How to use the pyqtgraph.Qt.QtGui.QWidget function in pyqtgraph

module=getattr(self.rp, "pid0")
                                 )
        # a IQ controller for "iq0" here
        self.iq_widget = IqWidget(name="iq0",
                                  rp=self.rp,
                                  parent=None,
                                  module=getattr(self.rp, "iq0")
                                  )
        # setup controller layout here
        self.control_widget_layout = QtGui.QVBoxLayout()
        self.control_widget_layout.addWidget(self.asg_widget)
        self.control_widget_layout.addWidget(self.scope_widget)
        self.control_widget_layout.addWidget(self.pid_widget)
        self.control_widget_layout.addWidget(self.iq_widget)
        #
        self.control_widget=QtGui.QWidget()
        self.control_widget.setLayout(self.control_widget_layout)
        #------------#
        # a scope for another rp
        '''
        self.another_scope_widget = ScopeWidget(name="another_SHG",
                                                rp=another_rp,
                                                parent=None,
                                                module=self.another_rp.scope
                                                )
        '''
        # set dock_widgets for the main windows
        self.dock_widgets = {}
        self.last_docked = None
        self.add_dock_widget(self.console_widget,'console')
        self.add_dock_widget(self.control_widget,'controller')
        #self.add_dock_widget(self.another_scope_widget, 'another')

self.verticalLayout_4.setObjectName(_fromUtf8("verticalLayout_4"))
        self.label_7 = QtGui.QLabel(self.groupBoxDis_2)
        self.label_7.setObjectName(_fromUtf8("label_7"))
        self.verticalLayout_4.addWidget(self.label_7)
        self.gridLayout_45.addWidget(self.groupBoxDis_2, 2, 3, 1, 1)
        self.stackedWidget_2 = QtGui.QStackedWidget(self.dockWidgetContents)
        self.stackedWidget_2.setObjectName(_fromUtf8("stackedWidget_2"))
        self.page1_2 = QtGui.QWidget()
        self.page1_2.setObjectName(_fromUtf8("page1_2"))
        self.gridLayout_35 = QtGui.QGridLayout(self.page1_2)
        self.gridLayout_35.setObjectName(_fromUtf8("gridLayout_35"))
        self.label_57 = QtGui.QLabel(self.page1_2)
        self.label_57.setObjectName(_fromUtf8("label_57"))
        self.gridLayout_35.addWidget(self.label_57, 0, 0, 1, 1)
        self.stackedWidget_2.addWidget(self.page1_2)
        self.page2_2 = QtGui.QWidget()
        self.page2_2.setObjectName(_fromUtf8("page2_2"))
        self.gridLayout_36 = QtGui.QGridLayout(self.page2_2)
        self.gridLayout_36.setObjectName(_fromUtf8("gridLayout_36"))
        self.label_58 = QtGui.QLabel(self.page2_2)
        self.label_58.setObjectName(_fromUtf8("label_58"))
        self.gridLayout_36.addWidget(self.label_58, 0, 0, 1, 1)
        self.stackedWidget_2.addWidget(self.page2_2)
        self.gridLayout_45.addWidget(self.stackedWidget_2, 5, 2, 1, 1)
        self.stackedWidgetDis_2 = QtGui.QStackedWidget(self.dockWidgetContents)
        self.stackedWidgetDis_2.setEnabled(False)
        self.stackedWidgetDis_2.setObjectName(_fromUtf8("stackedWidgetDis_2"))
        self.page1Dis_2 = QtGui.QWidget()
        self.page1Dis_2.setObjectName(_fromUtf8("page1Dis_2"))
        self.gridLayout_37 = QtGui.QGridLayout(self.page1Dis_2)
        self.gridLayout_37.setObjectName(_fromUtf8("gridLayout_37"))
        self.label_113 = QtGui.QLabel(self.page1Dis_2)

f.close()
        
        if keys is None:
            keys = np.unique(self.pd.objid.values)
        print 'N keys: ', len(keys)
        self.keys = keys
        self.key_index = -1
        self.key = None
        self.candidate = None
        self.candidates = None
        self.candidate_index = -1
        self.new_key = True
        
