user doesn't have to click on it txt_box.setFocus() return model_menu def contextMenuEvent(self, event: QContextMenuEvent): """ contextMenuEvent Parameters ---------- event : QContextMenuEvent """ if self.itemAt(event.pos()): super().contextMenuEvent(event) return elif not self._scene.allow_node_creation: return menu = self.generate_context_menu(event.pos()) menu.exec_(event.globalPos()) def wheelEvent(self, event: QWheelEvent): """ wheelEvent Parameters ---------- event : QWheelEvent """ delta = event.angleDelta() if delta.y() == 0: event.ignore() return d = delta.y() / abs(delta.y()) if d > 0.0: self.scale_up() else: self.scale_down() def keyPressEvent(self, event: QKeyEvent): """ keyPressEvent Parameters ---------- event : QKeyEvent """ if event.key() == Qt.Key_Shift: self.setDragMode(QGraphicsView.RubberBandDrag) super().keyPressEvent(event) def keyReleaseEvent(self, event: QKeyEvent): """ keyReleaseEvent Parameters ---------- event : QKeyEvent """ if event.key() == Qt.Key_Shift: self.setDragMode(QGraphicsView.ScrollHandDrag) super().keyReleaseEvent(event) def mousePressEvent(self, event: QMouseEvent): """ mousePressEvent Parameters ---------- event : QMouseEvent """ super().mousePressEvent(event) if event.button() == Qt.LeftButton: self._click_pos = self.mapToScene(event.pos()) def mouseMoveEvent(self, event: QMouseEvent): """ mouseMoveEvent Parameters ---------- event : QMouseEvent """ super().mouseMoveEvent(event) if self._scene.mouseGrabberItem() is None and event.buttons() == Qt.LeftButton: # Make sure shift is not being pressed if not (event.modifiers() & Qt.ShiftModifier): difference = self._click_pos - self.mapToScene(event.pos()) self.setSceneRect(self.sceneRect().translated(difference.x(), difference.y())) def drawBackground(self, painter: QPainter, r: QRectF): """ drawBackground Parameters ---------- painter : QPainter r : QRectF """ super().drawBackground(painter, r) def draw_grid(grid_step): window_rect = self.rect() tl = self.mapToScene(window_rect.topLeft()) br = self.mapToScene(window_rect.bottomRight()) left = math.floor(tl.x() / grid_step - 0.5) right = math.floor(br.x() / grid_step + 1.0) bottom = math.floor(tl.y() / grid_step - 0.5) top = math.floor(br.y() / grid_step + 1.0) # vertical lines lines = [ QLineF(xi * grid_step, bottom * grid_step, xi * grid_step, top * grid_step) for xi in range(int(left), int(right) + 1) ] # horizontal lines lines.extend( [QLineF(left * grid_step, yi * grid_step, right * grid_step, yi * grid_step) for yi in range(int(bottom), int(top) + 1) ] ) painter.drawLines(lines) style = self._style.flow_view # brush = self.backgroundBrush() pfine = QPen(style.fine_grid_color, 1.0) painter.setPen(pfine) draw_grid(15) p = QPen(style.coarse_grid_color, 1.0) painter.setPen(p) draw_grid(150) def showEvent(self, event: QShowEvent): """ showEvent Parameters ---------- event : QShowEvent """ self._scene.setSceneRect(QRectF(self.rect())) super().showEvent(event) @property def scene(self) -> FlowScene: """ Scene Returns ------- value : FlowScene """ return self._scene