[gparted] Work around Gtkmm3 issue where menu accelerators are not shown (#7)

[Mike Fleetwood <mfleetwo src gnome org>]

commit 392bbba534fa32b4e48c7bb445400e226107c49b
Author: Luca Bacci <luca bacci982 gmail com>
Date:   Wed Nov 21 15:28:14 2018 +0100

    Work around Gtkmm3 issue where menu accelerators are not shown (#7)
    
    There is a bug in Gtkmm3 when setting accelerator keys on a
    Gtk::MenuItem, the accelerator keys work but are not displayed when the
    menu is drawn.  This happens for Gtk::MenuItems, including derived
    objects, that are constructed with a non-default constructor.
    
    All non-default constructors of Gtk::MenuItem, and subclasses, work by
    creating themselves a Gtk::AccelLabel and packing it inside the menu
    item.  But in Gtk3 GtkMenuItem are created with a GtkAccelLabel already
    packed in as a child and that accel label should be used instead.
    
    To workaround the issue we only use the default constructor for
    Gtk::MenuItem and subclasses.  This is easy to do because we only have
    to change the wrappers in MenuHelpers.cc.
    
    This bug affects Gtkmm version 3.0.0 to 3.22.2 and was fixed in
    Gtkmm 3.22.3.
    
     * Gtkmm 3.0.0 was released in April 2011
     * Gtkmm 3.22.3 was released in November 2018
    
    References:
    
    [1] Bug Report on the Gtkmm mailing list
        https://mail.gnome.org/archives/gtkmm-list/2018-February/msg00006.html
    
    [2] Commit - Gtk::MenuItem: Fix add_accel_label()
        https://gitlab.gnome.org/GNOME/gtkmm/commit/e5c8c2df67d0d7ec255055984e8f07d0f0fa0862
    
    Closes #7 - Port to Gtk3

 src/MenuHelpers.cc | 64 ++++++++++++++++++++++++++++++++++++++++++++----------
 1 file changed, 53 insertions(+), 11 deletions(-)
---
diff --git a/src/MenuHelpers.cc b/src/MenuHelpers.cc
index d71f8a92..feec5fed 100644
--- a/src/MenuHelpers.cc
+++ b/src/MenuHelpers.cc
@@ -19,6 +19,7 @@
 #include <gtkmm/imagemenuitem.h>
 #include <gtkmm/checkmenuitem.h>
 #include <gtkmm/separatormenuitem.h>
+#include <gtkmm/stock.h>
 
 namespace GParted
 {
@@ -29,34 +30,43 @@ namespace Menu_Helpers
 MenuElem::MenuElem(const Glib::ustring& label,
                    const Gtk::AccelKey& key,
                    const CallSlot& slot)
- : Gtk::MenuItem(label, true)
+ : Gtk::MenuItem()
 {
        if (slot)
                signal_activate().connect(slot);
 
        set_accel_key(key);
 
+       set_label(label);
+       set_use_underline(true);
+
        show_all();
 }
 
 
 MenuElem::MenuElem(const Glib::ustring & label,
                    const CallSlot & slot)
- : Gtk::MenuItem(label, true)
+ : Gtk::MenuItem()
 {
        if (slot)
                signal_activate().connect(slot);
 
+       set_label(label);
+       set_use_underline(true);
+
        show_all();
 }
 
 
 MenuElem::MenuElem(const Glib::ustring & label,
                    Gtk::Menu & submenu)
- : Gtk::MenuItem(label, true)
+ : Gtk::MenuItem()
 {
        set_submenu(submenu);
 
+       set_label(label);
+       set_use_underline(true);
+
        show_all();
 }
 
@@ -65,13 +75,17 @@ ImageMenuElem::ImageMenuElem(const Glib::ustring& label,
                              const Gtk::AccelKey& key,
                              Gtk::Widget& image_widget,
                              const CallSlot& slot)
- : ImageMenuItem(image_widget, label, true)
+ : ImageMenuItem()
 {
        if (slot)
                signal_activate().connect(slot);
 
        set_accel_key(key);
 
+       set_image(image_widget);
+       set_label(label);
+       set_use_underline(true);
+
        show_all();
 }
 
@@ -79,11 +93,15 @@ ImageMenuElem::ImageMenuElem(const Glib::ustring& label,
 ImageMenuElem::ImageMenuElem(const Glib::ustring& label,
                              Gtk::Widget& image_widget,
                              const CallSlot& slot)
- : ImageMenuItem(image_widget, label, true)
+ : ImageMenuItem()
 {
        if (slot)
                signal_activate().connect(slot);
 
+       set_image(image_widget);
+       set_label(label);
+       set_use_underline(true);
+
        show_all();
 }
 
@@ -91,10 +109,14 @@ ImageMenuElem::ImageMenuElem(const Glib::ustring& label,
 ImageMenuElem::ImageMenuElem(const Glib::ustring& label,
                              Gtk::Widget& image_widget,
                              Gtk::Menu& submenu)
- : ImageMenuItem(image_widget, label, true)
+ : ImageMenuItem()
 {
        set_submenu(submenu);
 
+       set_image(image_widget);
+       set_label(label);
+       set_use_underline(true);
+
        show_all();
 }
 
@@ -109,34 +131,48 @@ SeparatorElem::SeparatorElem()
 StockMenuElem::StockMenuElem(const Gtk::StockID& stock_id,
                              const Gtk::AccelKey& key,
                              const CallSlot& slot)
- : Gtk::ImageMenuItem(stock_id)
+ : Gtk::ImageMenuItem()
 {
        if (slot)
                signal_activate().connect(slot);
 
        set_accel_key(key);
 
+       set_use_stock();
+       set_label(stock_id.get_string());
+
        show_all();
 }
 
 
 StockMenuElem::StockMenuElem(const Gtk::StockID& stock_id,
                              const CallSlot& slot)
- : Gtk::ImageMenuItem(stock_id)
+ : Gtk::ImageMenuItem()
 {
        if (slot)
                signal_activate().connect(slot);
 
+       Gtk::StockItem stock;
+       if (Gtk::Stock::lookup(stock_id, stock))
+               set_accel_key(Gtk::AccelKey(stock.get_keyval(),
+                                           stock.get_modifier()));
+
+       set_use_stock();
+       set_label(stock_id.get_string());
+
        show_all();
 }
 
 
 StockMenuElem::StockMenuElem(const Gtk::StockID& stock_id,
                              Gtk::Menu& submenu)
- : Gtk::ImageMenuItem(stock_id)
+ : Gtk::ImageMenuItem()
 {
        set_submenu(submenu);
 
+       set_use_stock();
+       set_label(stock_id.get_string());
+
        show_all();
 }
 
@@ -144,24 +180,30 @@ StockMenuElem::StockMenuElem(const Gtk::StockID& stock_id,
 CheckMenuElem::CheckMenuElem(const Glib::ustring& label,
                              const Gtk::AccelKey& key,
                              const CallSlot& slot)
- : Gtk::CheckMenuItem(label, true)
+ : Gtk::CheckMenuItem()
 {
        if (slot)
                signal_activate().connect(slot);
 
        set_accel_key(key);
 
+       set_label(label);
+       set_use_underline(true);
+
        show_all();
 }
 
 
 CheckMenuElem::CheckMenuElem(const Glib::ustring& label,
                              const CallSlot& slot)
- : Gtk::CheckMenuItem(label, true)
+ : Gtk::CheckMenuItem()
 {
        if (slot)
                signal_activate().connect(slot);
 
+       set_label(label);
+       set_use_underline(true);
+
        show_all();
 }