Add DragAndDrop::take_payload

crates/egui/src/drag_and_drop.rs

@@ -67,6 +67,23 @@ impl DragAndDrop {
         })
     }
 
+    /// Retrieve and clear the payload, if any.
+    ///
+    /// Returns `None` if there is no payload, or if it is not of the requested type.
+    ///
+    /// Returns `Some` both during a drag and on the frame the pointer is released
+    /// (if there is a payload).
+    pub fn take_payload<Payload>(ctx: &Context) -> Option<Arc<Payload>>
+    where
+        Payload: Any + Send + Sync,
+    {
+        ctx.data_mut(|data| {
+            let state = data.get_temp_mut_or_default::<Self>(Id::NULL);
+            let payload = state.payload.take()?;
+            payload.downcast().ok()
+        })
+    }
+
     /// Are we carrying a payload of the given type?
     ///
     /// Returns `true` both during a drag and on the frame the pointer is released

crates/egui/src/response.rs

@@ -366,7 +366,7 @@ impl Response {
         // NOTE: we use `response.contains_pointer` here instead of `hovered`, because
         // `hovered` is always false when another widget is being dragged.
         if self.contains_pointer() && self.ctx.input(|i| i.pointer.any_released()) {
-            crate::DragAndDrop::payload::<Payload>(&self.ctx)
+            crate::DragAndDrop::take_payload::<Payload>(&self.ctx)
         } else {
             None
         }