python3+PyQt5 使用三种不同的简便项窗口部件显示数据的方法

本文通过将同一个数据集在三种不同的简便项窗口部件中显示。三个窗口的数据得到实时的同步,数据和视图分离。当添加或删除数据行，三个不同的视图均保持同步。数据将保存在本地文件中，而非数据库。对于小型和临时性数据集来说，这些简便窗口部件非常有用，可以用在非单独数据集中-数据自身的显示,编辑和存储。

所使用的数据集：

/home/yrd/eric_workspace/chap14/ships_conv/ships.py

#!/usr/bin/env python3

import platform
from PyQt5.QtCore import QDataStream, QFile,QIODevice,Qt
from PyQt5.QtWidgets import QApplication
NAME, OWNER, COUNTRY, DESCRIPTION, TEU = range(5)

MAGIC_NUMBER = 0x570C4
FILE_VERSION = 1

class Ship(object):

def __init__(self, name, owner, country, teu=0, description=""):
   self.name = name
   self.owner = owner
   self.country = country
   self.teu = teu
   self.description = description

def __hash__(self):
   return super(Ship, self).__hash__()

def __lt__(self, other):
   return bool(self.name.lower()<other.name.lower())

def __eq__(self, other):
   return bool(self.name.lower()==other.name.lower())

class ShipContainer(object):

def __init__(self, filename=""):
   self.filename = filename
   self.dirty = False
   self.ships = {}
   self.owners = set()
   self.countries = set()

def ship(self, identity):
   return self.ships.get(identity)

def addShip(self, ship):
   self.ships[id(ship)] = ship
   self.owners.add(str(ship.owner))
   self.countries.add(str(ship.country))
   self.dirty = True

def removeShip(self, ship):
   del self.ships[id(ship)]
   del ship
   self.dirty = True

def __len__(self):
   return len(self.ships)

def __iter__(self):
   for ship in self.ships.values():
     yield ship

def inOrder(self):
   return sorted(self.ships.values())

def inCountryOwnerOrder(self):
   return sorted(self.ships.values(),
          key=lambda x: (x.country, x.owner, x.name))

def load(self):
   exception = None
   fh = None
   try:
     if not self.filename:
       raise IOError("no filename specified for loading")
     fh = QFile(self.filename)
     if not fh.open(QIODevice.ReadOnly):
       raise IOError(str(fh.errorString()))
     stream = QDataStream(fh)
     magic = stream.readInt32()
     if magic != MAGIC_NUMBER:
       raise IOError("unrecognized file type")
     fileVersion = stream.readInt16()
     if fileVersion != FILE_VERSION:
       raise IOError("unrecognized file type version")
     self.ships = {}
     while not stream.atEnd():
       name = ""
       owner = ""
       country = ""
       description = ""
       name=stream.readQString()
       owner=stream.readQString()
       country=stream.readQString()
       description=stream.readQString()
       teu = stream.readInt32()
       ship = Ship(name, owner, country, teu, description)
       self.ships[id(ship)] = ship
       self.owners.add(str(owner))
       self.countries.add(str(country))
     self.dirty = False
   except IOError as e:
     exception = e
   finally:
     if fh is not None:
       fh.close()
     if exception is not None:
       raise exception

def save(self):
   exception = None
   fh = None
   try:
     if not self.filename:
       raise IOError("no filename specified for saving")
     fh = QFile(self.filename)
     if not fh.open(QIODevice.WriteOnly):
       raise IOError(str(fh.errorString()))
     stream = QDataStream(fh)
     stream.writeInt32(MAGIC_NUMBER)
     stream.writeInt16(FILE_VERSION)
     stream.setVersion(QDataStream.Qt_5_7)
     for ship in self.ships.values():
       stream.writeQString(ship.name)
       stream.writeQString(ship.owner)
       stream.writeQString(ship.country)
       stream.writeQString(ship.description)
       stream.writeInt32(ship.teu)
     self.dirty = False
   except IOError as e:
     exception = e
   finally:
     if fh is not None:
       fh.close()
     if exception is not None:
       raise exception

