How to use the leo.core.leoGlobals.doHook function in leo

def onIconBoxRightClick(self, event, p=None):
        """Handle a right click in any outline widget."""
        if self.busy:
            return
        c = self.c
        g.doHook("iconrclick1", c=c, p=p, event=event)
        g.doHook("iconrclick2", c=c, p=p, event=event)
        c.outerUpdate()
    #@+node:ekr.20110605121601.17894: *5* qtree.onIconBoxDoubleClick

def OnBodyClick (self,event=None):

        try:
            c = self.c ; p = c.currentPosition()
            if not g.doHook("bodyclick1",c=c,p=p,v=p,event=event):
                self.OnActivateBody(event=event)
                c.k.showStateAndMode(w=c.frame.body.bodyCtrl)
            g.doHook("bodyclick2",c=c,p=p,v=p,event=event)
        except:
            g.es_event_exception("bodyclick")

def drawText(self,p,x,y):

        """draw text for position p at nominal coordinates x,y."""

        assert(p)

        c = self.c
        x += self.text_indent

        data = g.doHook("draw-outline-text-box",tree=self,c=c,p=p,v=p,x=x,y=y)
        if data is not None: return data

        self.newText(p,x,y+self.lineyoffset)

        self.configureTextState(p)

        return self.line_height
    #@-node:ekr.20080112145409.360:drawText

def handleSpecialMenus(self, name, parentName, alt_name=None, table=None):
        """
        Handle a special menu if name is the name of a special menu.
        return True if this method handles the menu.
        """
        c = self.c
        if table is None: table = []
        name2 = name.replace('&', '').replace(' ', '').lower()
        if name2 == 'plugins':
            # Create the plugins menu using a hook.
            g.doHook("create-optional-menus", c=c, menu_name=name)
            return True
        if name2.startswith('recentfiles'):
            # Just create the menu.
            # createRecentFilesMenuItems will create the contents later.
            g.app.recentFilesManager.recentFilesMenuName = alt_name or name
                #848
            self.createNewMenu(alt_name or name, parentName)
            return True
        if name2 == 'help' and g.isMac:
            helpMenu = self.getMacHelpMenu(table)
            return helpMenu is not None
        return False
    #@+node:ekr.20031218072017.3780: *4* LeoMenu.hasSelection

def onDrag(self,event):

        g.trace()
        return ###

        c = self.c ; p = self.drag_p
        if not event: return

        c.setLog()

        if not self.dragging:
            if not g.doHook("drag1",c=c,p=p,v=p,event=event):
                self.startDrag(event)
            g.doHook("drag2",c=c,p=p,v=p,event=event)

        if not g.doHook("dragging1",c=c,p=p,v=p,event=event):
            self.onContinueDrag(event)
        g.doHook("dragging2",c=c,p=p,v=p,event=event)
    #@-node:ekr.20080112145409.395:onDrag

def OnBodyClick (self,event=None):

        try:
            c = self.c ; p = c.currentPosition()
            if not g.doHook("bodyclick1",c=c,p=p,v=p,event=event):
                self.OnActivateBody(event=event)
            g.doHook("bodyclick2",c=c,p=p,v=p,event=event)
        except:
            g.es_event_exception("bodyclick")

def drawNode(self,p,x,y):

        c = self.c

        # g.trace(x,y,p,id(self.canvas))

        data = g.doHook("draw-outline-node",tree=self,c=c,p=p,v=p,x=x,y=y)
        if data is not None: return data

        if 1:
            self.lineyoffset = 0
        else:
            if hasattr(p.v.t,"unknownAttributes"):
                self.lineyoffset = p.v.t.unknownAttributes.get("lineYOffset",0)
            else:
                self.lineyoffset = 0

        # Draw the horizontal line.
        self.drawLine(p,
            x,y+7+self.lineyoffset,
            x+self.box_width,y+7+self.lineyoffset)

        if self.inVisibleArea(y):

"""Handle right-clicks in the outline.

        This is *not* an event handler: it is called from other event handlers."""

        # Note: "headrclick" hooks handled by vnode callback routine.

        if event != None:
            c = self.c
            c.setLog()

            if not g.doHook("create-popup-menu",c=c,p=p,v=p,event=event):
                self.createPopupMenu(event)
            if not g.doHook("enable-popup-menu-items",c=c,p=p,v=p,event=event):
                self.enablePopupMenuItems(p,event)
            if not g.doHook("show-popup-menu",c=c,p=p,v=p,event=event):
                self.showPopupMenu(event)

        return "break"
    #@+node:ekr.20080112145409.410:OnPopupFocusLost

def on_idle(self):
        """Call all idle-time hooks."""
        if g.app.idle_time_hooks_enabled:
            for frame in g.app.windowList:
                c = frame.c
                # Do NOT compute c.currentPosition.
                # This would be a MAJOR leak of positions.
                g.doHook("idle", c=c)
    #@+node:ekr.20100908125007.6017: *4* plugins.doHandlersForTag & helper

c.setLog()

        if p and not g.doHook("boxclick1",c=c,p=p,v=p,event=event):
            c.endEditing()
            if p == p1 or self.initialClickExpandsOrContractsNode:
                if p.isExpanded(): p.contract()
                else:              p.expand()
            self.select(p)
            if c.frame.findPanel:
                c.frame.findPanel.handleUserClick(p)
            if self.stayInTree:
                c.treeWantsFocus()
            else:
                c.bodyWantsFocus()
        g.doHook("boxclick2",c=c,p=p,v=p,event=event)
        c.redraw()
    #@-node:ekr.20080112145409.387:onClickBoxClick