[gtkmm-documentation] examples: Update calls to Gtk::Builder::get_widget()

[Kjell Ahlstedt <kjellahl src gnome org>]

commit 9bbeb11b7587cced0dc17a92b8791f39274299b1
Author: Kjell Ahlstedt <kjellahlstedt gmail com>
Date:   Wed May 22 09:24:14 2019 +0200

    examples: Update calls to Gtk::Builder::get_widget()
    
    and calls to get_widget_derived() and get_object().
    
    widget = get_widget<WidgetType>("name") instead of get_widget("name", widget).

 examples/book/buildapp/step2/exampleappwindow.cc   |  3 +--
 examples/book/buildapp/step3/exampleappwindow.cc   |  5 ++---
 examples/book/buildapp/step4/exampleapplication.cc |  3 +--
 examples/book/buildapp/step5/exampleapplication.cc |  3 +--
 examples/book/buildapp/step5/exampleappprefs.cc    |  7 +++----
 examples/book/buildapp/step5/exampleappwindow.cc   |  5 ++---
 examples/book/buildapp/step6/exampleappwindow.cc   | 11 +++++-----
 examples/book/buildapp/step7/exampleappwindow.cc   | 20 ++++++++----------
 examples/book/buildapp/step8/exampleappwindow.cc   | 24 ++++++++++------------
 examples/book/buildapp/step9/exampleappwindow.cc   | 24 ++++++++++------------
 examples/book/builder/basic/main.cc                |  5 ++---
 examples/book/builder/derived/deriveddialog.cc     |  2 +-
 examples/book/builder/derived/main.cc              |  5 ++---
 examples/book/menus/main_menu/examplewindow.cc     |  3 +--
 examples/book/menus_and_toolbars/examplewindow.cc  |  3 +--
 examples/book/printing/advanced/examplewindow.cc   |  3 +--
 examples/book/printing/simple/examplewindow.cc     |  3 +--
 examples/book/recent_files/examplewindow.cc        |  3 +--
 18 files changed, 56 insertions(+), 76 deletions(-)
---
diff --git a/examples/book/buildapp/step2/exampleappwindow.cc 
b/examples/book/buildapp/step2/exampleappwindow.cc
index 091aae8..1be4222 100644
--- a/examples/book/buildapp/step2/exampleappwindow.cc
+++ b/examples/book/buildapp/step2/exampleappwindow.cc
@@ -29,8 +29,7 @@ ExampleAppWindow* ExampleAppWindow::create()
   // Load the Builder file and instantiate its widgets.
   auto refBuilder = Gtk::Builder::create_from_resource("/org/gtkmm/exampleapp/window.ui");
 
-  ExampleAppWindow* window = nullptr;
-  Gtk::Builder::get_widget_derived(refBuilder, "app_window", window);
+  auto window = Gtk::Builder::get_widget_derived<ExampleAppWindow>(refBuilder, "app_window");
   if (!window)
     throw std::runtime_error("No \"app_window\" object in window.ui");
 
diff --git a/examples/book/buildapp/step3/exampleappwindow.cc 
b/examples/book/buildapp/step3/exampleappwindow.cc
index 8068b9e..806369c 100644
--- a/examples/book/buildapp/step3/exampleappwindow.cc
+++ b/examples/book/buildapp/step3/exampleappwindow.cc
@@ -23,7 +23,7 @@ ExampleAppWindow::ExampleAppWindow(BaseObjectType* cobject,
   m_refBuilder(refBuilder),
   m_stack(nullptr)
 {
-  m_refBuilder->get_widget("stack", m_stack);
+  m_stack = m_refBuilder->get_widget<Gtk::Stack>("stack");
   if (!m_stack)
     throw std::runtime_error("No \"stack\" object in window.ui");
 }
@@ -34,8 +34,7 @@ ExampleAppWindow* ExampleAppWindow::create()
   // Load the Builder file and instantiate its widgets.
   auto refBuilder = Gtk::Builder::create_from_resource("/org/gtkmm/exampleapp/window.ui");
 