def generateFakeShips():
 for name, owner, country, teu, description in (
("Emma M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 151687,
"<b>W\u00E4rtsil\u00E4-Sulzer RTA96-C</b> main engine,"
"<font color=green>109,000 hp</font>"),
("MSC Pamela", "MSC", "Liberia", 90449,
"Draft <font color=green>15m</font>"),
("Colombo Express", "Hapag-Lloyd", "Germany", 93750,
"Main engine, <font color=green>93,500 hp</font>"),
("Houston Express", "Norddeutsche Reederei", "Germany", 95000,
"Features a <u>twisted leading edge full spade rudder</u>. "
"Sister of <i>Savannah Express</i>"),
("Savannah Express", "Norddeutsche Reederei", "Germany", 95000,
"Sister of <i>Houston Express</i>"),
("MSC Susanna", "MSC", "Liberia", 90449, ""),
("Eleonora M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 151687,
"Captain <i>Hallam</i>"),
("Estelle M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 151687,
"Captain <i>Wells</i>"),
("Evelyn M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 151687,
"Captain <i>Byrne</i>"),
("Georg M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 97933, ""),
("Gerd M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 97933, ""),
("Gjertrud M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 97933, ""),
("Grete M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 97933, ""),
("Gudrun M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 97933, ""),
("Gunvor M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 97933, ""),
("CSCL Le Havre", "Danaos Shipping", "Cyprus", 107200, ""),
("CSCL Pusan", "Danaos Shipping", "Cyprus", 107200,
"Captain <i>Watts</i>"),
("Xin Los Angeles", "China Shipping Container Lines (CSCL)",
"Hong Kong", 107200, ""),
("Xin Shanghai", "China Shipping Container Lines (CSCL)", "Hong Kong",
107200, ""),
("Cosco Beijing", "Costamare Shipping", "Greece", 99833, ""),
("Cosco Hellas", "Costamare Shipping", "Greece", 99833, ""),
("Cosco Guangzho", "Costamare Shipping", "Greece", 99833, ""),
("Cosco Ningbo", "Costamare Shipping", "Greece", 99833, ""),
("Cosco Yantian", "Costamare Shipping", "Greece", 99833, ""),
("CMA CGM Fidelio", "CMA CGM", "France", 99500, ""),
("CMA CGM Medea", "CMA CGM", "France", 95000, ""),
("CMA CGM Norma", "CMA CGM", "Bahamas", 95000, ""),
("CMA CGM Rigoletto", "CMA CGM", "France", 99500, ""),
("Arnold M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 93496,
"Captain <i>Morrell</i>"),
("Anna M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 93496,
"Captain <i>Lockhart</i>"),
("Albert M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 93496,
"Captain <i>Tallow</i>"),
("Adrian M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 93496,
"Captain <i>G. E. Ericson</i>"),
("Arthur M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 93496, ""),
("Axel M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 93496, ""),
("NYK Vega", "Nippon Yusen Kaisha", "Panama", 97825, ""),
("MSC Esthi", "MSC", "Liberia", 99500, ""),
("MSC Chicago", "Offen Claus-Peter", "Liberia", 90449, ""),
("MSC Bruxelles", "Offen Claus-Peter", "Liberia", 90449, ""),
("MSC Roma", "Offen Claus-Peter", "Liberia", 99500, ""),
("MSC Madeleine", "MSC", "Liberia", 107551, ""),
("MSC Ines", "MSC", "Liberia", 107551, ""),
("Hannover Bridge", "Kawasaki Kisen Kaisha", "Japan", 99500, ""),
("Charlotte M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 91690, ""),
("Clementine M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 91690, ""),
("Columbine M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 91690, ""),
("Cornelia M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 91690, ""),
("Chicago Express", "Hapag-Lloyd", "Germany", 93750, ""),
("Kyoto Express", "Hapag-Lloyd", "Germany", 93750, ""),
("Clifford M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 91690, ""),
("Sally M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 91690, ""),
("Sine M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 91690, ""),
("Skagen M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 91690, ""),
("Sofie M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 91690, ""),
("Sor\u00F8 M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 91690, ""),
