trait based event system

packages/html/src/events/transition.rs

@@ -1,12 +1,103 @@
 use dioxus_core::Event;
 
 pub type TransitionEvent = Event<TransitionData>;
-#[cfg_attr(feature = "serialize", derive(serde::Serialize, serde::Deserialize))]
-#[derive(Debug, Clone, PartialEq)]
+
 pub struct TransitionData {
-    pub property_name: String,
-    pub pseudo_element: String,
-    pub elapsed_time: f32,
+    inner: Box<dyn HasTransitionData>,
+}
+
+impl<E: HasTransitionData> From<E> for TransitionData {
+    fn from(e: E) -> Self {
+        Self { inner: Box::new(e) }
+    }
+}
+
+impl std::fmt::Debug for TransitionData {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.debug_struct("TransitionData")
+            .field("property_name", &self.inner.property_name())
+            .field("pseudo_element", &self.inner.pseudo_element())
+            .field("elapsed_time", &self.inner.elapsed_time())
+            .finish()
+    }
+}
+
+impl PartialEq for TransitionData {
+    fn eq(&self, other: &Self) -> bool {
+        self.inner.property_name() == other.inner.property_name()
+            && self.inner.pseudo_element() == other.inner.pseudo_element()
+            && self.inner.elapsed_time() == other.inner.elapsed_time()
+    }
+}
+
+impl TransitionData {
+    /// Downcast this event to a concrete event type
+    pub fn downcast<T: 'static>(&self) -> Option<&T> {
+        self.inner.as_any().downcast_ref::<T>()
+    }
+}
+
+#[cfg(feature = "serialize")]
+#[derive(serde::Serialize, serde::Deserialize)]
+struct SerializedTransitionData {
+    property_name: String,
+    pseudo_element: String,
+    elapsed_time: f32,
+}
+
+#[cfg(feature = "serialize")]
+impl From<&TransitionData> for SerializedTransitionData {
+    fn from(data: &TransitionData) -> Self {
+        Self {
+            property_name: data.inner.property_name(),
+            pseudo_element: data.inner.pseudo_element(),
+            elapsed_time: data.inner.elapsed_time(),
+        }
+    }
+}
+
+#[cfg(feature = "serialize")]
+impl HasTransitionData for SerializedTransitionData {
+    fn property_name(&self) -> String {
+        self.property_name.clone()
+    }
+
+    fn pseudo_element(&self) -> String {
+        self.pseudo_element.clone()
+    }
+
+    fn elapsed_time(&self) -> f32 {
+        self.elapsed_time
+    }
+
+    fn as_any(&self) -> &dyn std::any::Any {
+        self
+    }
+}
+
+#[cfg(feature = "serialize")]
+impl serde::Serialize for TransitionData {
+    fn serialize<S: serde::Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error> {
+        SerializedTransitionData::from(self).serialize(serializer)
+    }
+}
+
+#[cfg(feature = "serialize")]
+impl<'de> serde::Deserialize<'de> for TransitionData {
+    fn deserialize<D: serde::Deserializer<'de>>(deserializer: D) -> Result<Self, D::Error> {
+        let data = SerializedTransitionData::deserialize(deserializer)?;
+        Ok(Self {
+            inner: Box::new(data),
+        })
+    }
+}
+
+pub trait HasTransitionData: std::any::Any {
+    fn property_name(&self) -> String;
+    fn pseudo_element(&self) -> String;
+    fn elapsed_time(&self) -> f32;
+    /// return self as Any
+    fn as_any(&self) -> &dyn std::any::Any;
 }
 
 impl_event! {