-  ExampleAppWindow* window = nullptr;
-  Gtk::Builder::get_widget_derived(refBuilder, "app_window", window);
+  auto window = Gtk::Builder::get_widget_derived<ExampleAppWindow>(refBuilder, "app_window");
   if (!window)
     throw std::runtime_error("No \"app_window\" object in window.ui");
 
diff --git a/examples/book/buildapp/step4/exampleapplication.cc 
b/examples/book/buildapp/step4/exampleapplication.cc
index d890acd..4e08d47 100644
--- a/examples/book/buildapp/step4/exampleapplication.cc
+++ b/examples/book/buildapp/step4/exampleapplication.cc
@@ -69,8 +69,7 @@ void ExampleApplication::on_startup()
     return;
   }
 
-  auto object = refBuilder->get_object("appmenu");
-  auto app_menu = std::dynamic_pointer_cast<Gio::MenuModel>(object);
+  auto app_menu = refBuilder->get_object<Gio::MenuModel>("appmenu");
   if (app_menu)
     set_app_menu(app_menu);
   else
diff --git a/examples/book/buildapp/step5/exampleapplication.cc 
b/examples/book/buildapp/step5/exampleapplication.cc
index f729f03..75e16c1 100644
--- a/examples/book/buildapp/step5/exampleapplication.cc
+++ b/examples/book/buildapp/step5/exampleapplication.cc
@@ -70,8 +70,7 @@ void ExampleApplication::on_startup()
     return;
   }
 
-  auto object = refBuilder->get_object("appmenu");
-  auto app_menu = std::dynamic_pointer_cast<Gio::MenuModel>(object);
+  auto app_menu = refBuilder->get_object<Gio::MenuModel>("appmenu");
   if (app_menu)
     set_app_menu(app_menu);
   else
diff --git a/examples/book/buildapp/step5/exampleappprefs.cc b/examples/book/buildapp/step5/exampleappprefs.cc
index 97c7aa3..b599cde 100644
--- a/examples/book/buildapp/step5/exampleappprefs.cc
+++ b/examples/book/buildapp/step5/exampleappprefs.cc
@@ -25,11 +25,11 @@ ExampleAppPrefs::ExampleAppPrefs(BaseObjectType* cobject,
   m_font(nullptr),
   m_transition(nullptr)
 {
-  m_refBuilder->get_widget("font", m_font);
+  m_font = m_refBuilder->get_widget<Gtk::FontButton>("font");
   if (!m_font)
     throw std::runtime_error("No \"font\" object in prefs.ui");
 
-  m_refBuilder->get_widget("transition", m_transition);
+  m_transition = m_refBuilder->get_widget<Gtk::ComboBoxText>("transition");
   if (!m_transition)
     throw std::runtime_error("No \"transition\" object in prefs.ui");
 
@@ -44,8 +44,7 @@ ExampleAppPrefs* ExampleAppPrefs::create(Gtk::Window& parent)
   // Load the Builder file and instantiate its widgets.
   auto refBuilder = Gtk::Builder::create_from_resource("/org/gtkmm/exampleapp/prefs.ui");
 
-  ExampleAppPrefs* dialog = nullptr;
-  Gtk::Builder::get_widget_derived(refBuilder, "prefs_dialog", dialog);
+  auto dialog = Gtk::Builder::get_widget_derived<ExampleAppPrefs>(refBuilder, "prefs_dialog");
   if (!dialog)
     throw std::runtime_error("No \"prefs_dialog\" object in prefs.ui");
 
diff --git a/examples/book/buildapp/step5/exampleappwindow.cc 
b/examples/book/buildapp/step5/exampleappwindow.cc
index b4ed34e..2e7d5ea 100644
--- a/examples/book/buildapp/step5/exampleappwindow.cc
+++ b/examples/book/buildapp/step5/exampleappwindow.cc
@@ -24,7 +24,7 @@ ExampleAppWindow::ExampleAppWindow(BaseObjectType* cobject,
   m_settings(),
   m_stack(nullptr)
 {
-  m_refBuilder->get_widget("stack", m_stack);
+  m_stack = m_refBuilder->get_widget<Gtk::Stack>("stack");
   if (!m_stack)
     throw std::runtime_error("No \"stack\" object in window.ui");
 
@@ -38,8 +38,7 @@ ExampleAppWindow* ExampleAppWindow::create()
   // Load the Builder file and instantiate its widgets.
   auto refBuilder = Gtk::Builder::create_from_resource("/org/gtkmm/exampleapp/window.ui");
 