        ## create GUI
        self.app = QtGui.QApplication([])
        self.w = QtGui.QWidget()
        self.layout = QtGui.QGridLayout()
        self.w.setLayout(self.layout)
        
        next_btn = QtGui.QPushButton('next match')
        next_btn.pressed.connect(self.next_stitch)
        self.layout.addWidget(next_btn, 0, 0)
        
        save_btn = QtGui.QPushButton('save stitch')
        save_btn.pressed.connect(self.save_stitch)
        self.layout.addWidget(save_btn, 1, 0)
        
        reject_btn = QtGui.QPushButton('reject stitch')
        reject_btn.pressed.connect(self.reject_stitch)
        self.layout.addWidget(reject_btn, 2, 0)
        
        self.button = 'accepted'

d5 = Dock("Dock5", size=(100,100))
d6 = Dock("Dock6", size=(300,300))
area.addDock(d1, 'left')
area.addDock(d2, 'right')
area.addDock(d3, 'bottom')
area.addDock(d4, 'right')
area.addDock(d5, 'left', d1)
area.addDock(d6, 'top', d4)

area.moveDock(d6, 'above', d4)
d3.hideTitleBar()

print("===build complete====")

for d in [d1, d2, d3, d4, d5]:
    w = QtGui.QWidget()
    l = QtGui.QVBoxLayout()
    w.setLayout(l)
    btns = []
    for i in range(4):
        btns.append(QtGui.QPushButton("%s Button %d"%(d.name(), i)))
        l.addWidget(btns[-1])
    d.w = (w, l, btns)
    d.addWidget(w)



import pyqtgraph as pg
p = pg.PlotWidget()
d6.addWidget(p)

print("===widgets added===")

opts = self.param.opts
        if 'tip' in opts:
            w.setToolTip(opts['tip'])

        self.displayLabel = QtGui.QLabel()
        self.displayLabel.hide()

        self.defaultBtn = QtGui.QPushButton("")
        self.defaultBtn.hide()

        layout = QtGui.QHBoxLayout()
        layout.setContentsMargins(0, 0, 0, 0)
        layout.addWidget(w)
        layout.addWidget(self.displayLabel)
        layout.addWidget(self.defaultBtn)
        self.layoutWidget = QtGui.QWidget()
        self.layoutWidget.setLayout(layout)

        if w.sigChanged is not None:
            w.sigChanged.connect(self.widgetValueChanged)

        if hasattr(w, 'sigChanging'):
            w.sigChanging.connect(self.widgetValueChanging)

        ## update value shown in widget.
        if opts.get('value', None) is not None:
            self.valueChanged(self, opts['value'], force=True)
        else:
            ## no starting value was given; use whatever the widget has
            self.widgetValueChanged()

|list| |------------------|
        |----|<|                  |
        |data| |     graph2       |
        |list| |                  |
        ===========================
        """
        super(MainWindow, self).__init__()
        
        self.log_data_list = None
        self.log_file_name = None
        self.data_dict = None
        self.log_info_data = None
        self.log_params_data = None
        self.log_changed_params = []

        self.main_widget = QtGui.QWidget(self)
        self.mainlayout = QtGui.QHBoxLayout()
        self.main_widget.setLayout(self.mainlayout)
        
        # ToolBar
        self.toolbar = self.addToolBar('FileManager')
        self.basic_tool_group = QtGui.QActionGroup(self)
        ## load log file
        self.loadfile_action = QtGui.QAction(QtGui.QIcon(get_source_name('icons/open.gif')), 'Open log file', self)
        self.loadfile_action.setShortcut('Ctrl+O')
        self.loadfile_action.triggered.connect(self.callback_open_log_file)
        self.toolbar.addAction(self.loadfile_action)
        ## plot quadrotor in 3d graph
        self.show_quadrotor_3d = QtGui.QAction(QtGui.QIcon(get_source_name('icons/quadrotor.gif')), 'show 3d viewer', self)
        self.show_quadrotor_3d.setShortcut('Ctrl+Shift+Q')
        self.show_quadrotor_3d.triggered.connect(self.callback_show_quadrotor)
        self.toolbar.addAction(self.show_quadrotor_3d)

def initUIControls(self):
        self.uiConrolsWidget = QtGui.QWidget()
        buttonBarWidgetLayout = QtGui.QHBoxLayout(spacing=0)
        buttonBarWidgetLayout.setContentsMargins(0, 0, 0, 0)
        buttonBarWidgetLayout.setSpacing(0)
        self.uiConrolsWidget.setLayout(buttonBarWidgetLayout)
        
