python 3.x - pyqt5: why the mimeData().text() returns nothing? -

learning pyqt5 recently, i've tried drag qpushbutton learning tutorial drag & drop button widget, , made improvements place button more accurate, add mime = e.mimedata().text() x, y = mime.split(',') according @avaris question, found e.mimedata().text() returned nothing supposed coordinate of local position of cursor respect button, tried print(mime), , got blank line nothing, print(mime.split(',')) , got ['']。

here's code:

import sys pyqt5.qtwidgets import qpushbutton, qwidget, qapplication, qlabel pyqt5.qtcore import qt, qmimedata pyqt5.qtgui import qdrag pyqt5 import qtcore   class button(qpushbutton):      def __init__(self, title, parent):         super().__init__(title, parent)      def mousemoveevent(self, e):          if e.buttons() != qt.rightbutton:             return          mimedata = qmimedata()          drag = qdrag(self)         drag.setmimedata(mimedata)         dropaction = drag.exec_(qt.moveaction)      def mousepressevent(self, e):          qpushbutton.mousepressevent(self, e)          if e.button() == qt.leftbutton:             print('press')   class example(qwidget):      def __init__(self):         super().__init__()          self.initui()      def initui(self):          self.setacceptdrops(true)          self.button = button('button', self)         self.button.move(100, 65)          self.setwindowtitle('click or move')         self.setgeometry(300, 300, 280, 150)      def dragenterevent(self, e):          e.accept()      def dropevent(self, e):          position = e.pos()         mime = e.mimedata().text()         x, y = mime.split(',')          #print(mime.split(','))          self.button.move(position - qtcore.qpoint(int(x), int(y)))          e.setdropaction(qt.moveaction)         e.accept()   if __name__ == '__main__':      app = qapplication(sys.argv)     ex = example()     ex.show()     app.exec_() 

in answer of @avaris, notice set mimedata button position in mousemoveevent:

mimedata = qtcore.qmimedata() # simple string 'x,y' mimedata.settext('%d,%d' % (e.x(), e.y())) 

the mimedata not contain default. have set yourself! have @ documentation qmimedata see else can (other setting arbitrary text)