-  ExampleAppWindow* window = nullptr;
-  Gtk::Builder::get_widget_derived(refBuilder, "app_window", window);
+  auto window = Gtk::Builder::get_widget_derived<ExampleAppWindow>(refBuilder, "app_window");
   if (!window)
     throw std::runtime_error("No \"app_window\" object in window.ui");
 
diff --git a/examples/book/buildapp/step6/exampleappwindow.cc 
b/examples/book/buildapp/step6/exampleappwindow.cc
index 757cdc6..6a26f7d 100644
--- a/examples/book/buildapp/step6/exampleappwindow.cc
+++ b/examples/book/buildapp/step6/exampleappwindow.cc
@@ -28,19 +28,19 @@ ExampleAppWindow::ExampleAppWindow(BaseObjectType* cobject,
   m_searchentry(nullptr),
   m_prop_binding()
 {
-  m_refBuilder->get_widget("stack", m_stack);
+  m_stack = m_refBuilder->get_widget<Gtk::Stack>("stack");
   if (!m_stack)
     throw std::runtime_error("No \"stack\" object in window.ui");
 
-  m_refBuilder->get_widget("search", m_search);
+  m_search = m_refBuilder->get_widget<Gtk::ToggleButton>("search");
   if (!m_search)
     throw std::runtime_error("No \"search\" object in window.ui");
 
-  m_refBuilder->get_widget("searchbar", m_searchbar);
+  m_searchbar = m_refBuilder->get_widget<Gtk::SearchBar>("searchbar");
   if (!m_searchbar)
     throw std::runtime_error("No \"searchbar\" object in window.ui");
 
-  m_refBuilder->get_widget("searchentry", m_searchentry);
+  m_searchentry = m_refBuilder->get_widget<Gtk::SearchEntry>("searchentry");
   if (!m_searchentry)
     throw std::runtime_error("No \"searchentry\" object in window.ui");
 
@@ -63,8 +63,7 @@ ExampleAppWindow* ExampleAppWindow::create()
   // Load the Builder file and instantiate its widgets.
   auto refBuilder = Gtk::Builder::create_from_resource("/org/gtkmm/exampleapp/window.ui");
 
-  ExampleAppWindow* window = nullptr;
-  Gtk::Builder::get_widget_derived(refBuilder, "app_window", window);
+  auto window = Gtk::Builder::get_widget_derived<ExampleAppWindow>(refBuilder, "app_window");
   if (!window)
     throw std::runtime_error("No \"app_window\" object in window.ui");
 
diff --git a/examples/book/buildapp/step7/exampleappwindow.cc 
b/examples/book/buildapp/step7/exampleappwindow.cc
index 092aaf8..20cf42b 100644
--- a/examples/book/buildapp/step7/exampleappwindow.cc
+++ b/examples/book/buildapp/step7/exampleappwindow.cc
@@ -33,31 +33,31 @@ ExampleAppWindow::ExampleAppWindow(BaseObjectType* cobject,
   m_prop_binding()
 {
   // Get widgets from the Gtk::Builder file.
-  m_refBuilder->get_widget("stack", m_stack);
+  m_stack = m_refBuilder->get_widget<Gtk::Stack>("stack");
   if (!m_stack)
     throw std::runtime_error("No \"stack\" object in window.ui");
 
-  m_refBuilder->get_widget("search", m_search);
+  m_search = m_refBuilder->get_widget<Gtk::ToggleButton>("search");
   if (!m_search)
     throw std::runtime_error("No \"search\" object in window.ui");
 
-  m_refBuilder->get_widget("searchbar", m_searchbar);
+  m_searchbar = m_refBuilder->get_widget<Gtk::SearchBar>("searchbar");
   if (!m_searchbar)
     throw std::runtime_error("No \"searchbar\" object in window.ui");
 
-  m_refBuilder->get_widget("searchentry", m_searchentry);
+  m_searchentry = m_refBuilder->get_widget<Gtk::SearchEntry>("searchentry");
   if (!m_searchentry)
     throw std::runtime_error("No \"searchentry\" object in window.ui");
 
-  m_refBuilder->get_widget("gears", m_gears);
+  m_gears = m_refBuilder->get_widget<Gtk::MenuButton>("gears");
   if (!m_gears)
     throw std::runtime_error("No \"gears\" object in window.ui");
 
