Context Menu - Activated by Right Clicking

The script shows how to create a context menu in a GTK3 app. Users can activate the menu by right-clicking an item in a treeview.

1. Define a treeview list with two columns.
2. For the treeview, call the handler self.RowClick_event when the event button-press-event is trigged by the user clicking either the left or right mouse button.
3. In the handler RowClick_event(self, widget, event=None), use event.button1 to detect a left-click (normal click) and event.button1 to detect a right-click (activating the context menu).
4. Define a context menu and attach it to the treeview by the following:
   self.ctxmenu.attach_to_widget(self.tview,None)
   Three menu items, namely Move up, Move down and Delete, are defined in the menu. The actual codes for these items are given in self.callback. A separator is also defined to separate the Delete option from others.
5. Define a confirmation dialog for the delete operation issued by the context menu.

Source Code

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#!/usr/bin/env python3 # -*- coding: utf-8 -*- import gi gi.require_version('Gtk', '3.0') from gi.repository import Gtk, Pango class Base: def __init__(self): self.win = Gtk.Window() self.win.set_title("Context Menu") self.win.set_default_size(width=320, height=450) self.win.set_border_width(4) self.win.connect("delete-event", self.WinDelete_event) # # vbox holding all controls mBox = Gtk.VBox(homogeneous=False, spacing=3) self.win.add(mBox) # # entry self.entry = Gtk.Entry() mBox.pack_start(self.entry,False,True,2) # # liststore, treeview, cellrenderer, # treeviewcolumn, scrolledwindow self.lstore = Gtk.ListStore(str, int) # add data mItems = (("Japan 日本",+8), ("Germany 德國",+1), ("Singapore 新加玻",+8), ("France 法國", +1), ("Mexico 墨西哥", -6), ("United Kingdom 英國", 0), ("South Africa 南非", +2)) for mi in mItems: self.lstore.append(mi) self.tview = Gtk.TreeView(model=self.lstore) self.tview.connect( "button-press-event", self.RowClick_event) # column 0 mcellrend = Gtk.CellRendererText() mFont = Pango.FontDescription('San 10') mcellrend.set_property('font-desc',mFont) # text = 0 means get data from [0] of the list store lstore mtvcol00 = Gtk.TreeViewColumn("Country", mcellrend, text=0) mtvcol00.set_min_width(200) mtvcol00.set_resizable(True) mtvcol00.set_sort_column_id(0) self.tview.append_column(mtvcol00) # column 1 mcellrend = Gtk.CellRendererText() mFont = Pango.FontDescription('Serif Bold 10') mcellrend.set_property('font-desc',mFont) mcellrend.set_property('xalign',0.9) # right aligned mtvcol01 = Gtk.TreeViewColumn("UTC", mcellrend, text=1) mtvcol01.set_alignment(0.9) # column header righted aligned mtvcol01.set_sort_column_id(1) self.tview.append_column(mtvcol01) # self.tview.set_headers_clickable(False) # make column 0 searchable, # press Ctrl-f to start searching self.tview.set_search_column(0) # mscwin = Gtk.ScrolledWindow() mscwin.set_policy(Gtk.PolicyType.NEVER, Gtk.PolicyType.AUTOMATIC) mscwin.set_shadow_type(Gtk.ShadowType.IN) mscwin.add(self.tview) mBox.pack_start(mscwin,True,True,2) # # context menu for right-click on treeview self.ctxmenu = Gtk.Menu() mMenuItem1 = Gtk.MenuItem(label="Move up") mMenuItem1.connect('activate', self.callback, "mvUp") mMenuItem2 = Gtk.MenuItem(label="Move down") mMenuItem2.connect('activate', self.callback, "mvDown") mSeparator = Gtk.SeparatorMenuItem() mMenuItem3 = Gtk.MenuItem(label="Delete") mMenuItem3.connect('activate', self.callback, "delItem") self.ctxmenu.add(mMenuItem1) self.ctxmenu.add(mMenuItem2) self.ctxmenu.add(mSeparator) self.ctxmenu.add(mMenuItem3) self.ctxmenu.show_all() self.ctxmenu.attach_to_widget(self.tview,None) # # button box and 2 buttons mH2Box = Gtk.HBox(homogeneous=True, spacing=3) mbuttons = ((Gtk.STOCK_EDIT, 'edit an item', 'edtItem'), (Gtk.STOCK_CLEAR, 'clear all items', 'clrItems')) for mb in mbuttons: mbut = Gtk.Button() mImg = Gtk.Image() mImg.set_from_icon_name(mb[0], Gtk.IconSize.BUTTON) mbut.set_image(mImg) mbut.set_tooltip_text(mb[1]) mbut.connect("clicked",self.callback, mb[2]) mH2Box.pack_start(mbut,True,True,1) mBox.pack_start(mH2Box,False,True,2) # # status bar self.stsBar = Gtk.Statusbar() mBox.pack_start(self.stsBar,False,True,2) # self.win.show_all() # Event Handlers # --------------------------------------------------------- # callback def callback(self, widget, data): if data == 'clrItems': self.lstore.clear() self.pushStatus("clrItems","The list is empty.") self.entry.set_text('') self.entry.grab_focus() return # get iter of the selected item mv = self.tview.get_selection().get_selected() mModel = mv[0] mIter = mv[1] if mIter == None: return elif data == 'edtItem': # edit an item in the list mItem = self.entry.get_text() mItem = mItem.strip() if mItem=='': return self.lstore.set_value(mIter,0,mItem) # change col 0 to mItem # make the newly added item being selected self.tview.get_selection().select_iter(mIter) # push message to status bar mStr = "Edit: " + mItem self.pushStatus("edtItem",mStr) self.entry.set_text('') elif data == 'delItem': # get item to be deleted mNextIter = None mName = mModel.get_value(mIter,0) mNextIter = self.lstore.iter_next(mIter) # get confirmation mdia = Gtk.MessageDialog( transient_for = self.win, message_type = Gtk.MessageType.QUESTION, buttons = Gtk.ButtonsType.YES_NO, text='Delete Item\n\n%s'%mName ) mdia.format_secondary_text( 'Do you want to continue?') mres = mdia.run() mdia.destroy() if mres != Gtk.ResponseType.YES: return True # cancel quit # delete an item from the list self.lstore.remove(mIter) # remove iter from list mStr = "Del: " + mName self.pushStatus("delItem",mStr) if mNextIter != None: # highlight the next item in the list self.tview.get_selection().select_iter(mNextIter) else: # highlight the last item mLast = len(self.lstore) if mLast > 0: mLast = mLast - 1 self.tview.get_selection().select_path(mLast) else: # the list is cleared self.pushStatus("delItem","The list is empty.") self.entry.set_text('') self.entry.grab_focus() elif data == 'mvUp': mPrevIter = self.lstore.iter_previous(mIter) if mPrevIter == None: return mPrevName = mModel.get_value(mPrevIter,0) mPrevPrice = mModel.get_value(mPrevIter,1) mName = mModel.get_value(mIter,0) mPrice = mModel.get_value(mIter,1) self.lstore.set_value(mPrevIter,0,mName) self.lstore.set_value(mPrevIter,1,mPrice) self.lstore.set_value(mIter,0,mPrevName) self.lstore.set_value(mIter,1,mPrevPrice) mIdx = self.lstore.get_path(mPrevIter)[0] self.tview.set_cursor(mIdx) elif data == 'mvDown': mNextIter = self.lstore.iter_next(mIter) if mNextIter == None: return mNextName = mModel.get_value(mNextIter,0) mNextPrice = mModel.get_value(mNextIter,1) mName = mModel.get_value(mIter,0) mPrice = mModel.get_value(mIter,1) self.lstore.set_value(mNextIter,0,mName) self.lstore.set_value(mNextIter,1,mPrice) self.lstore.set_value(mIter,0,mNextName) self.lstore.set_value(mIter,1,mNextPrice) mIdx = self.lstore.get_path(mNextIter)[0] self.tview.set_cursor(mIdx) # Delete event def WinDelete_event(self, event, data=None): Gtk.main_quit() return False # row click or row change event in list def RowClick_event(self, widget, event=None): mtreepath = widget.get_path_at_pos(int(event.x), int(event.y)) if mtreepath != None: mIter = self.lstore.get_iter(mtreepath[0]) mName = self.lstore.get_value(mIter,0) # get column 0 mIdx = self.lstore.get_path(mIter)[0] # get index in list self.entry.set_text(mName) self.entry.grab_focus() if event.button==1: # normal click mStr = 'Click: ' elif event.button==3: # right click mStr = 'Context menu click: ' self.ctxmenu.popup(None,None,None,None,event.button,event.time) else: mStr = 'Middle click: ' mStr += str(mIdx) + ' Tag: ' + mName self.pushStatus("clickTag",mStr) # push message to status bar def pushStatus(self, pCtxt, pMsg): mctxid = self.stsBar.get_context_id(pCtxt) self.stsBar.push(mctxid, pMsg) def main(): Gtk.main() if __name__ == "__main__": base = Base() main()