class MainWindow(QtGui.QMainWindow):
    def __init__(self):
        # ...
        
        # Creating tabs and using tab widget as a Central widget
        self.tabs = QtGui.QTabWidget()
        self.tabs.TabShape(QtGui.QTabWidget.Rounded)
        self.tabs.addTab(BasicMode(), "Basic") # index = 0
        self.tabs.addTab(BulbMode(), "Bulb") # index = 1
        self.tabs.addTab(TimedMode(), "Timed") # index = 2
        self.tabs.addTab(ViewerMode(), "Viewer") # index = 3
        self.tabs.addTab(SystemPage(), "System") # index = 4
        self.tabHandler("startup")
        
        self.setCentralWidget(self.tabs)

    def tabHandler(self, data):
        print "Start managing tabs"
        
        if data == "startup":
            print "Managing state: StartUp"
            if USEFULLSCREEN != True:
                print "State: No Fullscreen \n   Action: Removing SystemTab"
                self.tabs.removeTab(4)
            if CURRENT_REMOTETYPE != "Olympus_RM-1":
                print "State: No olympus \n   Action: Removing ViewerTab"
                self.tabs.removeTab(3)
                
        if data == "settings":
            print "Managing state: SettingsChange"
            if CURRENT_REMOTETYPE != "Olympus_RM-1":
                print "State: No Olympus\n   Action: removing ViewerTab"
                self.tabs.removeTab(3)
            if CURRENT_REMOTETYPE == "Olympus_RM-1" and USEFULLSCREEN == True:
                print "State: is Olympus, is Fullscreen \n   Action: removing SystemTab, adding ViewerTab, adding SystemTab"
                self.tabs.removeTab(4)
                self.tabs.addTab(ViewerMode(), "Viewer")
                self.tabs.addTab(SystemPage(), "System")
            elif CURRENT_REMOTETYPE == "Olympus_RM-1" and USEFULLSCREEN != True:
                print "State: is Olympus, no Fullscreen \n   Action: adding ViewerTab"
                self.tabs.addTab(ViewerMode(), "Viewer")
        
        self.tabs.update()
        print "Managing tabs stopped!"
# ...

class SettingsDialog(QtGui.QDialog):
    def setSettings(self):
        # ...
        MainWindow().tabHandler("settings")
        settings.sync()

        self.accept()