QFileDialog在添加到QHBoxLayou时打开新窗口

Question

我的问题是，当我将QFileDialog添加到QVBoxLayout时，它会在新窗口中打开。下面是产生我的问题的代码。在

from PyQt5.QtWidgets import QVBoxLayout, QFileDialog, QPushButton, QWidget


class MainWindow(QtWidgets.QWidget):
    def __init__(self):
       super(MainWindow, self).__init__()
       self.setWindowTitle("My own MainWindow")

       self.fileDialog = QFileDialog()

       self.confirmAction = QPushButton("Press me", self)

       mainLayout = QVBoxLayout()

       mainLayout.addWidget(self.fileDialog)
       mainLayout.addWidget(self.confirmAction)
       self.setLayout(mainLayout)

Answer 1

我自己也一直在调查这个问题，对“只使用非本机对话”一点不满意。我一直在KDE平台文件对话框实现中进行黑客攻击，并且已经（卡住）了我想要的东西。在

我发现的唯一附加点是在对话框实际显示之前；在此之前，似乎没有办法知道实际的父窗口小部件。但我们可以：

• 找到父级QWidget（从父级QWindow）
• 从中，获得（第一个）（用户端）QFileDialog实例
• 如果父QWidget有一个布局，用我们自己的对话框替换找到的QFileDialog实例
• 保存原始用户端QFileDialog实例
• 在dtor中，恢复布局中的原始QFD，或对其调用deleteLater（）（并将其设置为NULL，以防操作导致对dtor的递归调用）。在

故障： -对话框可能以2组“确定/取消”等按钮结束 -如果不是，这些按钮实际上可能只关闭嵌入的QFD，而不是封闭的对话框（见上面链接的python示例） -调整大小有效，但saveSize/restoreSize机制不起作用 -所有信号都没有正确连接（Scribus打开文件对话框中的预览对选择文件没有反应）。不过，打开文件确实管用。在

此BKO票据的完整补丁： https://bugs.kde.org/show_bug.cgi?id=404833#c15

显然，这只对黑客和可以发布自己的平台主题插件（KDE平台文件对话框的来源）的软件有用。幸运的是，这些插件往往相对较小。在

Answer 2

根据docs：

Window flags are a combination of a type (e.g. Qt::Dialog) and zero or more hints to the window system (e.g. Qt::FramelessWindowHint).

If the widget had type Qt::Widget or Qt::SubWindow and becomes a window (Qt::Window, Qt::Dialog, etc.), it is put at position (0, 0) on the desktop. If the widget is a window and becomes a Qt::Widget or Qt::SubWindow, it is put at position (0, 0) relative to its parent widget.

因此，这些标志用于改变小部件的行为，例如将其转换为窗口、对话框、工具提示等。在

在docs中给出了以下列表：

Qt::Widget: This is the default type for QWidget. Widgets of this type are child widgets if they have a parent, and independent windows if they have no parent. See also Qt::Window and Qt::SubWindow.

Qt::Window: Indicates that the widget is a window, usually with a window system frame and a title bar, irrespective of whether the widget has a parent or not. Note that it is not possible to unset this flag if the widget does not have a parent.

Qt::Dialog :Window Indicates that the widget is a window that should be decorated as a dialog (i.e., typically no maximize or minimize buttons in the title bar). This is the default type for QDialog. If you want to use it as a modal dialog, it should be launched from another window, or have a parent and used with the QWidget::windowModality property. If you make it modal, the dialog will prevent other top-level windows in the application from getting any input. We refer to a top-level window that has a parent as a secondary window.

Qt::Sheet: Window Indicates that the window is a Macintosh sheet. Since using a sheet implies window modality, the recommended way is to use QWidget::setWindowModality(), or QDialog::open(), instead.

Qt::Drawer: Window Indicates that the widget is a Macintosh drawer.

Qt::Popup : Window Indicates that the widget is a pop-up top-level window, i.e. that it is modal, but has a window system frame appropriate for pop-up menus.

Qt::Tool: Window Indicates that the widget is a tool window. A tool window is often a small window with a smaller than usual title bar and decoration, typically used for collections of tool buttons. If there is a parent, the tool window will always be kept on top of it. If there isn't a parent, you may consider using Qt::WindowStaysOnTopHint as well. If the window system supports it, a tool window can be decorated with a somewhat lighter frame. It can also be combined with Qt::FramelessWindowHint.

On Mac OS X, tool windows correspond to the Floating class of windows. This means that the window lives on a level above normal windows; it impossible to put a normal window on top of it. By default, tool windows will disappear when the application is inactive. This can be controlled by the Qt::WA_MacAlwaysShowToolWindow attribute.

Qt::ToolTip:Window Indicates that the widget is a tooltip. This is used internally to implement tooltips.

Qt::SplashScreen: Window Indicates that the window is a splash screen. This is the default type for QSplashScreen.

Qt::Desktop:Window Indicates that this widget is the desktop. This is the type for QDesktopWidget.

Qt::SubWindow: Indicates that this widget is a sub-window, such as a QMdiSubWindow widget.

在您的例子中，我们必须将Qt::Dialog的行为更改为Qt::Widget，在下面的代码中，我展示了执行此操作的代码：

class MainWindow(QWidget):
    def __init__(self):
       super(MainWindow, self).__init__()
       self.setWindowTitle("My own MainWindow")

       self.fileDialog = QFileDialog(self)
       self.fileDialog.setOption(QFileDialog.DontUseNativeDialog)
       self.fileDialog.setWindowFlags(Qt.Widget)

       self.confirmAction = QPushButton("Press me", self)

       mainLayout = QVBoxLayout()

       mainLayout.addWidget(self.fileDialog)
       mainLayout.addWidget(self.confirmAction)
       self.setLayout(mainLayout)

截图：