[geary/mjog/user-plugins: 2/26] Components.PreferencesWindow: Make application prop nullable

[Michael Gratton <mjog src gnome org>]

commit 655f1dcf831ea6c47c4b5f0f307376f570538b58
Author: Michael Gratton <mike vee net>
Date:   Mon Mar 2 10:38:08 2020 +1100

    Components.PreferencesWindow: Make application prop nullable
    
    It should be nullable because it can be null, update call sites to
    reflect this.

 .../components/components-preferences-window.vala  | 62 ++++++++++++----------
 1 file changed, 34 insertions(+), 28 deletions(-)
---
diff --git a/src/client/components/components-preferences-window.vala 
b/src/client/components/components-preferences-window.vala
index 0a159446..794f3650 100644
--- a/src/client/components/components-preferences-window.vala
+++ b/src/client/components/components-preferences-window.vala
@@ -23,7 +23,7 @@ public class Components.PreferencesWindow : Hdy.PreferencesWindow {
 
 
     /** Returns the window's associated client application instance. */
-    public new Application.Client application {
+    public new Application.Client? application {
         get { return (Application.Client) base.get_application(); }
         set { base.set_application(value); }
     }
@@ -115,32 +115,35 @@ public class Components.PreferencesWindow : Hdy.PreferencesWindow {
         window_actions.add_action_entries(WINDOW_ACTIONS, this);
         insert_action_group(Action.Window.GROUP_NAME, window_actions);
 
-        Application.Configuration config = this.application.config;
-        config.bind(
-            Application.Configuration.AUTOSELECT_KEY,
-            autoselect,
-            "state"
-        );
-        config.bind(
-            Application.Configuration.DISPLAY_PREVIEW_KEY,
-            display_preview,
-            "state"
-        );
-        config.bind(
-            Application.Configuration.FOLDER_LIST_PANE_HORIZONTAL_KEY,
-            three_pane_view,
-            "state"
-        );
-        config.bind(
-            Application.Configuration.SINGLE_KEY_SHORTCUTS,
-            single_key_shortucts,
-            "state"
-        );
-        config.bind(
-            Application.Configuration.STARTUP_NOTIFICATIONS_KEY,
-            startup_notifications,
-            "state"
-        );
+        Application.Client? application = this.application;
+        if (application != null) {
+            Application.Configuration config = application.config;
+            config.bind(
+                Application.Configuration.AUTOSELECT_KEY,
+                autoselect,
+                "state"
+            );
+            config.bind(
+                Application.Configuration.DISPLAY_PREVIEW_KEY,
+                display_preview,
+                "state"
+            );
+            config.bind(
+                Application.Configuration.FOLDER_LIST_PANE_HORIZONTAL_KEY,
+                three_pane_view,
+                "state"
+            );
+            config.bind(
+                Application.Configuration.SINGLE_KEY_SHORTCUTS,
+                single_key_shortucts,
+                "state"
+            );
+            config.bind(
+                Application.Configuration.STARTUP_NOTIFICATIONS_KEY,
+                startup_notifications,
+                "state"
+            );
+        }
 
         this.delete_event.connect(on_delete);
     }
@@ -151,7 +154,10 @@ public class Components.PreferencesWindow : Hdy.PreferencesWindow {
 
     private bool on_delete() {
         // Sync startup notification option with file state
-        this.application.autostart.sync_with_config();
+        Application.Client? application = this.application;
+        if (application != null) {
+            application.autostart.sync_with_config();
+        }
         return Gdk.EVENT_PROPAGATE;
     }