        def addButton(label, widget=None, function=None):
            button = QtGui.QPushButton(label)
            if function is None:
                button.clicked.connect(lambda: widget.setVisible(widget.isHidden()))
            else:
                button.clicked.connect(function)
            button.setStyleSheet('QPushButton {'
                                 'border-color: black;'
                                 'border-width: 5px;}')
            buttonBarWidgetLayout.addWidget(button)
            return button

def setItemWidget(self, item, col, wid):
        """
        Overrides QTreeWidget.setItemWidget such that widgets are added inside an invisible wrapper widget.
        This makes it possible to move the item in and out of the tree without its widgets being automatically deleted.
        """
        w = QtGui.QWidget()  ## foster parent / surrogate child widget
        l = QtGui.QVBoxLayout()
        l.setContentsMargins(0,0,0,0)
        w.setLayout(l)
        w.setSizePolicy(wid.sizePolicy())
        w.setMinimumHeight(wid.minimumHeight())
        w.setMinimumWidth(wid.minimumWidth())
        l.addWidget(wid)
        w.realChild = wid
        self.placeholders.append(w)
        QtGui.QTreeWidget.setItemWidget(self, item, col, w)

def setupUi(self, MainWindow):
        MainWindow.setObjectName(_fromUtf8("MainWindow"))
        MainWindow.resize(596, 569)
        self.centralwidget = QtGui.QWidget(MainWindow)
        self.centralwidget.setObjectName(_fromUtf8("centralwidget"))
        self.gridLayout_7 = QtGui.QGridLayout(self.centralwidget)
        self.gridLayout_7.setObjectName(_fromUtf8("gridLayout_7"))
        self.groupBox_2 = QtGui.QGroupBox(self.centralwidget)
        self.groupBox_2.setObjectName(_fromUtf8("groupBox_2"))
        self.gridLayout = QtGui.QGridLayout(self.groupBox_2)
        self.gridLayout.setObjectName(_fromUtf8("gridLayout"))
        self.tabWidget = QtGui.QTabWidget(self.groupBox_2)
        self.tabWidget.setObjectName(_fromUtf8("tabWidget"))
        self.tab = QtGui.QWidget()
        self.tab.setObjectName(_fromUtf8("tab"))
        self.gridLayout_4 = QtGui.QGridLayout(self.tab)
        self.gridLayout_4.setObjectName(_fromUtf8("gridLayout_4"))
        self.groupBox_3 = QtGui.QGroupBox(self.tab)
        self.groupBox_3.setObjectName(_fromUtf8("groupBox_3"))
        self.gridLayout_5 = QtGui.QGridLayout(self.groupBox_3)

self.gridTwoChButton = QtGui.QPushButton('Two-color grid 128px')
        self.gridTwoChButton.setCheckable(True)
        self.gridTwoChButton.setEnabled(False)
        self.gridTwoCh82Button = QtGui.QPushButton('Two-color grid 82px')
        self.gridTwoCh82Button.setCheckable(True)
        self.gridTwoCh82Button.setEnabled(False)
        self.crosshairButton = QtGui.QPushButton('Crosshair')
        self.crosshairButton.setCheckable(True)
        self.crosshairButton.setEnabled(False)

        self.flipperButton = QtGui.QPushButton('x1000')
        self.flipperButton.setStyleSheet("font-size:16px")
        self.flipperButton.setCheckable(True)
        self.flipperButton.clicked.connect(self.daq.toggleFlipper)

        self.viewCtrl = QtGui.QWidget()
        self.viewCtrlLayout = QtGui.QGridLayout(self.viewCtrl)
        self.viewCtrlLayout.addWidget(self.liveviewButton, 0, 0, 1, 4)
        self.viewCtrlLayout.addWidget(self.gridButton, 1, 0)
        self.viewCtrlLayout.addWidget(self.gridTwoChButton, 1, 1)
        self.viewCtrlLayout.addWidget(self.gridTwoCh82Button, 1, 2)
        self.viewCtrlLayout.addWidget(self.crosshairButton, 1, 3)
        self.viewCtrlLayout.addWidget(self.flipperButton, 2, 0, 1, 4)

        # Status bar info
        self.fpsBox = QtGui.QLabel('0 fps', self)
        self.statusBar().addPermanentWidget(self.fpsBox)
        self.tempStatus = QtGui.QLabel(self)
        self.statusBar().addPermanentWidget(self.tempStatus)
        self.temp = QtGui.QLabel(self)
        self.statusBar().addPermanentWidget(self.temp)
        self.cursorPos = QtGui.QLabel('0, 0', self)