Dynamic::try_lock

Plus other minor changes.

CHANGELOG.md

@@ -215,6 +215,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - `Delimiter` is a new widget that is similar to html's `hr` tag.
 - `List` is a new widget that creates lists similar to HTML's `ol` and `ul`
   tags.
+- `Dynamic::try_lock()` is a panic-free version of `Dynamic::lock()`.
 
 [plotters]: https://github.com/plotters-rs/plotters
 

src/context.rs

@@ -1363,7 +1363,7 @@ pub(crate) mod sealed {
         fn inner_invalidate_when_changed(&self, handle: WindowHandle, id: WidgetId);
     }
 
-    #[derive(Default, Clone)]
+    #[derive(Debug, Default, Clone)]
     pub struct InvalidationStatus {
         refresh_sent: Arc<AtomicBool>,
         invalidated: Arc<Mutex<Set<WidgetId>>>,

src/value.rs

@@ -1089,6 +1089,23 @@ impl<T> Dynamic<T> {
         self.lock_inner()
     }
 
+    /// Returns an exclusive reference to the contents of this dynamic.
+    ///
+    /// This call will block until all other guards for this dynamic have been
+    /// dropped.
+    ///
+    /// # Errors
+    ///
+    /// Returns an error if the current thread already holds a lock to this
+    /// dynamic.
+    pub fn try_lock(&self) -> Result<DynamicGuard<'_, T>, DeadlockError> {
+        Ok(DynamicGuard {
+            guard: self.0.state()?,
+            accessed_mut: false,
+            prevent_notifications: false,
+        })
+    }
+
     fn lock_inner<const READONLY: bool>(&self) -> DynamicGuard<'_, T, READONLY> {
         DynamicGuard {
             guard: self.0.state().expect("deadlocked"),

src/widget.rs

@@ -2129,6 +2129,18 @@ impl Dynamic<WidgetList> {
         self.clone().into_layers()
     }
 
+    /// Returns `self` as an unordered [`List`].
+    #[must_use]
+    pub fn into_list(self) -> List {
+        List::new(self)
+    }
+
+    /// Returns `self` as an unordered [`List`].
+    #[must_use]
+    pub fn to_list(self) -> List {
+        self.clone().into_list()
+    }
+
     /// Returns a [`Wrap`] that lays the children out horizontally, wrapping
     /// into additional rows as needed.
     #[must_use]

src/widgets/expand.rs

@@ -9,7 +9,7 @@ use crate::ConstraintLimit;
 ///
 /// Some parent widgets support weighting children when there is more than one
 /// [`Expand`]ed widget.
-#[derive(Debug)]
+#[derive(Debug, Clone)]
 pub struct Expand {
     kind: ExpandKind,
     child: WidgetRef,

src/widgets/list.rs

@@ -476,7 +476,8 @@ fn build_grid_widgets(style: &ListStyle, children: &WidgetList) -> GridWidgets<2
                         .list_indicator(index.wrapping_add(1))
                         .unwrap_or_default(),
                 )
-                .align_right(),
+                .align_right()
+                .align_top(),
                 child.clone().align_left().make_widget(),
             )
         })

src/window.rs

@@ -1964,7 +1964,7 @@ pub(crate) mod sealed {
         pub on_closed: Option<OnceCallback>,
     }
 
-    #[derive(Clone)]
+    #[derive(Debug, Clone)]
     pub enum WindowCommand {
         Redraw,
         RequestClose,
@@ -2079,7 +2079,7 @@ fn default_family(query: Family<'_>) -> Option<FamilyOwned> {
 }
 
 /// A handle to an open Cushy window.
-#[derive(Clone)]
+#[derive(Debug, Clone)]
 pub struct WindowHandle {
     inner: InnerWindowHandle,
     pub(crate) redraw_status: InvalidationStatus,
@@ -2140,7 +2140,7 @@ impl Hash for WindowHandle {
     }
 }
 
-#[derive(Clone)]
+#[derive(Debug, Clone)]
 enum InnerWindowHandle {
     Pending(Arc<PendingWindowHandle>),
     Known(kludgine::app::WindowHandle<WindowCommand>),
@@ -2233,7 +2233,7 @@ impl PendingWindow {
     }
 }
 
-#[derive(Default)]
+#[derive(Debug, Default)]
 struct PendingWindowHandle {
     handle: OnceLock<kludgine::app::WindowHandle<WindowCommand>>,
     commands: Mutex<Vec<WindowCommand>>,