[gtkmm-documentation] buildapp: Update description of Gtk::Window::set_application()

[Kjell Ahlstedt <kjellahl src gnome org>]

commit 867865f6f6f1f44095d050de5296e3042154f4da
Author: Kjell Ahlstedt <kjellahlstedt gmail com>
Date:   Thu Nov 14 18:41:24 2019 +0100

    buildapp: Update description of Gtk::Window::set_application()
    
    * examples/book/buildapp/step[1,2,4,5]/exampleapplication.cc: Update the
    comment in create_appwindow() that describes Gtk::Application::add_window()
    and Gtk::Window::set_application(). Now they behave the same
    as a result of issue gtkmm#56.

 examples/book/buildapp/step1/exampleapplication.cc | 9 ++++-----
 examples/book/buildapp/step2/exampleapplication.cc | 9 ++++-----
 examples/book/buildapp/step4/exampleapplication.cc | 9 ++++-----
 examples/book/buildapp/step5/exampleapplication.cc | 9 ++++-----
 4 files changed, 16 insertions(+), 20 deletions(-)
---
diff --git a/examples/book/buildapp/step1/exampleapplication.cc 
b/examples/book/buildapp/step1/exampleapplication.cc
index c68b209..14a56c9 100644
--- a/examples/book/buildapp/step1/exampleapplication.cc
+++ b/examples/book/buildapp/step1/exampleapplication.cc
@@ -33,11 +33,10 @@ ExampleAppWindow* ExampleApplication::create_appwindow()
   // Make sure that the application runs for as long this window is still open.
   add_window(*appwindow);
 
-  // Gtk::Application::add_window() connects a signal handler to the window's
-  // signal_hide(). That handler removes the window from the application.
-  // If it's the last window to be removed, the application stops running.
-  // Gtk::Window::set_application() does not connect a signal handler, but is
-  // otherwise equivalent to Gtk::Application::add_window().
+  // A window can be added to an application with Gtk::Application::add_window()
+  // or Gtk::Window::set_application(). When all added windows have been hidden
+  // or removed, the application stops running (Gtk::Application::run() returns()),
+  // unless Gio::Application::hold() has been called.
 
   // Delete the window when it is hidden.
   appwindow->signal_hide().connect(sigc::bind(sigc::mem_fun(*this,
diff --git a/examples/book/buildapp/step2/exampleapplication.cc 
b/examples/book/buildapp/step2/exampleapplication.cc
index fa1cc0c..11754be 100644
--- a/examples/book/buildapp/step2/exampleapplication.cc
+++ b/examples/book/buildapp/step2/exampleapplication.cc
@@ -35,11 +35,10 @@ ExampleAppWindow* ExampleApplication::create_appwindow()
   // Make sure that the application runs for as long this window is still open.
   add_window(*appwindow);
 
-  // Gtk::Application::add_window() connects a signal handler to the window's
-  // signal_hide(). That handler removes the window from the application.
-  // If it's the last window to be removed, the application stops running.
-  // Gtk::Window::set_application() does not connect a signal handler, but is
-  // otherwise equivalent to Gtk::Application::add_window().
+  // A window can be added to an application with Gtk::Application::add_window()
+  // or Gtk::Window::set_application(). When all added windows have been hidden
+  // or removed, the application stops running (Gtk::Application::run() returns()),
+  // unless Gio::Application::hold() has been called.
 
   // Delete the window when it is hidden.
   appwindow->signal_hide().connect(sigc::bind(sigc::mem_fun(*this,
diff --git a/examples/book/buildapp/step4/exampleapplication.cc 
b/examples/book/buildapp/step4/exampleapplication.cc
index 4e08d47..706331a 100644
--- a/examples/book/buildapp/step4/exampleapplication.cc
+++ b/examples/book/buildapp/step4/exampleapplication.cc
@@ -35,11 +35,10 @@ ExampleAppWindow* ExampleApplication::create_appwindow()
   // Make sure that the application runs for as long this window is still open.
   add_window(*appwindow);
 
-  // Gtk::Application::add_window() connects a signal handler to the window's
-  // signal_hide(). That handler removes the window from the application.
-  // If it's the last window to be removed, the application stops running.
-  // Gtk::Window::set_application() does not connect a signal handler, but is
-  // otherwise equivalent to Gtk::Application::add_window().
+  // A window can be added to an application with Gtk::Application::add_window()
+  // or Gtk::Window::set_application(). When all added windows have been hidden
+  // or removed, the application stops running (Gtk::Application::run() returns()),
+  // unless Gio::Application::hold() has been called.
 
   // Delete the window when it is hidden.
   appwindow->signal_hide().connect(sigc::bind(sigc::mem_fun(*this,
diff --git a/examples/book/buildapp/step5/exampleapplication.cc 
b/examples/book/buildapp/step5/exampleapplication.cc
index 75e16c1..e2a9324 100644
--- a/examples/book/buildapp/step5/exampleapplication.cc
+++ b/examples/book/buildapp/step5/exampleapplication.cc
@@ -36,11 +36,10 @@ ExampleAppWindow* ExampleApplication::create_appwindow()
   // Make sure that the application runs for as long this window is still open.
   add_window(*appwindow);
 
-  // Gtk::Application::add_window() connects a signal handler to the window's
-  // signal_hide(). That handler removes the window from the application.
-  // If it's the last window to be removed, the application stops running.
-  // Gtk::Window::set_application() does not connect a signal handler, but is
-  // otherwise equivalent to Gtk::Application::add_window().
+  // A window can be added to an application with Gtk::Application::add_window()
+  // or Gtk::Window::set_application(). When all added windows have been hidden
+  // or removed, the application stops running (Gtk::Application::run() returns()),
+  // unless Gio::Application::hold() has been called.
 
   // Delete the window when it is hidden.
   appwindow->signal_hide().connect(sigc::bind(sigc::mem_fun(*this,