image_window: Don't rely on root existing

This fixes a single case of root being access from the control hide
animation. Apparently it's possible that the widget is unparented from
the window and unmaped but not yet unrefed?

Fixes #473

news.d/48.1/fixes-dont-crash-on-window-close

@@ -0,0 +1 @@
+Crash when closing the window, probably in the exact moment when the animnation for hiding controls starts.

src/util/root.rs

@@ -24,12 +24,28 @@ pub trait ParentWindow: WidgetExt {
         let result = self.root().and_downcast();
 
         if result.is_none() {
-            log::error!("Couldn't find LpWindow for {self:?}");
+            log::error!(
+                "Couldn't find LpWindow for {self:?}. mapped={}",
+                self.is_mapped()
+            );
         }
 
         result.unwrap()
     }
 
+    fn try_window(&self) -> Option<LpWindow> {
+        let result = self.root().and_downcast();
+
+        if result.is_none() {
+            log::debug!(
+                "Couldn't find LpWindow for {self:?}. mapped={}",
+                self.is_mapped()
+            );
+        }
+
+        result
+    }
+
     fn edit_window(&self) -> LpEditWindow {
         let parent = self.parent().unwrap();
 

src/widgets/image_window/controls.rs

@@ -1,4 +1,4 @@
-// Copyright (c) 2023-2024 Sophie Herold
+// Copyright (c) 2023-2025 Sophie Herold
 //
 // This program is free software: you can redistribute it and/or modify
 // it under the terms of the GNU General Public License as published by
@@ -26,21 +26,21 @@ impl LpImageWindow {
     /// Also changes headerbar transparency if it flat and hides/shows cursor on
     /// fullscreen
     fn set_control_opacity(&self, opacity: f64, hiding: bool) {
-        let window = self.window();
+        if let Some(window) = self.try_window() {
+            self.image_view().controls_box_start().set_opacity(opacity);
+            self.image_view().controls_box_end().set_opacity(opacity);
 
-        self.image_view().controls_box_start().set_opacity(opacity);
+            if self.is_headerbar_flat() && window.is_fullscreen() {
-        self.image_view().controls_box_end().set_opacity(opacity);
+                self.headerbar().set_opacity(opacity);
+            } else {
+                self.headerbar().set_opacity(1.);
+            }
 
-        if self.is_headerbar_flat() && window.is_fullscreen() {
+            if window.is_fullscreen() && hiding && opacity < 0.9 {
-            self.headerbar().set_opacity(opacity);
+                self.set_cursor(gdk::Cursor::from_name("none", None).as_ref());
-        } else {
+            } else {
-            self.headerbar().set_opacity(1.);
+                self.set_cursor(None);
-        }
+            }
-
-        if window.is_fullscreen() && hiding && opacity < 0.9 {
-            self.set_cursor(gdk::Cursor::from_name("none", None).as_ref());
-        } else {
-            self.set_cursor(None);
         }
     }