How to use the silx.gui.qt.QVBoxLayout function in silx

def __init__(self, parent=None):
        """Constructor

        :param parent: Parent of the widget
        """
        super(NumpyAxesSelector, self).__init__(parent)

        self.__data = None
        self.__selectedData = None
        self.__axis = []
        self.__axisNames = []
        self.__customAxisNames = set([])
        self.__namedAxesVisibility = True
        layout = qt.QVBoxLayout(self)
        layout.setContentsMargins(0, 0, 0, 0)
        layout.setSizeConstraint(qt.QLayout.SetMinAndMaxSize)
        self.setLayout(layout)

self.__dialogState = None
        self.__treeview = silx.gui.hdf5.Hdf5TreeView(self)
        """Silx HDF5 TreeView"""

        self.__dataViewer = DataViewerFrame(self)
        vSpliter = qt.QSplitter(qt.Qt.Vertical)
        vSpliter.addWidget(self.__dataViewer)
        vSpliter.setSizes([10, 0])

        spliter = qt.QSplitter(self)
        spliter.addWidget(self.__treeview)
        spliter.addWidget(vSpliter)
        spliter.setStretchFactor(1, 1)

        main_panel = qt.QWidget(self)
        layout = qt.QVBoxLayout()
        layout.addWidget(spliter)
        layout.setStretchFactor(spliter, 1)
        main_panel.setLayout(layout)

        self.setCentralWidget(main_panel)

        model = self.__treeview.selectionModel()
        model.selectionChanged.connect(self.displayData)
        self.__treeview.addContextMenuCallback(self.closeAndSyncCustomContextMenu)

        treeModel = self.__treeview.findHdf5TreeModel()
        columns = list(treeModel.COLUMN_IDS)
        columns.remove(treeModel.DESCRIPTION_COLUMN)
        columns.remove(treeModel.NODE_COLUMN)
        self.__treeview.header().setSections(columns)

dataLayout.addWidget(dummyCombo2)
        dataSelection.setLayout(dataLayout)

        self.__splitter = qt.QSplitter(self)
        self.__splitter.setContentsMargins(0, 0, 0, 0)
        self.__splitter.addWidget(sideBarWidget)
        self.__splitter.addWidget(datasetSelection)
        self.__splitter.addWidget(dataSelection)
        self.__splitter.setStretchFactor(1, 10)

        bottomLayout = qt.QHBoxLayout()
        bottomLayout.setContentsMargins(0, 0, 0, 0)
        bottomLayout.addWidget(self.__pathEdit)
        bottomLayout.addWidget(self.__buttons)

        layout = qt.QVBoxLayout(self)
        layout.addWidget(self.__splitter)
        layout.addLayout(bottomLayout)

        self.setLayout(layout)
        self.updateGeometry()

def __init__(self, *args, **kwargs):
        qt.QMainWindow.__init__(self, *args, **kwargs)

        widget = qt.QWidget(self)
        self.iconPanel = self.createIconPanel(widget)
        self.sizePanel = self.createSizePanel(widget)

        layout = qt.QVBoxLayout()
        widget.setLayout(layout)
        # layout.setSizeConstraint(qt.QLayout.SetMinAndMaxSize)
        layout.addWidget(self.sizePanel)
        layout.addWidget(self.iconPanel)
        layout.addStretch()
        self.setCentralWidget(widget)

def __init__(self, parent=None, modal=False, nohelp=True, nodefaults=True):
        """

        :param parent: parent widget
        :param modal: If ``True``, make dialog modal (block input to other
            visible windows). Default is ``False``.
        :param nohelp: If ``True`` (default), don't add *help* button
        :param nodefaults: If ``True`` (default), don't add *Defaults* button
        """
        qt.QDialog.__init__(self, parent)
        self.setWindowTitle(str("TabSheets"))
        self.setModal(modal)

        tabsheetslayout = qt.QVBoxLayout(self)
        tabsheetslayout.setContentsMargins(11, 11, 11, 11)
        tabsheetslayout.setSpacing(6)

        self.tabWidget = qt.QTabWidget(self)

        self.Widget8 = qt.QWidget(self.tabWidget)
        self.Widget9 = qt.QWidget(self.tabWidget)
        self.tabWidget.addTab(self.Widget8, str("Tab"))
        self.tabWidget.addTab(self.Widget9, str("Tab"))

        tabsheetslayout.addWidget(self.tabWidget)

