screenShield: Move background to Unlock Dialog

In addition to that, remove the ClutterBoxLayout that is set as
the layout manager of the Unlock Dialog, and apply the primary
monitor constraint to the child St.BoxLayout instead.

https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/872

js/ui/screenShield.js

@@ -4,7 +4,6 @@ const { AccountsService, Clutter, Gio,
         GLib, Graphene, Meta, Shell, St } = imports.gi;
 const Signals = imports.signals;
 
-const Background = imports.ui.background;
 const GnomeSession = imports.misc.gnomeSession;
 const Layout = imports.ui.layout;
 const OVirt = imports.gdm.oVirt;
@@ -76,15 +75,6 @@ var ScreenShield = class {
 
         this._lockScreenGroup.add_actor(this._lockScreenContents);
 
-        this._backgroundGroup = new Clutter.Actor();
-
-        this._lockScreenGroup.add_actor(this._backgroundGroup);
-        this._lockScreenGroup.set_child_below_sibling(this._backgroundGroup, null);
-        this._bgManagers = [];
-
-        this._updateBackgrounds();
-        Main.layoutManager.connect('monitors-changed', this._updateBackgrounds.bind(this));
-
         this._dragAction = new Clutter.GestureAction();
         this._dragAction.connect('gesture-begin', this._onDragBegin.bind(this));
         this._dragAction.connect('gesture-progress', this._onDragMotion.bind(this));
@@ -190,35 +180,6 @@ var ScreenShield = class {
         this._syncInhibitor();
     }
 
-    _createBackground(monitorIndex) {
-        let monitor = Main.layoutManager.monitors[monitorIndex];
-        let widget = new St.Widget({ style_class: 'screen-shield-background',
-                                     x: monitor.x,
-                                     y: monitor.y,
-                                     width: monitor.width,
-                                     height: monitor.height });
-
-        let bgManager = new Background.BackgroundManager({ container: widget,
-                                                           monitorIndex,
-                                                           controlPosition: false,
-                                                           settingsSchema: SCREENSAVER_SCHEMA });
-
-        this._bgManagers.push(bgManager);
-
-        this._backgroundGroup.add_child(widget);
-    }
-
-    _updateBackgrounds() {
-        for (let i = 0; i < this._bgManagers.length; i++)
-            this._bgManagers[i].destroy();
-
-        this._bgManagers = [];
-        this._backgroundGroup.destroy_all_children();
-
-        for (let i = 0; i < Main.layoutManager.monitors.length; i++)
-            this._createBackground(i);
-    }
-
     _liftShield(velocity) {
         if (this._isLocked) {
             if (this._ensureUnlockDialog(true /* allowCancel */))

js/ui/unlockDialog.js

@@ -4,6 +4,7 @@
 const { AccountsService, Atk, Clutter, Gdm, Gio,
         GnomeDesktop, GLib, GObject, Meta, Shell, St } = imports.gi;
 
+const Background = imports.ui.background;
 const Layout = imports.ui.layout;
 const Main = imports.ui.main;
 const MessageTray = imports.ui.messageTray;
@@ -13,6 +14,8 @@ const AuthPrompt = imports.gdm.authPrompt;
 // The timeout before going back automatically to the lock screen (in seconds)
 const IDLE_TIMEOUT = 2 * 60;
 
+const SCREENSAVER_SCHEMA = 'org.gnome.desktop.screensaver';
+
 const SUMMARY_ICON_SIZE = 48;
 
 var NotificationsBox = GObject.registerClass({
@@ -333,13 +336,21 @@ var UnlockDialog = GObject.registerClass({
         super._init({
             accessible_role: Atk.Role.WINDOW,
             style_class: 'login-dialog',
-            layout_manager: new Clutter.BoxLayout(),
             visible: false,
         });
 
-        this.add_constraint(new Layout.MonitorConstraint({ primary: true }));
         parentActor.add_child(this);
 
+        // Background
+        this._backgroundGroup = new Clutter.Actor();
+        this.add_child(this._backgroundGroup);
+
+        this._bgManagers = [];
+
+        this._updateBackgrounds();
+        this._monitorsChangedId =
+            Main.layoutManager.connect('monitors-changed', this._updateBackgrounds.bind(this));
+
         this._userManager = AccountsService.UserManager.get_default();
         this._userName = GLib.get_user_name();
         this._user = this._userManager.get_user(this._userName);
@@ -350,6 +361,7 @@ var UnlockDialog = GObject.registerClass({
                                              x_expand: true,
                                              y_expand: true });
         this.add_child(this._promptBox);
+        this._promptBox.add_constraint(new Layout.MonitorConstraint({ primary: true }));
 
         this._clock = new Clock();
         this._promptBox.add_child(this._clock);
@@ -394,6 +406,39 @@ var UnlockDialog = GObject.registerClass({
         this.connect('destroy', this._onDestroy.bind(this));
     }
 
+    _createBackground(monitorIndex) {
+        let monitor = Main.layoutManager.monitors[monitorIndex];
+        let widget = new St.Widget({
+            style_class: 'screen-shield-background',
+            x: monitor.x,
+            y: monitor.y,
+            width: monitor.width,
+            height: monitor.height,
+        });
+
+        let bgManager = new Background.BackgroundManager({
+            container: widget,
+            monitorIndex,
+            controlPosition: false,
+            settingsSchema: SCREENSAVER_SCHEMA,
+        });
+
+        this._bgManagers.push(bgManager);
+
+        this._backgroundGroup.add_child(widget);
+    }
+
+    _updateBackgrounds() {
+        for (let i = 0; i < this._bgManagers.length; i++)
+            this._bgManagers[i].destroy();
+
+        this._bgManagers = [];
+        this._backgroundGroup.destroy_all_children();
+
+        for (let i = 0; i < Main.layoutManager.monitors.length; i++)
+            this._createBackground(i);
+    }
+
     _updateSensitivity(sensitive) {
         this._authPrompt.updateSensitivity(sensitive);
 
@@ -437,6 +482,11 @@ var UnlockDialog = GObject.registerClass({
             this._idleMonitor.remove_watch(this._idleWatchId);
             this._idleWatchId = 0;
         }
+
+        if (this._monitorsChangedId) {
+            Main.layoutManager.disconnect(this._monitorsChangedId);
+            delete this._monitorsChangedId;
+        }
     }
 
     cancel() {