("Sovereing M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 91690, ""),
("Susan M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 91690, ""),
("Svend M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 91690, ""),
("Svendborg M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 91690, ""),
("A.P. M\u00F8ller", "M\u00E6rsk Line", "Denmark", 91690,
"Captain <i>Ferraby</i>"),
("Caroline M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 91690, ""),
("Carsten M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 91690, ""),
("Chastine M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 91690, ""),
("Cornelius M\u00E6rsk", "M\u00E6rsk Line", "Denmark", 91690, ""),
("CMA CGM Otello", "CMA CGM", "France", 91400, ""),
("CMA CGM Tosca", "CMA CGM", "France", 91400, ""),
("CMA CGM Nabucco", "CMA CGM", "France", 91400, ""),
("CMA CGM La Traviata", "CMA CGM", "France", 91400, ""),
("CSCL Europe", "Danaos Shipping", "Cyprus", 90645, ""),
("CSCL Africa", "Seaspan Container Line", "Cyprus", 90645, ""),
("CSCL America", "Danaos Shipping ", "Cyprus", 90645, ""),
("CSCL Asia", "Seaspan Container Line", "Hong Kong", 90645, ""),
("CSCL Oceania", "Seaspan Container Line", "Hong Kong", 90645,
"Captain <i>Baker</i>"),
("M\u00E6rsk Seville", "Blue Star GmbH", "Liberia", 94724, ""),
("M\u00E6rsk Santana", "Blue Star GmbH", "Liberia", 94724, ""),
("M\u00E6rsk Sheerness", "Blue Star GmbH", "Liberia", 94724, ""),
("M\u00E6rsk Sarnia", "Blue Star GmbH", "Liberia", 94724, ""),
("M\u00E6rsk Sydney", "Blue Star GmbH", "Liberia", 94724, ""),
("MSC Heidi", "MSC", "Panama", 95000, ""),
("MSC Rania", "MSC", "Panama", 95000, ""),
("MSC Silvana", "MSC", "Panama", 95000, ""),
("M\u00E6rsk Stralsund", "Blue Star GmbH", "Liberia", 95000, ""),
("M\u00E6rsk Saigon", "Blue Star GmbH", "Liberia", 95000, ""),
("M\u00E6rsk Seoul", "Blue Star Ship Managment GmbH", "Germany",
95000, ""),
("M\u00E6rsk Surabaya", "Offen Claus-Peter", "Germany", 98400, ""),
("CMA CGM Hugo", "NSB Niederelbe", "Germany", 90745, ""),
("CMA CGM Vivaldi", "CMA CGM", "Bahamas", 90745, ""),
("MSC Rachele", "NSB Niederelbe", "Germany", 90745, ""),
("Pacific Link", "NSB Niederelbe", "Germany", 90745, ""),
("CMA CGM Carmen", "E R Schiffahrt", "Liberia", 89800, ""),
("CMA CGM Don Carlos", "E R Schiffahrt", "Liberia", 89800, ""),
("CMA CGM Don Giovanni", "E R Schiffahrt", "Liberia", 89800, ""),
("CMA CGM Parsifal", "E R Schiffahrt", "Liberia", 89800, ""),
("Cosco China", "E R Schiffahrt", "Liberia", 91649, ""),
("Cosco Germany", "E R Schiffahrt", "Liberia", 89800, ""),
("Cosco Napoli", "E R Schiffahrt", "Liberia", 89800, ""),
("YM Unison", "Yang Ming Line", "Taiwan", 88600, ""),
("YM Utmost", "Yang Ming Line", "Taiwan", 88600, ""),
("MSC Lucy", "MSC", "Panama", 89954, ""),
("MSC Maeva", "MSC", "Panama", 89954, ""),
("MSC Rita", "MSC", "Panama", 89954, ""),
("MSC Busan", "Offen Claus-Peter", "Panama", 89954, ""),
("MSC Beijing", "Offen Claus-Peter", "Panama", 89954, ""),
("MSC Toronto", "Offen Claus-Peter", "Panama", 89954, ""),
("MSC Charleston", "Offen Claus-Peter", "Panama", 89954, ""),
("MSC Vittoria", "MSC", "Panama", 89954, ""),
("Ever Champion", "NSB Niederelbe", "Marshall Islands", 90449,
"Captain <i>Phillips</i>"),
("Ever Charming", "NSB Niederelbe", "Marshall Islands", 90449,
"Captain <i>Tonbridge</i>"),
("Ever Chivalry", "NSB Niederelbe", "Marshall Islands", 90449, ""),
("Ever Conquest", "NSB Niederelbe", "Marshall Islands", 90449, ""),
("Ital Contessa", "NSB Niederelbe", "Marshall Islands", 90449, ""),
("Lt Cortesia", "NSB Niederelbe", "Marshall Islands", 90449, ""),
("OOCL Asia", "OOCL", "Hong Kong", 89097, ""),
("OOCL Atlanta", "OOCL", "Hong Kong", 89000, ""),
("OOCL Europe", "OOCL", "Hong Kong", 89097, ""),
("OOCL Hamburg", "OOCL", "Marshall Islands", 89097, ""),
("OOCL Long Beach", "OOCL", "Marshall Islands", 89097, ""),
("OOCL Ningbo", "OOCL", "Marshall Islands", 89097, ""),
("OOCL Shenzhen", "OOCL", "Hong Kong", 89097, ""),
("OOCL Tianjin", "OOCL", "Marshall Islands", 89097, ""),
("OOCL Tokyo", "OOCL", "Hong Kong", 89097, "")):
   yield Ship(name, owner, country, teu, description)

