[gtkmm-documentation] Adapt to latest versions of gtk+ and gtkmm

[Kjell Ahlstedt <kjellahl src gnome org>]

commit 66aedac7feefad0323b3c784b4bb3de7a06e1e47
Author: Kjell Ahlstedt <kjellahlstedt gmail com>
Date:   Fri Nov 3 18:35:39 2017 +0100

    Adapt to latest versions of gtk+ and gtkmm
    
    Window icons and AboutDialog logos are cairo surfaces.
    Gdk::Screen is gone. It's replaced by Gdk::Display.

 examples/book/buildapp/step9/exampleappwindow.cc   |    3 ++-
 examples/book/dialogs/aboutdialog/examplewindow.cc |    3 ++-
 examples/book/toolpalette/canvas.h                 |    2 +-
 examples/book/toolpalette/examplewindow.cc         |    6 +++++-
 4 files changed, 10 insertions(+), 4 deletions(-)
---
diff --git a/examples/book/buildapp/step9/exampleappwindow.cc 
b/examples/book/buildapp/step9/exampleappwindow.cc
index 1cfb83c..63acd68 100644
--- a/examples/book/buildapp/step9/exampleappwindow.cc
+++ b/examples/book/buildapp/step9/exampleappwindow.cc
@@ -114,7 +114,8 @@ ExampleAppWindow::ExampleAppWindow(BaseObjectType* cobject,
   set_show_menubar(true);
 
   // Set the window icon.
-  set_icon(Gdk::Pixbuf::create_from_resource("/org/gtkmm/exampleapp/exampleapp.png"));
+  set_icon(Gdk::Cairo::create_surface_from_pixbuf(
+    Gdk::Pixbuf::create_from_resource("/org/gtkmm/exampleapp/exampleapp.png"), 1));
 }
 
 //static
diff --git a/examples/book/dialogs/aboutdialog/examplewindow.cc 
b/examples/book/dialogs/aboutdialog/examplewindow.cc
index 0574f73..aa00884 100644
--- a/examples/book/dialogs/aboutdialog/examplewindow.cc
+++ b/examples/book/dialogs/aboutdialog/examplewindow.cc
@@ -39,7 +39,8 @@ ExampleWindow::ExampleWindow()
 
   m_Dialog.set_transient_for(*this);
 
-  m_Dialog.set_logo(Gdk::Pixbuf::create_from_resource("/about/gtkmm_logo.gif", -1, 40, true));
+  m_Dialog.set_logo(Gdk::Cairo::create_surface_from_pixbuf(
+    Gdk::Pixbuf::create_from_resource("/about/gtkmm_logo.gif", -1, 40, true), 1));
   m_Dialog.set_program_name("Example application");
   m_Dialog.set_version("1.0.0");
   m_Dialog.set_copyright("Murray Cumming");
diff --git a/examples/book/toolpalette/canvas.h b/examples/book/toolpalette/canvas.h
index b4aaded..d944b31 100644
--- a/examples/book/toolpalette/canvas.h
+++ b/examples/book/toolpalette/canvas.h
@@ -39,7 +39,7 @@ private:
       if (icon_name.empty())
         icon_name = button->get_label();
 
-      auto icon_theme = Gtk::IconTheme::get_for_screen(canvas->get_screen());
+      auto icon_theme = Gtk::IconTheme::get_for_display(canvas->get_display());
       int width = 0;
       int height = 0; //ignored
       Gtk::IconSize::lookup(Gtk::BuiltinIconSize::DIALOG, width, height);
diff --git a/examples/book/toolpalette/examplewindow.cc b/examples/book/toolpalette/examplewindow.cc
index 562011f..6a1919a 100644
--- a/examples/book/toolpalette/examplewindow.cc
+++ b/examples/book/toolpalette/examplewindow.cc
@@ -19,7 +19,7 @@
 
 void ExampleWindow::load_icon_items()
 {
-  auto icon_theme = Gtk::IconTheme::get_for_screen(get_screen());
+  auto icon_theme = Gtk::IconTheme::get_for_display(get_display());
 
   typedef std::vector<Glib::ustring> type_stringvec;
   type_stringvec icon_names = icon_theme->list_icons();
@@ -58,6 +58,10 @@ void ExampleWindow::load_icon_items()
         // that can't be loaded.
         continue;
       }
+      catch (const Gdk::PixbufError& /* ex */)
+      {
+        continue;
+      }
 
       // Skip large icons, just to make the ToolPalette look better.
       if (pixbuf->get_width() > 2*requested_icon_size ||