DioxusLabs/dioxus · error

Global signal with key {:?} is not of the expected type. Key

Error message

Global signal with key {:?} is not of the expected type. Keys are {:?}

What it means

A global signal looked up by GlobalKey stored a value of a different type than requested. The downcast_ref::<Signal<T>>() failed because the key was first registered with another T; global signal keys are per-type and reusing one with a different type triggers this panic.

Source

Thrown at packages/signals/src/global/mod.rs:269

            column: key.column(),
            index: 0,
        }
    }
}

impl From<&'static Location<'static>> for GlobalKey<'static> {
    fn from(key: &'static Location<'static>) -> Self {
        Self::new(key)
    }
}

impl GlobalLazyContext {
    /// Get a signal with the given string key
    /// The key will be converted to a UUID with the appropriate internal namespace
    pub fn get_signal_with_key<T: 'static>(&self, key: GlobalKey) -> Option<Signal<T>> {
        self.map.borrow().get(&key).map(|f| {
            *f.downcast_ref::<Signal<T>>().unwrap_or_else(|| {
                panic!(
                    "Global signal with key {:?} is not of the expected type. Keys are {:?}",
                    key,
                    self.map.borrow().keys()
                )
            })
        })
    }

    #[doc(hidden)]
    /// Clear all global signals of a given type.
    pub fn clear<T: 'static>(&self) {
        self.map.borrow_mut().retain(|_k, v| !v.is::<T>());
    }
}

/// Get the global context for signals
pub fn get_global_context() -> GlobalLazyContext {
    let rt = Runtime::current();

View on GitHub (pinned to 24f6a829df)

Solutions

1. A GlobalSignal key was reused with a different type. Use one consistent type per global signal key, or use a distinct key.

When it happens

Trigger: Thrown at packages/signals/src/global/mod.rs:269 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of DioxusLabs/dioxus@24f6a829df (2026-08-23). Data as JSON: /api/errors/1f9376461b9af739. Report an issue: GitHub.