#!/usr/bin/env python # -*- coding: utf-8 -*- # Created on 2018年7月26日 # author: Irony # site: https://pyqt5.com, https://github.com/892768447 # email: 892768447@qq.com # file: QGraphicsView练习.QGraphicsItem.ttt # description: __Author__ = """By: Irony QQ: 892768447 Email: 892768447@qq.com""" __Copyright__ = 'Copyright (c) 2018 Irony' __Version__ = 1.0 import sys from PyQt5.QtCore import Qt, QRectF, QPointF from PyQt5.QtGui import QBrush, QPainterPath, QPainter, QColor, QPen, QPixmap from PyQt5.QtWidgets import QGraphicsRectItem, QApplication, QGraphicsView, QGraphicsScene, QGraphicsItem class GraphicsRectItem(QGraphicsRectItem): handleTopLeft = 1 handleTopMiddle = 2 handleTopRight = 3 handleMiddleLeft = 4 handleMiddleRight = 5 handleBottomLeft = 6 handleBottomMiddle = 7 handleBottomRight = 8 handleSize = +8.0 handleSpace = -4.0 handleCursors = { handleTopLeft: Qt.SizeFDiagCursor, handleTopMiddle: Qt.SizeVerCursor, handleTopRight: Qt.SizeBDiagCursor, handleMiddleLeft: Qt.SizeHorCursor, handleMiddleRight: Qt.SizeHorCursor, handleBottomLeft: Qt.SizeBDiagCursor, handleBottomMiddle: Qt.SizeVerCursor, handleBottomRight: Qt.SizeFDiagCursor, } def __init__(self, *args): """ Initialize the shape. """ super().__init__(*args) self.handles = {} self.handleSelected = None self.mousePressPos = None self.mousePressRect = None self.setAcceptHoverEvents(True) self.setFlag(QGraphicsItem.ItemIsMovable, True) self.setFlag(QGraphicsItem.ItemIsSelectable, True) self.setFlag(QGraphicsItem.ItemSendsGeometryChanges, True) self.setFlag(QGraphicsItem.ItemIsFocusable, True) self.updateHandlesPos() def handleAt(self, point): """ Returns the resize handle below the given point. """ for k, v, in self.handles.items(): if v.contains(point): return k return None def hoverMoveEvent(self, moveEvent): """ Executed when the mouse moves over the shape (NOT PRESSED). """ if self.isSelected(): handle = self.handleAt(moveEvent.pos()) cursor = Qt.ArrowCursor if handle is None else self.handleCursors[handle] self.setCursor(cursor) super().hoverMoveEvent(moveEvent) def hoverLeaveEvent(self, moveEvent): """ Executed when the mouse leaves the shape (NOT PRESSED). """ self.setCursor(Qt.ArrowCursor) super().hoverLeaveEvent(moveEvent) def mousePressEvent(self, mouseEvent): """ Executed when the mouse is pressed on the item. """ self.handleSelected = self.handleAt(mouseEvent.pos()) if self.handleSelected: self.mousePressPos = mouseEvent.pos() self.mousePressRect = self.boundingRect() super().mousePressEvent(mouseEvent) def mouseMoveEvent(self, mouseEvent): """ Executed when the mouse is being moved over the item while being pressed. """ if self.handleSelected is not None: self.interactiveResize(mouseEvent.pos()) else: super().mouseMoveEvent(mouseEvent) def mouseReleaseEvent(self, mouseEvent): """ Executed when the mouse is released from the item. """ super().mouseReleaseEvent(mouseEvent) self.handleSelected = None self.mousePressPos = None self.mousePressRect = None self.update() def boundingRect(self): """ Returns the bounding rect of the shape (including the resize handles). """ o = self.handleSize + self.handleSpace return self.rect().adjusted(-o, -o, o, o) def updateHandlesPos(self): """ Update current resize handles according to the shape size and position. """ s = self.handleSize b = self.boundingRect() self.handles[self.handleTopLeft] = QRectF(b.left(), b.top(), s, s) self.handles[self.handleTopMiddle] = QRectF(b.center().x() - s / 2, b.top(), s, s) self.handles[self.handleTopRight] = QRectF(b.right() - s, b.top(), s, s) self.handles[self.handleMiddleLeft] = QRectF(b.left(), b.center().y() - s / 2, s, s) self.handles[self.handleMiddleRight] = QRectF(b.right() - s, b.center().y() - s / 2, s, s) self.handles[self.handleBottomLeft] = QRectF(b.left(), b.bottom() - s, s, s) self.handles[self.handleBottomMiddle] = QRectF(b.center().x() - s / 2, b.bottom() - s, s, s) self.handles[self.handleBottomRight] = QRectF(b.right() - s, b.bottom() - s, s, s) def interactiveResize(self, mousePos): """ Perform shape interactive resize. """ offset = self.handleSize + self.handleSpace boundingRect = self.boundingRect() rect = self.rect() diff = QPointF(0, 0) self.prepareGeometryChange() if self.handleSelected == self.handleTopLeft: fromX = self.mousePressRect.left() fromY = self.mousePressRect.top() toX = fromX + mousePos.x() - self.mousePressPos.x() toY = fromY + mousePos.y() - self.mousePressPos.y() diff.setX(toX - fromX) diff.setY(toY - fromY) boundingRect.setLeft(toX) boundingRect.setTop(toY) rect.setLeft(boundingRect.left() + offset) rect.setTop(boundingRect.top() + offset) self.setRect(rect) elif self.handleSelected == self.handleTopMiddle: fromY = self.mousePressRect.top() toY = fromY + mousePos.y() - self.mousePressPos.y() diff.setY(toY - fromY) boundingRect.setTop(toY) rect.setTop(boundingRect.top() + offset) self.setRect(rect) elif self.handleSelected == self.handleTopRight: fromX = self.mousePressRect.right() fromY = self.mousePressRect.top() toX = fromX + mousePos.x() - self.mousePressPos.x() toY = fromY + mousePos.y() - self.mousePressPos.y() diff.setX(toX - fromX) diff.setY(toY - fromY) boundingRect.setRight(toX) boundingRect.setTop(toY) rect.setRight(boundingRect.right() - offset) rect.setTop(boundingRect.top() + offset) self.setRect(rect) elif self.handleSelected == self.handleMiddleLeft: fromX = self.mousePressRect.left() toX = fromX + mousePos.x() - self.mousePressPos.x() diff.setX(toX - fromX) boundingRect.setLeft(toX) rect.setLeft(boundingRect.left() + offset) self.setRect(rect) elif self.handleSelected == self.handleMiddleRight: print("MR") fromX = self.mousePressRect.right() toX = fromX + mousePos.x() - self.mousePressPos.x() diff.setX(toX - fromX) boundingRect.setRight(toX) rect.setRight(boundingRect.right() - offset) self.setRect(rect) elif self.handleSelected == self.handleBottomLeft: fromX = self.mousePressRect.left() fromY = self.mousePressRect.bottom() toX = fromX + mousePos.x() - self.mousePressPos.x() toY = fromY + mousePos.y() - self.mousePressPos.y() diff.setX(toX - fromX) diff.setY(toY - fromY) boundingRect.setLeft(toX) boundingRect.setBottom(toY) rect.setLeft(boundingRect.left() + offset) rect.setBottom(boundingRect.bottom() - offset) self.setRect(rect) elif self.handleSelected == self.handleBottomMiddle: fromY = self.mousePressRect.bottom() toY = fromY + mousePos.y() - self.mousePressPos.y() diff.setY(toY - fromY) boundingRect.setBottom(toY) rect.setBottom(boundingRect.bottom() - offset) self.setRect(rect) elif self.handleSelected == self.handleBottomRight: fromX = self.mousePressRect.right() fromY = self.mousePressRect.bottom() toX = fromX + mousePos.x() - self.mousePressPos.x() toY = fromY + mousePos.y() - self.mousePressPos.y() diff.setX(toX - fromX) diff.setY(toY - fromY) boundingRect.setRight(toX) boundingRect.setBottom(toY) rect.setRight(boundingRect.right() - offset) rect.setBottom(boundingRect.bottom() - offset) self.setRect(rect) self.updateHandlesPos() def shape(self): """ Returns the shape of this item as a QPainterPath in local coordinates. """ path = QPainterPath() path.addRect(self.rect()) if self.isSelected(): for shape in self.handles.values(): path.addEllipse(shape) return path def paint(self, painter, option, widget=None): """ Paint the node in the graphic view. """ painter.setBrush(QBrush(QColor(255, 0, 0, 100))) painter.setPen(QPen(QColor(0, 0, 0), 1.0, Qt.SolidLine)) painter.drawRect(self.rect()) painter.setRenderHint(QPainter.Antialiasing) painter.setBrush(QBrush(QColor(255, 0, 0, 255))) painter.setPen(QPen(QColor(0, 0, 0, 255), 1.0, Qt.SolidLine, Qt.RoundCap, Qt.RoundJoin)) for handle, rect in self.handles.items(): if self.handleSelected is None or handle == self.handleSelected: painter.drawEllipse(rect) def main(): app = QApplication(sys.argv) grview = QGraphicsView() scene = QGraphicsScene() scene.setSceneRect(0, 0, 680, 459) scene.addPixmap(QPixmap('01.png')) grview.setScene(scene) item = GraphicsRectItem(0, 0, 300, 150) scene.addItem(item) grview.fitInView(scene.sceneRect(), Qt.KeepAspectRatio) grview.show() sys.exit(app.exec_()) if __name__ == '__main__': main()