-  m_refBuilder->get_widget("sidebar", m_sidebar);
+  m_sidebar = m_refBuilder->get_widget<Gtk::Revealer>("sidebar");
   if (!m_sidebar)
     throw std::runtime_error("No \"sidebar\" object in window.ui");
 
-  m_refBuilder->get_widget("words", m_words);
+  m_words = m_refBuilder->get_widget<Gtk::ListBox>("words");
   if (!m_words)
     throw std::runtime_error("No \"words\" object in window.ui");
 
@@ -82,8 +82,7 @@ ExampleAppWindow::ExampleAppWindow(BaseObjectType* cobject,
   // to the win.show-words action and the "Words" menu item.
   // (The connection between action and menu item is specified in gears_menu.ui.)
   auto menu_builder = Gtk::Builder::create_from_resource("/org/gtkmm/exampleapp/gears_menu.ui");
-  auto object = menu_builder->get_object("menu");
-  auto menu = std::dynamic_pointer_cast<Gio::MenuModel>(object);
+  auto menu = menu_builder->get_object<Gio::MenuModel>("menu");
   if (!menu)
     throw std::runtime_error("No \"menu\" object in gears_menu.ui");
 
@@ -97,8 +96,7 @@ ExampleAppWindow* ExampleAppWindow::create()
   // Load the Builder file and instantiate its widgets.
   auto refBuilder = Gtk::Builder::create_from_resource("/org/gtkmm/exampleapp/window.ui");
 
-  ExampleAppWindow* window = nullptr;
-  Gtk::Builder::get_widget_derived(refBuilder, "app_window", window);
+  auto window = Gtk::Builder::get_widget_derived<ExampleAppWindow>(refBuilder, "app_window");
   if (!window)
     throw std::runtime_error("No \"app_window\" object in window.ui");
 
diff --git a/examples/book/buildapp/step8/exampleappwindow.cc 
b/examples/book/buildapp/step8/exampleappwindow.cc
index 63fb303..4282e7b 100644
--- a/examples/book/buildapp/step8/exampleappwindow.cc
+++ b/examples/book/buildapp/step8/exampleappwindow.cc
@@ -36,39 +36,39 @@ ExampleAppWindow::ExampleAppWindow(BaseObjectType* cobject,
   m_binding_lines_visible()
 {
   // Get widgets from the Gtk::Builder file.
-  m_refBuilder->get_widget("stack", m_stack);
+  m_stack = m_refBuilder->get_widget<Gtk::Stack>("stack");
   if (!m_stack)
     throw std::runtime_error("No \"stack\" object in window.ui");
 
-  m_refBuilder->get_widget("search", m_search);
+  m_search = m_refBuilder->get_widget<Gtk::ToggleButton>("search");
   if (!m_search)
     throw std::runtime_error("No \"search\" object in window.ui");
 
-  m_refBuilder->get_widget("searchbar", m_searchbar);
+  m_searchbar = m_refBuilder->get_widget<Gtk::SearchBar>("searchbar");
   if (!m_searchbar)
     throw std::runtime_error("No \"searchbar\" object in window.ui");
 
-  m_refBuilder->get_widget("searchentry", m_searchentry);
+  m_searchentry = m_refBuilder->get_widget<Gtk::SearchEntry>("searchentry");
   if (!m_searchentry)
     throw std::runtime_error("No \"searchentry\" object in window.ui");
 
-  m_refBuilder->get_widget("gears", m_gears);
+  m_gears = m_refBuilder->get_widget<Gtk::MenuButton>("gears");
   if (!m_gears)
     throw std::runtime_error("No \"gears\" object in window.ui");
 
-  m_refBuilder->get_widget("sidebar", m_sidebar);
+  m_sidebar = m_refBuilder->get_widget<Gtk::Revealer>("sidebar");
   if (!m_sidebar)
     throw std::runtime_error("No \"sidebar\" object in window.ui");
 
-  m_refBuilder->get_widget("words", m_words);
+  m_words = m_refBuilder->get_widget<Gtk::ListBox>("words");
   if (!m_words)
     throw std::runtime_error("No \"words\" object in window.ui");
 
