Modeless Preferences and Accounts dialog: Closes #5012

src/client/accounts/account-dialog.vala

@@ -7,6 +7,8 @@
 public class AccountDialog : Gtk.Dialog {
     private const int MARGIN = 12;
     
+    private static AccountDialog? account_dialog = null;
+    
     private Gtk.Notebook notebook = new Gtk.Notebook();
     private AccountDialogAccountListPane account_list_pane;
     private AccountDialogAddEditPane add_edit_pane;
@@ -14,7 +16,7 @@ public class AccountDialog : Gtk.Dialog {
     private AccountDialogRemoveConfirmPane remove_confirm_pane;
     private AccountDialogRemoveFailPane remove_fail_pane;
     
-    public AccountDialog() {
+    private AccountDialog() {
         set_size_request(450, -1); // Sets min size.
         title = _("Accounts");
         get_content_area().margin_top = MARGIN;
@@ -39,6 +41,8 @@ public class AccountDialog : Gtk.Dialog {
         remove_confirm_pane.ok.connect(on_delete_account_confirmed);
         remove_confirm_pane.cancel.connect(on_cancel_back_to_list);
         remove_fail_pane.ok.connect(on_cancel_back_to_list);
+        delete_event.connect(on_delete);
+        response.connect(on_close);
         
         // Set default page.
         account_list_pane.present();
@@ -52,8 +56,20 @@ public class AccountDialog : Gtk.Dialog {
         notebook.show_all(); // Required due to longstanding Gtk.Notebook bug
     }
     
+    public static void show_instance() {
+        if (account_dialog == null) {
+            account_dialog = new AccountDialog();
+        }
+        account_dialog.show_all();
+        account_dialog.present();
+    }
+    
+    private bool on_delete() {
+        return hide_on_delete();
+    }
+    
     private void on_close() {
-        destroy();
+        hide();
     }
     
     private void on_add_account() {

src/client/dialogs/preferences-dialog.vala

@@ -5,6 +5,8 @@
  */
 
 public class PreferencesDialog : Object {
+    private static PreferencesDialog? preferences_dialog = null;
+    
     private Gtk.Dialog dialog;
     private Gtk.CheckButton autoselect;
     private Gtk.CheckButton display_preview;
@@ -14,7 +16,7 @@ public class PreferencesDialog : Object {
     private Gtk.Button close_button;
     private Configuration config;
     
-    public PreferencesDialog(Configuration config) {
+    private PreferencesDialog(Configuration config) {
         this.config = config;
         Gtk.Builder builder = GearyApplication.instance.create_builder("preferences.glade");
         
@@ -27,12 +29,7 @@ public class PreferencesDialog : Object {
         show_notifications = builder.get_object("show_notifications") as Gtk.CheckButton;
         close_button = builder.get_object("close_button") as Gtk.Button;
         
-        // Populate the dialog with our current settings.
-        autoselect.active = config.autoselect;
-        display_preview.active = config.display_preview;
-        spell_check.active = config.spell_check;
-        play_sounds.active = config.play_sounds;
-        show_notifications.active = config.show_notifications;
+        populate_preference_options();
         
         // Connect to element signals.
         autoselect.toggled.connect(on_autoselect_toggled);
@@ -41,19 +38,33 @@ public class PreferencesDialog : Object {
         play_sounds.toggled.connect(on_play_sounds_toggled);
         show_notifications.toggled.connect(on_show_notifications_toggled);
         
-        GearyApplication.instance.exiting.connect(on_exit);
+        dialog.delete_event.connect(on_delete);
+        dialog.response.connect(on_close);
     }
     
-    public void run() {
-        if (dialog.run() != Gtk.ResponseType.NONE) {
-            dialog.destroy();
-        }
+    public void populate_preference_options() {
+        autoselect.active = config.autoselect;
+        display_preview.active = config.display_preview;
+        spell_check.active = config.spell_check;
+        play_sounds.active = config.play_sounds;
+        show_notifications.active = config.show_notifications;    
     }
     
-    private bool on_exit(bool panicked) {
-        dialog.destroy();
+    public static void show_instance() {
+        if (preferences_dialog == null) 
+            preferences_dialog = new PreferencesDialog(GearyApplication.instance.config);
         
-        return true;
+        preferences_dialog.populate_preference_options();
+        preferences_dialog.dialog.show_all();
+        preferences_dialog.dialog.present();
+    }
+    
+    private bool on_delete() {
+        return dialog.hide_on_delete(); //prevent widgets from getting destroyed
+    }
+    
+    private void on_close() {
+        dialog.hide();
     }
     
     private void on_autoselect_toggled() {

src/client/geary-controller.vala

@@ -1007,14 +1007,11 @@ public class GearyController {
     }
     
     private void on_accounts() {
-        AccountDialog dialog = new AccountDialog();
-        dialog.run();
-        dialog.destroy();
+        AccountDialog.show_instance();
     }
     
     private void on_preferences() {
-        PreferencesDialog dialog = new PreferencesDialog(GearyApplication.instance.config);
-        dialog.run();
+        PreferencesDialog.show_instance();
     }
 
     private Gee.List<Geary.EmailIdentifier> get_selected_folder_email_ids(