[gnome-sudoku] Keep the Cancel button sensitive after clicking Print

[Michael Catanzaro <mcatanzaro src gnome org>]

commit 5c73b73d3b4bc1ffbdb9ff1e5e3b5cb0f8d96370
Author: Iulian Radu <iulian radu67 gmail com>
Date:   Tue Mar 17 11:15:36 2015 +0200

    Keep the Cancel button sensitive after clicking Print
    
    If the user clicks Print, the Cancel button should remain sensitive.
    Pressing Cancel should stop the Print operation
    
    https://bugzilla.gnome.org/show_bug.cgi?id=736773

 lib/sudoku-generator.vala |    3 ++-
 src/gnome-sudoku.vala     |    6 +++---
 src/print-dialog.vala     |   28 ++++++++++++++++++++++++----
 3 files changed, 29 insertions(+), 8 deletions(-)
---
diff --git a/lib/sudoku-generator.vala b/lib/sudoku-generator.vala
index 0ae7c1e..fc2fcb3 100644
--- a/lib/sudoku-generator.vala
+++ b/lib/sudoku-generator.vala
@@ -80,7 +80,7 @@ public class SudokuGenerator : Object
         return board;
     }
 
-    public async static Gee.List<SudokuBoard> generate_boards_async (int nboards, DifficultyCategory 
category) throws ThreadError
+    public async static Gee.List<SudokuBoard> generate_boards_async (int nboards, DifficultyCategory 
category, Cancellable? cancellable) throws ThreadError, IOError
     {
         var boards = new ArrayList<SudokuBoard> ();
         var pool = new ThreadPool<Worker>.with_owned_data ((worker) => {
@@ -93,6 +93,7 @@ public class SudokuGenerator : Object
         }
 
         yield;
+        cancellable.set_error_if_cancelled ();
         return boards;
     }
 
diff --git a/src/gnome-sudoku.vala b/src/gnome-sudoku.vala
index 555cdfa..789aed8 100644
--- a/src/gnome-sudoku.vala
+++ b/src/gnome-sudoku.vala
@@ -405,13 +405,13 @@ public class Sudoku : Gtk.Application
 
         back_button.sensitive = false;
 
-        SudokuGenerator.generate_boards_async.begin (1, selected_difficulty, (obj, res) => {
+        SudokuGenerator.generate_boards_async.begin (1, selected_difficulty, null, (obj, res) => {
             try {
                 var gen_boards = SudokuGenerator.generate_boards_async.end (res);
                 back_button.sensitive = true;
                 start_game (gen_boards[0]);
-            } catch (ThreadError e) {
-                error ("Thread error: %s", e.message);
+            } catch (Error e) {
+                error ("Error: %s", e.message);
             }
         });
     }
diff --git a/src/print-dialog.vala b/src/print-dialog.vala
index a96278b..1be7ef5 100644
--- a/src/print-dialog.vala
+++ b/src/print-dialog.vala
@@ -26,6 +26,10 @@ public class PrintDialog : Gtk.Dialog
     private Settings settings;
 
     [GtkChild]
+    private Gtk.Button print_button;
+    [GtkChild]
+    private Gtk.Box print_box;
+    [GtkChild]
     private Gtk.SpinButton n_sudokus_button;
     [GtkChild]
     private Gtk.RadioButton easy_radio_button;
@@ -39,12 +43,14 @@ public class PrintDialog : Gtk.Dialog
     private Gtk.Revealer revealer;
     private Gtk.Spinner spinner;
 
-    private const string DIFFICULTY_KEY_NAME = "print-multiple-sudoku-difficulty";
+    private Cancellable cancellable;
 
     /* After emitting our response, we continue to asynchronously generate puzzles
        in the background. This signal indicates when we are really finished. */
     public signal void finished ();
 
+    private const string DIFFICULTY_KEY_NAME = "print-multiple-sudoku-difficulty";
+
     public PrintDialog (SudokuSaver saver, Gtk.Window window)
     {
         Object (use_header_bar: Gtk.Settings.get_default ().gtk_dialogs_use_header ? 1 : 0);
@@ -52,6 +58,12 @@ public class PrintDialog : Gtk.Dialog
         this.saver = saver;
         settings = new GLib.Settings ("org.gnome.sudoku");
 
+        this.response.connect ((response_id) => {
+            if (response_id == Gtk.ResponseType.CANCEL || response_id == Gtk.ResponseType.DELETE_EVENT) {
+                cancellable.cancel ();
+            }
+        });
+
         set_transient_for (window);
 
         spinner = new Gtk.Spinner ();
@@ -128,16 +140,17 @@ public class PrintDialog : Gtk.Dialog
 
         Timeout.add_seconds (3, (SourceFunc) start_spinner_cb);
 
-        sensitive = false;
+        print_button.sensitive = false;
+        print_box.sensitive = false;
 
-        SudokuGenerator.generate_boards_async.begin (nsudokus, level, (obj, res) => {
+        cancellable = new Cancellable ();
+        SudokuGenerator.generate_boards_async.begin (nsudokus, level, cancellable, (obj, res) => {
             try
             {
                 var boards = SudokuGenerator.generate_boards_async.end (res);
 
                 spinner.stop ();
                 revealer.hide ();
-                sensitive = true;
 
                 var printer = new SudokuPrinter (boards, this);
                 if (printer.print_sudoku () == Gtk.PrintOperationResult.APPLY)
@@ -150,6 +163,13 @@ public class PrintDialog : Gtk.Dialog
             {
                 error ("Thread error: %s\n", e.message);
             }
+            catch (IOError e)
+            {
+                if (!(e is IOError.CANCELLED))
+                {
+                    warning ("Error: %s\n", e.message);
+                }
+            }
 
             finished ();
         });