/home/yrd/eric_workspace/chap14/ships_conv/ships-dict.pyw

#!/usr/bin/env python3

import sys
from PyQt5.QtCore import QFile, QTimer, Qt
from PyQt5.QtWidgets import (QApplication, QDialog, QHBoxLayout, QLabel,
   QListWidget, QListWidgetItem, QMessageBox, QPushButton,
   QSplitter, QTableWidget, QTableWidgetItem, QTreeWidget,
   QTreeWidgetItem, QVBoxLayout, QWidget)
import ships

MAC = True
try:
 from PyQt5.QtGui import qt_mac_set_native_menubar
except ImportError:
 MAC = False

class MainForm(QDialog):

def __init__(self, parent=None):
   super(MainForm, self).__init__(parent)

listLabel = QLabel("&List")
   self.listWidget = QListWidget()
   listLabel.setBuddy(self.listWidget)

tableLabel = QLabel("&Table")
   self.tableWidget = QTableWidget()
   tableLabel.setBuddy(self.tableWidget)

treeLabel = QLabel("Tre&e")
   self.treeWidget = QTreeWidget()
   treeLabel.setBuddy(self.treeWidget)

addShipButton = QPushButton("&Add Ship")
   removeShipButton = QPushButton("&Remove Ship")
   quitButton = QPushButton("&Quit")
   if not MAC:
     addShipButton.setFocusPolicy(Qt.NoFocus)
     removeShipButton.setFocusPolicy(Qt.NoFocus)
     quitButton.setFocusPolicy(Qt.NoFocus)

splitter = QSplitter(Qt.Horizontal)
   vbox = QVBoxLayout()
   vbox.addWidget(listLabel)
   vbox.addWidget(self.listWidget)
   widget = QWidget()
   widget.setLayout(vbox)
   splitter.addWidget(widget)
   vbox = QVBoxLayout()
   vbox.addWidget(tableLabel)
   vbox.addWidget(self.tableWidget)
   widget = QWidget()
   widget.setLayout(vbox)
   splitter.addWidget(widget)
   vbox = QVBoxLayout()
   vbox.addWidget(treeLabel)
   vbox.addWidget(self.treeWidget)
   widget = QWidget()
   widget.setLayout(vbox)
   splitter.addWidget(widget)
   buttonLayout = QHBoxLayout()
   buttonLayout.addWidget(addShipButton)
   buttonLayout.addWidget(removeShipButton)
   buttonLayout.addStretch()
   buttonLayout.addWidget(quitButton)
   layout = QVBoxLayout()
   layout.addWidget(splitter)
   layout.addLayout(buttonLayout)
   self.setLayout(layout)

self.tableWidget.itemChanged[QTableWidgetItem].connect(self.tableItemChanged)
   addShipButton.clicked.connect(self.addShip)
   removeShipButton.clicked.connect(self.removeShip)
   quitButton.clicked.connect(self.accept)

self.ships = ships.ShipContainer("ships.dat")
   self.setWindowTitle("Ships (dict)")
   QTimer.singleShot(0, self.initialLoad)

def initialLoad(self):
   if not QFile.exists(self.ships.filename):
     for ship in ships.generateFakeShips():
       self.ships.addShip(ship)
     self.ships.dirty = False
   else:
     try:
       self.ships.load()
     except IOError as e:
       QMessageBox.warning(self, "Ships - Error",
           "Failed to load: {0}".format(e))
   self.populateList()
   self.populateTable()
   self.tableWidget.sortItems(0)
   self.populateTree()

def reject(self):
   self.accept()

def accept(self):
   if (self.ships.dirty and
     QMessageBox.question(self, "Ships - Save?",
         "Save unsaved changes?",
         QMessageBox.Yes|QMessageBox.No) ==
         QMessageBox.Yes):
     try:
       self.ships.save()
     except IOError as e:
       QMessageBox.warning(self, "Ships - Error",
           "Failed to save: {0}".format(e))
   QDialog.accept(self)

def populateList(self, selectedShip=None):
   selected = None
   self.listWidget.clear()
   for ship in self.ships.inOrder():
     item = QListWidgetItem("{0} of {1}/{2} ({3:,})".format(ship.name,ship.owner,ship.country,int(ship.teu)))
     self.listWidget.addItem(item)
     if selectedShip is not None and selectedShip == id(ship):
       selected = item
   if selected is not None:
     selected.setSelected(True)
     self.listWidget.setCurrentItem(selected)

