Struct FinalizableHandle 

pub struct FinalizableHandle { /* private fields */ }

FinalizableHandle can be used as payload in super::Value::FinalizableHandle. Will be received in Dart as instance of FinalizableHandle. When the Dart instance gets garbage collected, the finalizer closure specified in `FinalizableHandle::new will be invoked.

FinalizableHandle must be created on main thread, but other methods are thread safe.

Implementations

impl FinalizableHandle

pub fn new<F: FnOnce() + 'static>( external_size: isize, isolate_id: IsolateId, finalizer: F, ) -> Self

Creates a new finalizable handle instance. Must be created on main thread and the finalizer will also be invoked on main thread.

If FinalizableHandle gets dropped the finalizer will not be executed. The finalizer is guaranteed to be executed even if the target isolate gets destroyed before it had chance to create dart weak persistent handle.

Arguments

• finalizer - closure that will be executed on main thread when the Dart object associated with this handle is garbage collected. The closure will not be invoked when this FinalizableHandle is dropped.

• external_size - hit to garbage collector about how much memory is taken by native object. Used when determining memory pressure.

pub fn is_attached(&self) -> bool

Whether this handle is attached to a Dart object. This will be false initially and becomes true once the Finalizable handle is send to Dart. false after the Dart counterpart gets garbage collected.

pub fn is_finalized(&self) -> bool

Whether the Dart object was already garbage collected finalized.

pub fn update_size(&self, size: isize)

Updates the external size. This is a hint to Dart garbage collector.

Trait Implementations

impl Debug for FinalizableHandle

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

Formats the value using the given formatter.

impl Drop for FinalizableHandle

fn drop(&mut self)

Executes the destructor for this type.

impl Hash for FinalizableHandle

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for FinalizableHandle

fn eq(&self, other: &FinalizableHandle) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for FinalizableHandle

fn partial_cmp(&self, other: &FinalizableHandle) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl Eq for FinalizableHandle

impl StructuralPartialEq for FinalizableHandle