如何在 PyQt 中的每个选项卡中分离显示和变量？

Question

我正在制作漫画查看器，但我遇到了问题。

所以我做了一个程序，每次我们点击“文件”然后“测试”时都会打开一个新标签。 当我们按下选项卡上的左右按钮时， self.i的值（打印在控制台中）会上下波动。

但是，问题是self.i的值会发生变化，无论我们在哪个选项卡上按下左右按钮， if self.i == 1仅显示在最后一个打开的选项卡上，我想显示的 label 。

我需要的是一种方法，让创建的每个选项卡都有自己的self.i和 label 根据它们自己的self.i值显示在任何选项卡上。 我不知道该怎么做。

这是单击“测试”时打开新选项卡的部分：

def Open(self):
    self.tab = QWidget()
    self.tab.layout = QGridLayout()
    self.nextpagebutton = QPushButton(">", self)
    self.nextpagebutton.setFixedSize(50, 780)
    self.tab.layout.addWidget(self.nextpagebutton, 0, 2)
    self.nextpagebutton.clicked.connect(self.readnext)

    self.prevpagebutton = QPushButton("<", self)
    self.prevpagebutton.setFixedSize(50, 780)
    self.tab.layout.addWidget(self.prevpagebutton, 0, 0)
    self.prevpagebutton.clicked.connect(self.readprev)

    self.n = int(self.n)+1
    self.tabs.addTab(self.tab, "Tab "+str(self.n))
    self.tab.setLayout(self.tab.layout)

这是当 self.i 等于 1 时显示 label 的部分：

    def readnext(self):
        self.i+=1
        if self.i == 1:
            self.label = QLabel("testtext")
            self.tab.layout.addWidget(self.label, 0, 1)
        print(self.i)

    def readprev(self):
        self.i-=1
        if self.i == 1:
            self.label = QLabel("testtext")
            self.tab.layout.addWidget(self.label, 0, 1)
        print(self.i)

这是我的完整程序，你可以试试，它有效：

import sys
from PyQt5.QtWidgets import QApplication, QMainWindow, QLabel, QGridLayout, QWidget, QPushButton, QAction, QStatusBar, QToolBar, QTabWidget
from PyQt5.QtCore import QCoreApplication


class FenetrePrincipale(QMainWindow):
    def __init__(self):
        super().__init__()
        self.setWindowTitle("Liseuse de Bandes Dessinées")
        self.left = 10
        self.top = 10
        self.width = 900
        self.height = 850
        self.i = 0

        self.setGeometry(self.left, self.top, self.width, self.height)

        self.toolbar = QToolBar("Toolbar")
        self.layout = QGridLayout()
        self.setCentralWidget(QWidget(self))
        self.centralWidget().setLayout(self.layout)
        self.move(200, 0)
        self.addToolBar(self.toolbar)

        self.table_widget = MyTableWidget(self)

        self.open = QAction("test", self)
        self.open.triggered.connect(self.table_widget.Open)

        self.setStatusBar(QStatusBar())
        self.menuFichier = self.menuBar().addMenu("&File")
        self.menuFichier.addAction(self.open)

        self.widget=QWidget()
        self.widget.setLayout(self.layout)
        self.setCentralWidget(self.widget)

        self.setCentralWidget(self.table_widget)

        self.show()

class MyTableWidget(QWidget):
    def __init__(self, parent=None):
        super(QWidget, self).__init__(parent)
        self.layout = QGridLayout()
        self.i = 0
        self.n = 0

        # Initialize tab screen
        self.tabs = QTabWidget()
        self.tabs.setDocumentMode(True)
        self.tabs.setMovable(True)

        # Add tabs to widget
        self.layout.addWidget(self.tabs)
        self.setLayout(self.layout)


    def Open(self):
        self.tab = QWidget()
        self.tab.layout = QGridLayout()
        self.nextpagebutton = QPushButton(">", self)
        self.nextpagebutton.setFixedSize(50, 780)
        self.tab.layout.addWidget(self.nextpagebutton, 0, 2)
        self.nextpagebutton.clicked.connect(self.readnext)

        self.prevpagebutton = QPushButton("<", self)
        self.prevpagebutton.setFixedSize(50, 780)
        self.tab.layout.addWidget(self.prevpagebutton, 0, 0)
        self.prevpagebutton.clicked.connect(self.readprev)

        self.n = int(self.n)+1
        self.tabs.addTab(self.tab, "Tab "+str(self.n))
        self.tab.setLayout(self.tab.layout)

    def readnext(self):
        self.i+=1
        if self.i == 1:
            self.label = QLabel("testtext")
            self.tab.layout.addWidget(self.label, 0, 1)
        print(self.i)

    def readprev(self):
        self.i-=1
        if self.i == 1:
            self.label = QLabel("testtext")
            self.tab.layout.addWidget(self.label, 0, 1)
        print(self.i)



app = QCoreApplication.instance()
if app is None:
    app = QApplication(sys.argv)

window = FenetrePrincipale()
window.show()

app.exec_()

