PyQt mouse events for QGraphicsView
mouseevent, pyqt, qgraphicsview, qt
Solution
`mousePressEvent` and other methods are not slots. You can't use `connect` on those methods. You need to install an event filter on your view's `viewport()` and catch events in your widget's `eventFilter` method.
See Event Filters.
Problem
I'm trying to get the coordinates of various mouse events from a QGraphicsView, but I can't figure out how to trigger them. In the end, I want to add a picture to the graphicsView and then draw on top of it. Ideally I would want the coordinates to have an origin in the top left ``` 0,0-------------------- | | | | | | | ``` test.py ``` import sys from PyQt4 import QtCore, QtGui, uic class test(QtGui.QMainWindow): def __init__(self): QtGui.QMainWindow.__init__(self) self.ui = uic.loadUi('test.ui', self) self.connect(self.ui.graphicsView, QtCore.SIGNAL("mousePressEvent()"), self.mouse_pressed) self.connect(self.ui.graphicsView, QtCore.SIGNAL("mouseMoveEvent()"), self.mouse_moved) self.connect(self.ui.graphicsView, QtCore.SIGNAL("mouseReleaseEvent()"), self.mouse_released) self.ui.show() def mouse_pressed(self): p = QtGui.QCursor.pos() print "pressed here: " + p.x() + ", " + p.y() def mouse_moved(self): p = QtGui.QCursor.pos() print "moved here: " + p.x() + ", " + p.y() def mouse_released(self): p = QtGui.QCursor.pos() print "released here: " + p.x() + ", " + p.y() def main(): app = QtGui.QApplication(sys.argv) ui = test() sys.exit(app.exec_()) if __name__ == '__main__': main() ``` test.ui ``` <?xml version="1.0" encoding="UTF-8"?> <ui version="4.0"> <class>MainWindow</class> <widget class="QMainWindow" name="MainWindow"> <property name="geometry"> <rect> <x>0</x> <y>0</y> <width>800</width> <height>600</height> </rect> </property> <property name="windowTitle"> <string>MainWindow</string> </property> <widget class="QWidget" name="centralwidget"> <layout class="QVBoxLayout" name="verticalLayout"> <item> <widget class="QGraphicsView" name="graphicsView"/> </item> </layout> </widget> <widget class="QMenuBar" name="menubar"> <property name="geometry"> <rect> <x>0</x> <y>0</y> <width>800</width> <height>22</height> </rect> </property> </widget> <widget class="QStatusBar" name="statusbar"/> </widget> <resources/> <connections/> </ui> ``` EDIT: this seems to work. the ellipse is no longer moveable, as the click event seems to take over. any ideas? ``` import sys from PyQt4 import QtCore, QtGui, uic class graphicsScene(QtGui.QGraphicsScene): def __init__ (self, parent=None): super(graphicsScene, self).__init__ (parent) def mousePressEvent(self, event): position = QtCore.QPointF(event.scenePos()) print "pressed here: " + str(position.x()) + ", " + str(position.y()) self.update() def mouseMoveEvent(self, event): position = QtCore.QPointF(event.scenePos()) print "moved here: " + str(position.x()) + ", " + str(position.y()) self.update() def mouseReleaseEvent(self, event): position = QtCore.QPointF(event.scenePos()) print "released here: " + str(position.x()) + ", " + str(position.y()) self.update() class test(QtGui.QMainWindow): def __init__(self): QtGui.QMainWindow.__init__(self) self.ui = uic.loadUi('test.ui', self) self.scene = graphicsScene() self.ui.graphicsView.setScene(self.scene) pen = QtGui.QPen(QtCore.Qt.red) brush = QtGui.QBrush(QtCore.Qt.blue) e = self.scene.addEllipse(10,10,100,100, pen, brush) e.setFlag(QtGui.QGraphicsItem.ItemIsMovable, True) self.ui.show() def main(): app = QtGui.QApplication(sys.argv) ui = test() sys.exit(app.exec_()) if __name__ == '__main__': main() ```