        layout2 = qt.QHBoxLayout(None)
        layout2.setContentsMargins(0, 0, 0, 0)
        layout2.setSpacing(6)

def __init__(self, parent=None):
        qt.QDialog.__init__(self, parent)
        self.setWindowTitle("Strip and Snip Configuration Window")
        self.mainLayout = qt.QVBoxLayout(self)
        self.mainLayout.setContentsMargins(0, 0, 0, 0)
        self.mainLayout.setSpacing(2)
        self.parametersWidget = BackgroundWidget(self)
        self.mainLayout.addWidget(self.parametersWidget)
        hbox = qt.QWidget(self)
        hboxLayout = qt.QHBoxLayout(hbox)
        hboxLayout.setContentsMargins(0, 0, 0, 0)
        hboxLayout.setSpacing(2)
        self.okButton = qt.QPushButton(hbox)
        self.okButton.setText("OK")
        self.okButton.setAutoDefault(False)
        self.dismissButton = qt.QPushButton(hbox)
        self.dismissButton.setText("Cancel")
        self.dismissButton.setAutoDefault(False)
        hboxLayout.addWidget(HorizontalSpacer(hbox))
        hboxLayout.addWidget(self.okButton)

def _initGui(self):
        qt.loadUi(pyFAI.utils.get_ui_file("calibration-peakpicking.ui"), self)
        icon = silx.gui.icons.getQIcon("pyfai:gui/icons/task-identify-rings")
        self.setWindowIcon(icon)

        self.initNextStep()

        # Insert the plot on the layout
        holder = self._plotHolder
        self.__extractionThread = None
        self.__plot = _PeakPickingPlot(parent=holder)
        self.__plot.setObjectName("plot-picking")
        holderLayout = qt.QVBoxLayout(holder)
        holderLayout.setContentsMargins(1, 1, 1, 1)
        holderLayout.addWidget(self.__plot)

        # Insert the peak view on the layout
        holder = self._peakSelectionDummy.parent()
        self.__peakSelectionView = _PeakSelectionTableView(holder)
        holderLayout = holder.layout()
        holderLayout.replaceWidget(self._peakSelectionDummy, self.__peakSelectionView)

        self.__undoStack = qt.QUndoStack(self)

        layout = qt.QVBoxLayout()
        layout.setContentsMargins(0, 0, 0, 0)
        self._ringToolBarHolder.setLayout(layout)
        toolBar = self.__createMainRingToolBar()
        layout.addWidget(toolBar)

def createIconPanel(self, parent):
        panel = qt.QWidget(parent)
        layout = qt.QVBoxLayout()
        panel.setLayout(layout)

        self.tools = []

        # wait icon
        icon = silx.gui.icons.getWaitIcon()
        tool = AnimatedToolButton(panel)
        tool.setIcon(icon)
        tool.setText("getWaitIcon")
        tool.setToolButtonStyle(qt.Qt.ToolButtonTextBesideIcon)
        self.tools.append(tool)

        icon = silx.gui.icons.getAnimatedIcon("process-working")
        tool = AnimatedToolButton(panel)
        tool.setIcon(icon)
        tool.setText("getAnimatedIcon")

def _initOtherToolsGroupBox(self):
        layout = qt.QVBoxLayout()

        self.maskNanBtn = qt.QPushButton('Mask not finite values')
        self.maskNanBtn.setToolTip('Mask Not a Number and infinite values')
        self.maskNanBtn.clicked.connect(self._maskNotFiniteBtnClicked)
        layout.addWidget(self.maskNanBtn)

        self.otherToolGroup = qt.QGroupBox('Other tools')
        self.otherToolGroup.setLayout(layout)
        return self.otherToolGroup

def __createLayout(self):
        layout = qt.QVBoxLayout(self)
        layout.setContentsMargins(24, 15, 24, 20)
        layout.setSpacing(8)

        self.__label = qt.QLabel(self)
        self.__label.setWordWrap(True)
        flags = self.__label.textInteractionFlags()
        flags = flags | qt.Qt.TextSelectableByKeyboard
        flags = flags | qt.Qt.TextSelectableByMouse
        self.__label.setTextInteractionFlags(flags)
        self.__label.setOpenExternalLinks(True)
        self.__label.setSizePolicy(qt.QSizePolicy.Minimum, qt.QSizePolicy.Preferred)

        licenseButton = qt.QPushButton(self)
        licenseButton.setText("License...")
        licenseButton.clicked.connect(self.__displayLicense)
        licenseButton.setAutoDefault(False)