Hi, I'm trying to understand graphics items, scenes, views, widgets, and not doing so well. I posted a question over on Stack Overflow, but probably should have tried here first.
The question, copied below, is from http://stackoverflow.com/questions/38749882/pyside-have-an-svg-image-follow-mouse-without-drag-and-drop I'm trying to place an SVG image in what will eventually be a QGroupBox in another application. Then, upon the first click over the SVG, the SVG "sticks" to the mouse (as if the mouse button was held down during a drag and drop). A second click will release ("drop") the image. I've been reading but not quite understanding the nature of / relationship between Widgets, Items, Scenes and Views. My code below sort of works but isn't quite right. The image almost actively avoids the mouse. Is there a clear explanation somewhere for non-C, non-C++, beginners with PyQt / PySide? Or is there a simple explanation for where I've gone wrong? #!/usr/bin/env python2 # -*- coding: utf-8 -*- import sys from PySide.QtCore import * from PySide.QtGui import * from PySide.QtSvg import * class Image(QGraphicsSvgItem): def __init__(self, parent=None): super(Image, self).__init__("image.svg", parent) self.parent = parent self.setFlags(QGraphicsItem.ItemIsSelectable | QGraphicsItem.ItemIsMovable) self.setAcceptsHoverEvents(True) self.svgSize = self.renderer().defaultSize() self.width = self.svgSize.width() self.height = self.svgSize.height() self.absolute = None # Image's absolute (global) position self.mobile = 0 # Initially immobile self.scene = None # Not in a scene yet self.view = None # Not in a view yet def hoverEnterEvent(self, event): print "Enter" def hoverLeaveEvent(self, event): print "Leave" def hoverMoveEvent(self, event): print "Moving" self.absolute = QCursor.pos() if self.view: relative = self.view.mapFromGlobal(self.absolute) if self.mobile: # self.setPos(relative) self.setPos(self.absolute) class Viewport(QGraphicsView): def __init__(self, parent=None): super(Viewport, self).__init__(parent) self.scene = QGraphicsScene() self.image = Image() self.image.setPos(100, 100) self.scene.addItem(self.image) self.setScene(self.scene) self.image.scene = self.scene self.image.view = self def mousePressEvent(self, event): super(Viewport, self).mousePressEvent(event) self.image.mobile = (self.image.mobile + 1) % 2 # Toggle mobility x = self.image.x() # + int(self.image.width / 2) y = self.image.y() # + int(self.image.height / 2) QCursor.setPos(x, y) relative = self.mapFromGlobal(self.image.absolute) print "absolute.x() = {0} absolute.y() = {1}"\ .format(self.image.absolute.x(), self.image.absolute.y()) print "relative.x() = {0} relative.y() = {1}"\ .format(relative.x(), relative.y()) class MainWindow(QWidget): def __init__(self, parent=None): super(MainWindow, self).__init__(parent) self.view = Viewport(self) hbox = QHBoxLayout() hbox.addWidget(self.view) self.setLayout(hbox) app = QApplication(sys.argv) window = MainWindow() window.show() sys.exit(app.exec_()) _______________________________________________ PySide mailing list PySide@qt-project.org http://lists.qt-project.org/mailman/listinfo/pyside