-  m_refBuilder->get_widget("lines", m_lines);
+  m_lines = m_refBuilder->get_widget<Gtk::Label>("lines");
   if (!m_lines)
     throw std::runtime_error("No \"lines\" object in window.ui");
 
-  m_refBuilder->get_widget("lines_label", m_lines_label);
+  m_lines_label = m_refBuilder->get_widget<Gtk::Label>("lines_label");
   if (!m_lines_label)
     throw std::runtime_error("No \"lines_label\" object in window.ui");
 
@@ -93,8 +93,7 @@ ExampleAppWindow::ExampleAppWindow(BaseObjectType* cobject,
   // to the win.show-words action and the "Words" menu item.
   // (The connection between action and menu item is specified in gears_menu.ui.)
   auto menu_builder = Gtk::Builder::create_from_resource("/org/gtkmm/exampleapp/gears_menu.ui");
-  auto object = menu_builder->get_object("menu");
-  auto menu = std::dynamic_pointer_cast<Gio::MenuModel>(object);
+  auto menu = menu_builder->get_object<Gio::MenuModel>("menu");
   if (!menu)
     throw std::runtime_error("No \"menu\" object in gears_menu.ui");
 
@@ -114,8 +113,7 @@ ExampleAppWindow* ExampleAppWindow::create()
   // Load the Builder file and instantiate its widgets.
   auto refBuilder = Gtk::Builder::create_from_resource("/org/gtkmm/exampleapp/window.ui");
 
-  ExampleAppWindow* window = nullptr;
-  Gtk::Builder::get_widget_derived(refBuilder, "app_window", window);
+  auto window = Gtk::Builder::get_widget_derived<ExampleAppWindow>(refBuilder, "app_window");
   if (!window)
     throw std::runtime_error("No \"app_window\" object in window.ui");
 
diff --git a/examples/book/buildapp/step9/exampleappwindow.cc 
b/examples/book/buildapp/step9/exampleappwindow.cc
index 0b6d7dc..3cc57ef 100644
--- a/examples/book/buildapp/step9/exampleappwindow.cc
+++ b/examples/book/buildapp/step9/exampleappwindow.cc
@@ -36,39 +36,39 @@ ExampleAppWindow::ExampleAppWindow(BaseObjectType* cobject,
   m_binding_lines_visible()
 {
   // Get widgets from the Gtk::Builder file.
-  m_refBuilder->get_widget("stack", m_stack);
+  m_stack = m_refBuilder->get_widget<Gtk::Stack>("stack");
   if (!m_stack)
     throw std::runtime_error("No \"stack\" object in window.ui");
 
-  m_refBuilder->get_widget("search", m_search);
+  m_search = m_refBuilder->get_widget<Gtk::ToggleButton>("search");
   if (!m_search)
     throw std::runtime_error("No \"search\" object in window.ui");
 
-  m_refBuilder->get_widget("searchbar", m_searchbar);
+  m_searchbar = m_refBuilder->get_widget<Gtk::SearchBar>("searchbar");
   if (!m_searchbar)
     throw std::runtime_error("No \"searchbar\" object in window.ui");
 
-  m_refBuilder->get_widget("searchentry", m_searchentry);
+  m_searchentry = m_refBuilder->get_widget<Gtk::SearchEntry>("searchentry");
   if (!m_searchentry)
     throw std::runtime_error("No \"searchentry\" object in window.ui");
 
-  m_refBuilder->get_widget("gears", m_gears);
+  m_gears = m_refBuilder->get_widget<Gtk::MenuButton>("gears");
   if (!m_gears)
     throw std::runtime_error("No \"gears\" object in window.ui");
 
-  m_refBuilder->get_widget("sidebar", m_sidebar);
+  m_sidebar = m_refBuilder->get_widget<Gtk::Revealer>("sidebar");
   if (!m_sidebar)
     throw std::runtime_error("No \"sidebar\" object in window.ui");
 
-  m_refBuilder->get_widget("words", m_words);
+  m_words = m_refBuilder->get_widget<Gtk::ListBox>("words");
   if (!m_words)
     throw std::runtime_error("No \"words\" object in window.ui");
 
-  m_refBuilder->get_widget("lines", m_lines);
+  m_lines = m_refBuilder->get_widget<Gtk::Label>("lines");
   if (!m_lines)
     throw std::runtime_error("No \"lines\" object in window.ui");
 
