单击按钮返回值

将file_path存储在类级别的变量中，然后在您的按钮click方法中更新该值。

self.file_path = Noneself.Button_open.clicked.connect(self.OpenTextFile)

接着，

def OpenTextFile(self):    dialog = QtGui.QFileDialog()    dialog.setWindowTitle("Choose a file to open")    dialog.setFileMode(QtGui.QFileDialog.ExistingFile)    dialog.setNameFilter("Text (*.txt);; All files (*.*)")    dialog.setViewMode(QtGui.QFileDialog.Detail)    filename = QtCore.QStringList()    if(dialog.exec_()):        file_name = dialog.selectedFiles()    plain_text = open(file_name[0]).read()    self.Editor.setPlainText(plain_text)    self.file_path = str(file_name[0])

还有你的

self.Button_save.clicked.connect(self.SaveTextFile(file_path))

应该

self.Button_save.clicked.connect(self.SaveTextFile)

然后在您的保存点击方法中

def SaveTextFile(self):    save(self.file_path)     # Your pre to save file