widget::Container requests paint when Key has changed (#1881)

Fixes #1880 Co-authored-by: Colin Rofls <colin@cmyr.net>
linebender · Jul 27, 2021 · 8bd8805 · 8bd8805
1 parent 85c71ca
commit 8bd8805
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Showing 2 changed files with 13 additions and 2 deletions.
diff --git a/druid/src/widget/container.rs b/druid/src/widget/container.rs
@@ -156,9 +156,9 @@ impl<T: Data> Widget<T> for Container<T> {
         skip(self, ctx, old_data, data, env)
     )]
     fn update(&mut self, ctx: &mut UpdateCtx, old_data: &T, data: &T, env: &Env) {
-        if let Some(BackgroundBrush::Painter(p)) = self.background.as_mut() {
+        if let Some(brush) = self.background.as_mut() {
             trace_span!("update background").in_scope(|| {
-                p.update(ctx, old_data, data, env);
+                brush.update(ctx, old_data, data, env);
             });
         }
         self.inner.update(ctx, data, env);

diff --git a/druid/src/widget/painter.rs b/druid/src/widget/painter.rs
@@ -107,6 +107,17 @@ impl<T> Painter<T> {
 }
 
 impl<T: Data> BackgroundBrush<T> {
+    /// Request paint if the BackgroundBrush changed.
+    pub fn update(&mut self, ctx: &mut UpdateCtx, old_data: &T, data: &T, env: &Env) {
+        match self {
+            Self::ColorKey(key) if ctx.env_key_changed(key) => {
+                ctx.request_paint();
+            }
+            Self::Painter(p) => p.update(ctx, old_data, data, env),
+            _ => (),
+        }
+    }
+
     /// Draw this `BackgroundBrush` into a provided [`PaintCtx`].
     ///
     /// [`PaintCtx`]: ../struct.PaintCtx.html