title: qt+pyqt emitted dropped URL twice
body: <p>I've used QT-Designer to create a xml-File, which contains a LineEdit widget. In the script i've tried to emit the file-path via drag-drop. It works but st. is wrong: the url will be emitted twice and looks like: </p>
  
  <p>/D:/Qtfile:///D:/Qt</p>
  
  <p>i know similar topics like <a href="https://stackoverflow.com/questions/6424404/pyqt-event-emmitted-twice">PyQt event emmitted twice</a> are discussed in stackoverflow. but i cannot find my answer...maybe i miss it. Why twice? Why the first "file://" disappeared?</p>
  
  <p>If i dont use Qt-Designer and define a SubClass for drag-drop a text like class CustomEditLine(QLineEdit):... and then make the instance of QlineEdit in the main-Window, url will be emitted only once but still "/D:/Qt". 
  here is my code: </p>
  
  <pre><code>from PyQt5 import QtWidgets, uic
  from PyQt5.QtCore import QObject,QEvent
  import sys
  
  qtCreatorFile=".\\gui\\testdrop.ui"
  Ui_MainWindow, QtBaseClass = uic.loadUiType(qtCreatorFile)
  
  class QDropHandler(QObject):
      def __init__(self, parent=None):
          super(QDropHandler, self).__init__(parent) 
  
      def eventFilter(self, obj, event):
          if event.type() == QEvent.DragEnter:
              event.accept()
          if event.type() == QEvent.Drop:
              md = event.mimeData()
              if md.hasUrls():
                  for url in md.urls():                   
                      obj.setText(url.path())
                      break
              event.accept()
          return False
  
  class root_App(QtWidgets.QMainWindow, Ui_MainWindow):
      def __init__(self):
          super(root_App, self).__init__()
          self.setupUi(self)
          self.lineEdit_1.installEventFilter(QDropHandler(self))
  
  if __name__=="__main__":
      app= QtWidgets.QApplication(sys.argv)
      window=root_App()
      window.show()
      sys.exit(app.exec_())
  </code></pre>
  
  <p>and my ui-xml:</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="UTF-8"?&gt;
  &lt;ui version="4.0"&gt;
   &lt;class&gt;Form&lt;/class&gt;
   &lt;widget class="QWidget" name="Form"&gt;
    &lt;property name="geometry"&gt;
     &lt;rect&gt;
      &lt;x&gt;0&lt;/x&gt;
      &lt;y&gt;0&lt;/y&gt;
      &lt;width&gt;758&lt;/width&gt;
      &lt;height&gt;424&lt;/height&gt;
     &lt;/rect&gt;
    &lt;/property&gt;
    &lt;property name="acceptDrops"&gt;
     &lt;bool&gt;true&lt;/bool&gt;
    &lt;/property&gt;
    &lt;property name="windowTitle"&gt;
     &lt;string&gt;Form&lt;/string&gt;
    &lt;/property&gt;
    &lt;widget class="QLineEdit" name="lineEdit_1"&gt;
     &lt;property name="geometry"&gt;
      &lt;rect&gt;
       &lt;x&gt;40&lt;/x&gt;
       &lt;y&gt;140&lt;/y&gt;
       &lt;width&gt;691&lt;/width&gt;
       &lt;height&gt;20&lt;/height&gt;
      &lt;/rect&gt;
     &lt;/property&gt;
    &lt;/widget&gt;
   &lt;/widget&gt;
   &lt;resources/&gt;
   &lt;connections/&gt;
  &lt;/ui&gt;
  </code></pre>