对话框窗口中的标签不会更新按钮主窗口（PyQt）单击的每个版本

我使用QtDesigner设计了一个GUI（在eric4上）我刚刚创建了一个Qlabel作为占位符，它用于访问我正在构建的SQLite数据库的最新ID . 我希望它setlabel更改为ID主键中可用的下一个插槽，所以我在一个单独的py文件中创建了一个类和def：

class AccessMem:
def LastRowID(self):
    con = sqlite3.connect("Members.db") #access database
    cur = con.cursor()  #cursor object for database

    #created if first time to make a table
    try: 
        cur.execute('create table Members (ID integer primary key autoincrement not null, Nick string not null, NameFirst string, NameMiddle string, NameLast string, BirthMonth string, BirthDay string, BirthYear string, ContactNum string, EMail string, MailAdd string, MemberSince string)')
    except:
        pass

    #only to get the value of NextID to display
    TempNick = "ThisIsADummyNickToBeDeleted"        
    cur.execute("insert into Members (Nick) values (?)", (TempNick, ))
    NextID = cur.lastrowid 
    cur.execute("delete from Members where ID = ?",  (NextID, ))

    return NextID
    cur.close()
    con.close()

然后我修改了编译的UI表单并在顶部添加了这些表单（其中AccessMem函数的单独py文件是memberinfo.py）：

from memberinfo import *

IDL = AccessMem()
IDLabel = `IDL.LastRowID()`

然后我更改了 def retranslateUi 部分，其中显示必须更改为：

self.ID_Number.setText(IDLabel)

这样当对话窗口打开时它就会显示出来 .

Problem is that whenever I run the program and in the Main Window, launching for that Dialog Window, the display of the ID_Number is not updated in the Dialog Window. Whenever I close the program, run it again, then clicked again on the Main Window to launch the Dialog Window will the ID_Number display update.

以防万一，这里是主窗口中的对话框代码的一部分，我添加它来启动对话窗口：在顶部我添加：

from ui.newmember import NewMember

然后在AddMember点击的事件中：

def on_AddMember_clicked(self):
    """
    Slot documentation goes here.
    """
    # Open New Member window
    self.NM = NewMember()
    self.NM.show()

NewMember是ui文件夹中newmember.py中类的名称 .

只是注意到在NewMember对话窗口中，它基本上为sqlite数据库添加了一组新数据 . 如果单击“保存”按钮，以下是事件上对话框代码的部分：

def on_button_Save_released(self):
    """
    Slot documentation goes here.
    """
    Nik = unicode(self.LineEdit_Nickname.text())
    NFirst = unicode(self.LineEdit_NameFirst.text())
    NMid = unicode(self.LineEdit_NameMiddle.text())
    NLast = unicode(self.LineEdit_NameLast.text())
    BMon = unicode(self.ComboBox_BirthMonth.currentText())
    BDay = unicode(self.ComboBox_BirthDay.currentText())
    BYear = unicode(self.ComboBox_BirthYear.currentText())
    CNum = unicode(self.LineEdit_ContactNum.text())
    EM = unicode(self.LineEdit_EMail.text())
    MAd = unicode(self.LineEdit_MailAdd.text())

    self.NMem = NewMem()
    self.NMem.input_data(Nik,  NFirst, NMid,  NLast,  BMon,  BDay,  BYear,  CNum,  EM,  MAd)
    self.close()

input_data方法在一个单独的py文件中，如下所示：

class NewMem:
def input_data(self,  Nik,  NFirst, NMid,  NLast,  BMon,  BDay,  BYear,  CNum,  EM,  MAd):

    con = sqlite3.connect("Members.db") #access database
    cur = con.cursor()  #cursor object for database

    def adapt_datetime(ts):
        return time.mktime(ts.timetuple())

    #Get current time and date
    sqlite3.register_adapter(datetime.datetime, adapt_datetime) 
    now = datetime.datetime.now()  

    #created if first time to make a table
    try: 
        cur.execute('create table Members (ID integer primary key autoincrement not null, Nick string not null, NameFirst string, NameMiddle string, NameLast string, BirthMonth string, BirthDay string, BirthYear string, ContactNum string, EMail string, MailAdd string, MemberSince string)')
    except:
        pass

    cur.execute("insert into Members (Nick,NameFirst,NameMiddle,NameLast,BirthMonth,BirthDay,BirthYear,ContactNum,EMail,MailAdd,MemberSince) values (?,?,?,?,?,?,?,?,?,?,?)",(Nik,  NFirst, NMid,  NLast,  BMon,  BDay,  BYear,  CNum,  EM,  MAd, now))

    con.commit()
    cur.close()
    con.close()

因此，当单击NewMember Dialog Window的“Save”按钮时，Window将关闭，sqlite已插入新的数据集 . 然后在主窗口中的按钮启动NewMember窗口，IDLabel必须更新为最新的行ID，但它仍然没有更新自身 .

有可能问如何解决这个问题吗？深深地感谢任何帮助