-  m_refBuilder->get_widget("lines_label", m_lines_label);
+  m_lines_label = m_refBuilder->get_widget<Gtk::Label>("lines_label");
   if (!m_lines_label)
     throw std::runtime_error("No \"lines_label\" object in window.ui");
 
@@ -93,8 +93,7 @@ ExampleAppWindow::ExampleAppWindow(BaseObjectType* cobject,
   // to the win.show-words action and the "Words" menu item.
   // (The connection between action and menu item is specified in gears_menu.ui.)
   auto menu_builder = Gtk::Builder::create_from_resource("/org/gtkmm/exampleapp/gears_menu.ui");
-  auto object = menu_builder->get_object("menu");
-  auto menu = std::dynamic_pointer_cast<Gio::MenuModel>(object);
+  auto menu = menu_builder->get_object<Gio::MenuModel>("menu");
   if (!menu)
     throw std::runtime_error("No \"menu\" object in gears_menu.ui");
 
@@ -124,8 +123,7 @@ ExampleAppWindow* ExampleAppWindow::create()
   // Load the Builder file and instantiate its widgets.
   auto refBuilder = Gtk::Builder::create_from_resource("/org/gtkmm/exampleapp/window.ui");
 
-  ExampleAppWindow* window = nullptr;
-  Gtk::Builder::get_widget_derived(refBuilder, "app_window", window);
+  auto window = Gtk::Builder::get_widget_derived<ExampleAppWindow>(refBuilder, "app_window");
   if (!window)
     throw std::runtime_error("No \"app_window\" object in window.ui");
 
diff --git a/examples/book/builder/basic/main.cc b/examples/book/builder/basic/main.cc
index b27cf0f..b840b42 100644
--- a/examples/book/builder/basic/main.cc
+++ b/examples/book/builder/basic/main.cc
@@ -37,12 +37,11 @@ int main (int argc, char **argv)
   }
 
   //Get the GtkBuilder-instantiated Dialog:
-  refBuilder->get_widget("DialogBasic", pDialog);
+  pDialog = refBuilder->get_widget<Gtk::Dialog>("DialogBasic");
   if(pDialog)
   {
     //Get the GtkBuilder-instantiated Button, and connect a signal handler:
-    Gtk::Button* pButton = nullptr;
-    refBuilder->get_widget("quit_button", pButton);
+    auto pButton = refBuilder->get_widget<Gtk::Button>("quit_button");
     if(pButton)
     {
       pButton->signal_clicked().connect( sigc::ptr_fun(on_button_clicked) );
diff --git a/examples/book/builder/derived/deriveddialog.cc b/examples/book/builder/derived/deriveddialog.cc
index b37c119..e41e720 100644
--- a/examples/book/builder/derived/deriveddialog.cc
+++ b/examples/book/builder/derived/deriveddialog.cc
@@ -22,7 +22,7 @@ DerivedDialog::DerivedDialog(BaseObjectType* cobject, const Glib::RefPtr<Gtk::Bu
   m_pButton(nullptr)
 {
   //Get the Glade-instantiated Button, and connect a signal handler:
-  m_refGlade->get_widget("quit_button", m_pButton);
+  m_pButton = m_refGlade->get_widget<Gtk::Button>("quit_button");
   if(m_pButton)
   {
     m_pButton->signal_clicked().connect( sigc::mem_fun(*this, &DerivedDialog::on_button_quit) );
diff --git a/examples/book/builder/derived/main.cc b/examples/book/builder/derived/main.cc
index a46458c..6ef78d2 100644
--- a/examples/book/builder/derived/main.cc
+++ b/examples/book/builder/derived/main.cc
@@ -66,10 +66,9 @@ int main (int argc, char **argv)
   //Get the GtkBuilder-instantiated dialog:
   DerivedDialog* pDialog = nullptr;
   if (show_icon)
-    // This call to get_widget_derived() requires gtkmm 3.19.7 or higher.
-    Gtk::Builder::get_widget_derived(refBuilder, "DialogDerived", pDialog, is_glad);
+    pDialog = Gtk::Builder::get_widget_derived<DerivedDialog>(refBuilder, "DialogDerived", is_glad);
   else
-    Gtk::Builder::get_widget_derived(refBuilder, "DialogDerived", pDialog);
+    pDialog = Gtk::Builder::get_widget_derived<DerivedDialog>(refBuilder, "DialogDerived");
   if(pDialog)
   {
     //Start:
diff --git a/examples/book/menus/main_menu/examplewindow.cc b/examples/book/menus/main_menu/examplewindow.cc
index 8605fb7..8d2f90f 100644
--- a/examples/book/menus/main_menu/examplewindow.cc
+++ b/examples/book/menus/main_menu/examplewindow.cc
@@ -95,8 +95,7 @@ ExampleWindow::ExampleWindow()
     std::cerr << "Building toolbar failed: " <<  ex.what();
   }
 