Answer 1

这是答案！

import sys
from PyQt5.QtWidgets import QApplication, QMainWindow, QLabel, QGridLayout, QWidget, QPushButton, QAction, QStatusBar, QToolBar, QTabWidget
from PyQt5.QtCore import QCoreApplication


class FenetrePrincipale(QMainWindow):
    def __init__(self):
        super().__init__()
        self.setWindowTitle("Liseuse de Bandes Dessinées")
        self.left = 10
        self.top = 10
        self.width = 900
        self.height = 850
        self.i = 0

        self.setGeometry(self.left, self.top, self.width, self.height)

        self.toolbar = QToolBar("Toolbar")
        self.layout = QGridLayout()
        self.setCentralWidget(QWidget(self))
        self.centralWidget().setLayout(self.layout)
        self.move(200, 0)
        self.addToolBar(self.toolbar)

        self.table_widget = MyTableWidget(self)

        self.open = QAction("test", self)
        self.open.triggered.connect(self.table_widget.Open)

        self.setStatusBar(QStatusBar())
        self.menuFichier = self.menuBar().addMenu("&File")
        self.menuFichier.addAction(self.open)

        self.widget = QWidget()
        self.widget.setLayout(self.layout)
        self.setCentralWidget(self.widget)

        self.setCentralWidget(self.table_widget)

        self.show()


class MyTableWidget(QWidget):
    def __init__(self, parent=None):
        super(QWidget, self).__init__(parent)
        self.layout = QGridLayout()
        self.i = {}  # your self.i is now a dict
        self.n = 0
        self.index = {}
        self.tab = {}

        # Initialize tab screen
        self.tabs = QTabWidget()
        self.tabs.setDocumentMode(True)
        self.tabs.setMovable(True)

        # Add tabs to widget
        self.layout.addWidget(self.tabs)
        self.setLayout(self.layout)

    def Open(self):
        n = str(self.n)
        self.i[n] = 0  # assign new key as you make a tab
        self.tab[n] = QWidget()  # differentiate the tabs so we can call it back later when adding label
        self.tab[n].objectName()
        self.tab[n].layout = QGridLayout()
        self.nextpagebutton = QPushButton(">", self)
        self.nextpagebutton.setObjectName('>{}'.format(self.n))  # Give a unique name
        self.nextpagebutton.setFixedSize(50, 780)
        self.tab[n].layout.addWidget(self.nextpagebutton, 0, 2)
        self.nextpagebutton.clicked.connect(self.readnext)

        self.prevpagebutton = QPushButton("<", self)
        self.prevpagebutton.setObjectName('<{}'.format(self.n))  # Give a unique name
        self.prevpagebutton.setFixedSize(50, 780)
        self.tab[n].layout.addWidget(self.prevpagebutton, 0, 0)
        self.prevpagebutton.clicked.connect(self.readprev)

        self.index[n] = self.tabs.addTab(self.tab[n], "Tab " + str(self.n))
        self.tab[n].setLayout(self.tab[n].layout)
        self.n = int(self.n) + 1
        print(self.i)

    def readnext(self):
        name = str(self.sender().objectName())  # get the button's name
        identifier = name[-1]
        self.i[identifier] += 1
        if self.i[identifier] == 1:
            self.label = QLabel("testtext")
            self.tab[identifier].layout.addWidget(self.label, 0, 1)
        print(self.i)

    def readprev(self):
        name = str(self.sender().objectName())  # get the button's name
        identifier = name[-1]
        self.i[identifier] -= 1
        if self.i[identifier] == 1:
            self.label = QLabel("testtext")
            self.tab[identifier].layout.addWidget(self.label, 0, 1)
        print(self.i)


app = QCoreApplication.instance()
if app is None:
    app = QApplication(sys.argv)

window = FenetrePrincipale()
window.show()

app.exec_()