进入全屏模式会隐藏任务栏中的图标，并且应用程序从后台运行

Question

当我让一个窗口进入全屏模式时，应用程序图标从任务栏中隐藏（在执行 alt-tab 之后）。它也没有出现在alt+tab 窗口中。它只显示了我打开的其他窗口。

当我检查任务管理器时，python 进程在background processes 类别下。我无法切换回窗口。

当我进入全屏模式时，如何阻止应用程序在后台运行？

我的代码：

import sys
from PyQt5.QtGui import QKeySequence
from PyQt5.QtWidgets import QApplication, QLabel, QMainWindow, QShortcut
from PyQt5.QtCore import Qt

# Subclass QMainWindow to customise your application's main window
class MainWindow(QMainWindow):

    def __init__(self, *args, **kwargs):
        super(MainWindow, self).__init__(*args, **kwargs)

        self.setWindowTitle("Hello fullscreen world")

        label = QLabel("Hello fullscreen world")

        # The `Qt` namespace has a lot of attributes to customise
        # widgets. See: http://doc.qt.io/qt-5/qt.html
        label.setAlignment(Qt.AlignCenter)

        # Set the central widget of the Window. Widget will expand
        # to take up all the space in the window by default.
        self.setCentralWidget(label)

        
        self.shortcut_close_window = QShortcut(QKeySequence('F11'), self)
        self.shortcut_close_window.activated.connect(self.goFullscreen)
    def goFullscreen(self):
        if self.isFullScreen():
            self.setWindowFlags(self._flags)
            self.showNormal()
        else:
            self._flags = self.windowFlags()
            self.setWindowFlags(Qt.WindowCloseButtonHint | Qt.WindowType_Mask)
            self.showFullScreen()


app = QApplication(sys.argv)

window = MainWindow()
window.show()

app.exec_()

注意：即使使用 ctrl+c 终止进程或关闭命令提示符也不起作用，只有任务管理器可以。

Answer 1

我不知道你为什么在goFullscreen() 函数中使用self.setWindowFlags。没必要。

def goFullscreen(self):
        if self.isFullScreen():
            #self.setWindowFlags(self._flags)
            self.showNormal()
        else:
            #self._flags = self.windowFlags()
            #self.setWindowFlags(Qt.WindowCloseButtonHint | Qt.WindowType_Mask)
            self.showFullScreen()

顺便说一句，原因是您使用了 Qt.WindowType_Mask 标志。

WindowType_Mask：用于提取窗口类型部分的掩码 窗口标志。

~Window Flags~

---

我不知道 Ubuntu 中有这么奇怪的错误。所以你所要做的就是编写你自己的 FullScreen 方法：

（我不使用ubuntu。所以不知道你会不会再遇到bug。）

import sys
from PyQt5.QtGui import QKeySequence
from PyQt5.QtWidgets import QApplication, QLabel, QMainWindow, QShortcut
from PyQt5.QtCore import Qt


# Subclass QMainWindow to customise your application's main window
class MainWindow(QMainWindow):
    isfullscreen = False
    def __init__(self, *args, **kwargs):
        super(MainWindow, self).__init__(*args, **kwargs)

        self.setWindowTitle("Hello fullscreen world")

        self._flags = self.windowFlags()
        self._geometry = ((self.screen().size().width() / 2) - (self.width() / 2),
                          (self.screen().size().height() / 2) - (self.height() / 2), 600, 400)

        self.setGeometry(*self._geometry)

        label = QLabel("Hello fullscreen world")


        # The `Qt` namespace has a lot of attributes to customise
        # widgets. See: http://doc.qt.io/qt-5/qt.html
        label.setAlignment(Qt.AlignCenter)

        # Set the central widget of the Window. Widget will expand
        # to take up all the space in the window by default.
        self.setCentralWidget(label)

        self.shortcut_close_window = QShortcut(QKeySequence('F11'), self)
        self.shortcut_close_window.activated.connect(self.goShowFullScreen)
        self._geometry = self.geometry()

    def goShowFullScreen(self):
        if not self.isfullscreen:
            self.setWindowFlags(Qt.WindowStaysOnTopHint | Qt.FramelessWindowHint)
            self.setGeometry(self.screen().geometry())
            self.show()
            self.isfullscreen = True
        else:
            self.setWindowFlags(self.windowFlags() & ~Qt.WindowStaysOnTopHint)
            self.setWindowFlags(self.windowFlags() & ~Qt.FramelessWindowHint)
            self.setGeometry(self._geometry)
            self.show()
            self.isfullscreen = False


app = QApplication(sys.argv)

window = MainWindow()
window.show()

app.exec_()