Struct Subscription 

pub struct Subscription { /* private fields */ }

A handle to a callback that GPUI calls until the handle is dropped.

Methods such as Context::observe, Context::subscribe and App::observe return a Subscription. Dropping it cancels the callback. Keep it in a field to tie the callback to the lifetime of the entity that owns the field. Call Subscription::detach to keep the callback registered without holding the handle.

Implementations

impl Subscription

pub fn new(unsubscribe: impl 'static + FnOnce()) -> Self

Creates a subscription that runs unsubscribe when it’s dropped.

Use it to give your own resource the same drop-to-cancel behavior as the subscriptions that GPUI returns.

Examples

let cleaned_up = Rc::new(Cell::new(false));

let subscription = Subscription::new({
    let cleaned_up = cleaned_up.clone();
    move || cleaned_up.set(true)
});
assert!(!cleaned_up.get());

drop(subscription);
assert!(cleaned_up.get());

pub fn detach(self)

Forgets the cancellation handle and leaves the callback registered.

A callback created by GPUI may still remove itself when an entity it depends on is released. Detaching does not run the unsubscribe callback supplied to Subscription::new.

pub fn join(subscription_a: Self, subscription_b: Self) -> Self

Combines two subscriptions into one cancellation handle.

Dropping the result cancels both subscriptions. Calling Subscription::detach on the result detaches both.

Trait Implementations

impl Debug for Subscription

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Drop for Subscription

fn drop(&mut self)

Executes the destructor for this type.

fn pin_drop(self: Pin<&mut Self>)

🔬This is a nightly-only experimental API. (pin_ergonomics)

Execute the destructor for this type, but different to Drop::drop, it requires self to be pinned.