How to use the leo.core.leoGlobals.app.gui function in leo

def init():

    # Equivalent functionality comes with contextmenu.py on qt ui.

    ok = Tk and g.app.gui.guiName() == 'tkinter'

    if ok:
        g.app.hasOpenWithMenu = True
        g.enableIdleTimeHook(idleTimeDelay=1000) # Check every second.
        g.registerHandler("idle", on_idle)
        g.registerHandler('menu2', create_open_with_menu)
        g.plugin_signon(__name__)

    return ok
#@+node:EKR.20040517075715.5: ** on_idle

def init():

    if g.app.unitTesting: # Not Ok for unit testing!
        return False

    if not gtk:
        return False

    if g.app.gui:
        return g.app.gui.guiName() == 'gtk'
    else:
        g.app.gui = leoGtkGui.gtkGui()
        # g.app.root = g.app.gui.createRootWindow()
        g.app.gui.finishCreate()
        g.plugin_signon(__name__)
        return True
#@-node:ekr.20080112150934.1:init

Prompt the user to save changes.
        Return True if the user vetos the quit or save operation.
        '''
        c = self.c
        # if g.app.gui.guiName() == 'curses':
            # g.trace('Saves disabled for curses gui')
            # return False
        theType = "quitting?" if g.app.quitting else "closing?"
        # See if we are in quick edit/save mode.
        root = c.rootPosition()
        quick_save = not c.mFileName and not root.next() and root.isAtEditNode()
        if quick_save:
            name = g.shortFileName(root.atEditNodeName())
        else:
            name = c.mFileName if c.mFileName else self.title
        answer = g.app.gui.runAskYesNoCancelDialog(c,
            title="Confirm",
            message='Save changes to %s before %s' % (
                g.splitLongFileName(name), theType))
        if answer == "cancel":
            return True # Veto.
        if answer == "no":
            return False # Don't save and don't veto.
        if not c.mFileName:
            root = c.rootPosition()
            if not root.next() and root.isAtEditNode():
                # There is only a single @edit node in the outline.
                # A hack to allow "quick edit" of non-Leo files.
                # See https://bugs.launchpad.net/leo-editor/+bug/381527
                # Write the @edit node if needed.
                if root.isDirty():
                    c.atFileCommands.writeOneAtEditNode(root,

theFile = lm.openLeoOrZipFile(fn)
        if theFile:
            message('reading settings in %s' % (fn))
        # Changing g.app.gui here is a major hack.  It is necessary.
        oldGui = g.app.gui
        g.app.gui = g.app.nullGui
        c = g.app.newCommander(fn)
        frame = c.frame
        frame.log.enable(False)
        g.app.lockLog()
        ok = c.fileCommands.openLeoFile(theFile,fn,
            readAtFileNodesFlag=False,silent=True)
                # closes theFile.
        g.app.unlockLog()
        c.openDirectory = frame.openDirectory = g.os_path_dirname(fn)
        g.app.gui = oldGui
        return ok and c or None
    #@+node:ekr.20120213081706.10382: *4* lm.readGlobalSettingsFiles

self.colorTags = [] # list of color names used as tags.
            self.enabled = False
            self.isVisible = False
            self.lastRow = self.lastCol = 0
            self.log = c.frame.log
            #if 'black' not in self.log.colorTags:
            #    self.log.colorTags.append("black")
            self.parentFrame = parentFrame
            self.statusFrame = Tk.Frame(parentFrame,bd=2)
            text = "line 0, col 0, fcol 0"
            width = len(text) + 4
            self.labelWidget = Tk.Label(self.statusFrame,text=text,width=width,anchor="w")
            self.labelWidget.pack(side="left",padx=1)

            bg = self.statusFrame.cget("background")
            self.textWidget = w = g.app.gui.bodyTextWidget(
                self.statusFrame,
                height=1,state="disabled",bg=bg,relief="groove",name='status-line')
            self.textWidget.pack(side="left",expand=1,fill="x")
            c.bind(w,"", self.onActivate)
            self.show()

            c.frame.statusFrame = self.statusFrame
            c.frame.statusLabel = self.labelWidget
            c.frame.statusText  = self.textWidget
        #@-node:ekr.20031218072017.3961:ctor

def init ():

    ok = Pmw and Tk

    if ok:
        if g.app.gui is None:
            g.app.createTkGui(__file__)
        ok = g.app.gui.guiName() == "tkinter"
        if ok:
            g.registerHandler('before-create-leo-frame',onCreate)
            g.plugin_signon(__name__)

    return ok
#@+node:ekr.20050301105220: ** onCreate

def replaceClipboardWith (self,s):

        # g.app.gui.win32clipboard is always None.
        wcb = g.app.gui.win32clipboard

        if wcb:
            try:
                wcb.OpenClipboard(0)
                wcb.EmptyClipboard()
                wcb.SetClipboardText(s)
                wcb.CloseClipboard()
            except:
                g.es_exception()
        else:
            self.root.clipboard_clear()
            self.root.clipboard_append(s)
    #@-node:ekr.20031218072017.845:replaceClipboardWith

def readOpmlCommand(self, event=None):
        '''Open a Leo window containing the contents of an .opml file.'''
        c = self.c
        fileName = g.app.gui.runOpenFileDialog(c,
            title="Read OPML",
            filetypes=[("OPML files", "*.opml"), ("All files", "*")],
            defaultextension=".opml")
        c.bringToFront()
        if fileName:
            self.readFile(fileName)
        else:
            c.bodyWantsFocus()
    #@+node:ekr.20060904103721.1: *3* oc.writeFile

def weave(self, event=None):
    """Simulate a literate-programming weave operation by writing the outline to a text file."""
    c = self
    filetypes = [("Text files", "*.txt"), ("All files", "*")]
    fileName = g.app.gui.runSaveFileDialog(c,
        initialfile="weave.txt",
        title="Weave",
        filetypes=filetypes,
        defaultextension=".txt")
    c.bringToFront()
    if fileName:
        g.setGlobalOpenDir(fileName)
        g.chdir(fileName)
        c.importCommands.weave(fileName)
#@+node:ekr.20031218072017.2838: ** Read/Write

def attachIconCallback(top=self.top):
                g.app.gui.attachLeoIcon(top)