def populateTable(self, selectedShip=None):
   selected = None
   self.tableWidget.clear()
   self.tableWidget.setSortingEnabled(False)
   self.tableWidget.setRowCount(len(self.ships))
   headers = ["Name", "Owner", "Country", "Description", "TEU"]
   self.tableWidget.setColumnCount(len(headers))
   self.tableWidget.setHorizontalHeaderLabels(headers)
   for row, ship in enumerate(self.ships):
     item = QTableWidgetItem(ship.name)
     item.setData(Qt.UserRole, id(ship))
     if selectedShip is not None and selectedShip == id(ship):
       selected = item
     self.tableWidget.setItem(row, ships.NAME, item)
     self.tableWidget.setItem(row, ships.OWNER,
         QTableWidgetItem(ship.owner))
     self.tableWidget.setItem(row, ships.COUNTRY,
         QTableWidgetItem(ship.country))
     self.tableWidget.setItem(row, ships.DESCRIPTION,
         QTableWidgetItem(ship.description))
     item = QTableWidgetItem("{0:>8}".format(ship.teu))
     item.setTextAlignment(Qt.AlignRight|Qt.AlignVCenter)
     self.tableWidget.setItem(row, ships.TEU, item)
   self.tableWidget.setSortingEnabled(True)
   self.tableWidget.resizeColumnsToContents()
   if selected is not None:
     selected.setSelected(True)
     self.tableWidget.setCurrentItem(selected)

def populateTree(self, selectedShip=None):
   selected = None
   self.treeWidget.clear()
   self.treeWidget.setColumnCount(2)
   self.treeWidget.setHeaderLabels(["Country/Owner/Name", "TEU"])
   self.treeWidget.setItemsExpandable(True)
   parentFromCountry = {}
   parentFromCountryOwner = {}
   for ship in self.ships.inCountryOwnerOrder():
     ancestor = parentFromCountry.get(ship.country)
     if ancestor is None:
       ancestor = QTreeWidgetItem(self.treeWidget, [ship.country])
       parentFromCountry[ship.country] = ancestor
     countryowner = ship.country + "/" + ship.owner
     parent = parentFromCountryOwner.get(countryowner)
     if parent is None:
       parent = QTreeWidgetItem(ancestor, [ship.owner])
       parentFromCountryOwner[countryowner] = parent
     item = QTreeWidgetItem(parent, [ship.name,"{0}".format(ship.teu)])
     item.setTextAlignment(1, Qt.AlignRight|Qt.AlignVCenter)
     if selectedShip is not None and selectedShip == id(ship):
       selected = item
     self.treeWidget.expandItem(parent)
     self.treeWidget.expandItem(ancestor)
   self.treeWidget.resizeColumnToContents(0)
   self.treeWidget.resizeColumnToContents(1)
   if selected is not None:
     selected.setSelected(True)
     self.treeWidget.setCurrentItem(selected)
   print(parentFromCountry)
   print(parentFromCountryOwner)

def addShip(self):
   ship = ships.Ship(" Unknown", " Unknown", " Unknown")
   self.ships.addShip(ship)
   self.populateList()
   self.populateTree()
   self.populateTable(id(ship))
   self.tableWidget.setFocus()
   self.tableWidget.editItem(self.tableWidget.currentItem())

def tableItemChanged(self, item):
   ship = self.currentTableShip()
   if ship is None:
     return
   column = self.tableWidget.currentColumn()
   if column == ships.NAME:
     ship.name = item.text().strip()
   elif column == ships.OWNER:
     ship.owner = item.text().strip()
   elif column == ships.COUNTRY:
     ship.country = item.text().strip()
   elif column == ships.DESCRIPTION:
     ship.description = item.text().strip()
   elif column == ships.TEU:
     ship.teu = item.text()
   self.ships.dirty = True
   self.populateList()
   self.populateTree()

def currentTableShip(self):
   item = self.tableWidget.item(self.tableWidget.currentRow(), 0)
   if item is None:
     return None
   return self.ships.ship(
       item.data(Qt.UserRole))

def removeShip(self):
   ship = self.currentTableShip()
   if ship is None:
     return
   if (QMessageBox.question(self, "Ships - Remove",
       "Remove {0} of {1}/{2}?".format(ship.name,ship.owner,ship.country),
       QMessageBox.Yes|QMessageBox.No) ==
       QMessageBox.No):
     return
   self.ships.removeShip(ship)
   self.populateList()
   self.populateTree()
   self.populateTable()

app = QApplication(sys.argv)
form = MainForm()
form.show()
app.exec_()

运行结果：

来源：https://blog.csdn.net/xiaoyangyang20/article/details/70213084