Struct ChangeTracker 

pub struct ChangeTracker { /* private fields */ }

A change tracker is used to run a callback when a property value changes.

The Change Tracker must be initialized with the Self::init method.

When the property changes, the ChangeTracker is added to a thread local list, and the notify callback is called when the Self::run_change_handlers() method is called

Implementations

impl ChangeTracker

pub fn init<Data, T: Default + PartialEq, EF: Fn(&Data) -> T, NF: Fn(&Data, &T)>( &self, data: Data, eval_fn: EF, notify_fn: NF, )

Initialize the change tracker with the given data and callbacks.

The data is any struct that is going to be passed to the functor. The eval_fn is a function that queries and return the property. And the notify_fn is the callback run if the property is changed

pub fn init_delayed<Data, T: Default + PartialEq, EF: Fn(&Data) -> T, NF: Fn(&Data, &T)>( &self, data: Data, eval_fn: EF, notify_fn: NF, )

Initialize the change tracker with the given data and callbacks.

Same as Self::init, but the first eval function is called in a future evaluation of the event loop. This means that the change tracker will consider the value as default initialized, and the eval function will be called the firs ttime if the initial value is not equal to the default constructed value.

pub fn clear(&self)

Clear the change tracker. No notify function will be called after this.

pub fn run_change_handlers()

Run all the change handler that were queued.

Trait Implementations

impl Debug for ChangeTracker

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

Formats the value using the given formatter.

impl Default for ChangeTracker

fn default() -> Self

Returns the “default value” for a type.

impl Drop for ChangeTracker

fn drop(&mut self)

Executes the destructor for this type.