-  Gtk::Toolbar* toolbar = nullptr;
-  m_refBuilder->get_widget("toolbar", toolbar);
+  auto toolbar = m_refBuilder->get_widget<Gtk::Toolbar>("toolbar");
   if (!toolbar)
     g_warning("GtkToolbar not found");
   else
diff --git a/examples/book/menus_and_toolbars/examplewindow.cc 
b/examples/book/menus_and_toolbars/examplewindow.cc
index f18771f..dcfc441 100644
--- a/examples/book/menus_and_toolbars/examplewindow.cc
+++ b/examples/book/menus_and_toolbars/examplewindow.cc
@@ -143,8 +143,7 @@ ExampleWindow::ExampleWindow(const Glib::RefPtr<Gtk::Application>& app)
   }
 
   //Get the toolbar and add it to a container widget:
-  Gtk::Toolbar* toolbar = nullptr;
-  m_refBuilder->get_widget("toolbar", toolbar);
+  auto toolbar = m_refBuilder->get_widget<Gtk::Toolbar>("toolbar");
   if (!toolbar)
     g_warning("GtkToolbar not found");
   else
diff --git a/examples/book/printing/advanced/examplewindow.cc 
b/examples/book/printing/advanced/examplewindow.cc
index df84f7b..b20d80a 100644
--- a/examples/book/printing/advanced/examplewindow.cc
+++ b/examples/book/printing/advanced/examplewindow.cc
@@ -221,8 +221,7 @@ void ExampleWindow::build_main_menu(const Glib::RefPtr<Gtk::Application>& app)
   }
 
   // Get the toolbar and add it to a container widget:
-  Gtk::Toolbar* toolbar = nullptr;
-  m_refBuilder->get_widget("toolbar", toolbar);
+  auto toolbar = m_refBuilder->get_widget<Gtk::Toolbar>("toolbar");
   if (!toolbar)
     g_warning("GtkToolbar not found");
   else
diff --git a/examples/book/printing/simple/examplewindow.cc b/examples/book/printing/simple/examplewindow.cc
index e767d69..03cad7e 100644
--- a/examples/book/printing/simple/examplewindow.cc
+++ b/examples/book/printing/simple/examplewindow.cc
@@ -222,8 +222,7 @@ void ExampleWindow::build_main_menu(const Glib::RefPtr<Gtk::Application>& app)
   }
 
   // Get the toolbar and add it to a container widget:
-  Gtk::Toolbar* toolbar = nullptr;
-  m_refBuilder->get_widget("toolbar", toolbar);
+  auto toolbar = m_refBuilder->get_widget<Gtk::Toolbar>("toolbar");
   if (!toolbar)
     g_warning("GtkToolbar not found");
   else
diff --git a/examples/book/recent_files/examplewindow.cc b/examples/book/recent_files/examplewindow.cc
index 704701f..51b482b 100644
--- a/examples/book/recent_files/examplewindow.cc
+++ b/examples/book/recent_files/examplewindow.cc
@@ -123,8 +123,7 @@ ExampleWindow::ExampleWindow(const Glib::RefPtr<Gtk::Application>& app)
   else
     g_warning("GMenu not found");
 
-  Gtk::Toolbar* pToolbar = nullptr;
-  m_refBuilder->get_widget("toolbar", pToolbar);
+  auto pToolbar = m_refBuilder->get_widget<Gtk::Toolbar>("toolbar");
   if (pToolbar)
     //Toolbar:
     m_Box.add(*pToolbar);