feat: add better use_state for fermi

This commit is contained in:
Jonathan Kelley 2022-04-05 21:36:48 -04:00
parent dfc69c0905
commit 4518b6bc8c
3 changed files with 424 additions and 2 deletions

View file

@ -0,0 +1,422 @@
use crate::{use_atom_root, AtomId, AtomRoot, Readable, Writable};
use dioxus_core::{ScopeId, ScopeState};
use std::{
cell::{RefCell, RefMut},
fmt::{Debug, Display},
marker::PhantomData,
ops::{Add, Div, Mul, Not, Sub},
rc::Rc,
sync::Arc,
};
/// Store state between component renders.
///
/// ## Dioxus equivalent of AtomState, designed for Rust
///
/// The Dioxus version of `AtomState` for state management inside components. It allows you to ergonomically store and
/// modify state between component renders. When the state is updated, the component will re-render.
///
///
/// ```ignore
/// static COUNT: Atom<u32> = |_| 0;
///
/// fn Example(cx: Scope) -> Element {
/// let mut count = use_atom_state(&cx, COUNT);
///
/// cx.render(rsx! {
/// div {
/// h1 { "Count: {count}" }
/// button { onclick: move |_| count += 1, "Increment" }
/// button { onclick: move |_| count -= 1, "Decrement" }
/// }
/// ))
/// }
/// ```
pub fn use_atom_state<'a, T: 'static>(cx: &'a ScopeState, f: impl Writable<T>) -> &'a AtomState<T> {
let root = crate::use_atom_root(cx);
let inner = cx.use_hook(|_| AtomState {
value: None,
root: root.clone(),
scope_id: cx.scope_id(),
id: f.unique_id(),
});
inner.value = Some(inner.root.register(f, cx.scope_id()));
inner
}
pub struct AtomState<V: 'static> {
root: Rc<AtomRoot>,
id: AtomId,
scope_id: ScopeId,
value: Option<Rc<V>>,
}
impl<V> Drop for AtomState<V> {
fn drop(&mut self) {
self.root.unsubscribe(self.id, self.scope_id)
}
}
impl<T: 'static> AtomState<T> {
/// Set the state to a new value.
pub fn set(&self, new: T) {
self.root.set(self.id, new)
}
/// Get the current value of the state by cloning its container Rc.
///
/// This is useful when you are dealing with state in async contexts but need
/// to know the current value. You are not given a reference to the state.
///
/// # Examples
/// An async context might need to know the current value:
///
/// ```rust, ignore
/// fn component(cx: Scope) -> Element {
/// let count = use_state(&cx, || 0);
/// cx.spawn({
/// let set_count = count.to_owned();
/// async move {
/// let current = set_count.current();
/// }
/// })
/// }
/// ```
#[must_use]
pub fn current(&self) -> Rc<T> {
self.value.as_ref().unwrap().clone()
}
/// Get the `setter` function directly without the `AtomState` wrapper.
///
/// This is useful for passing the setter function to other components.
///
/// However, for most cases, calling `to_owned` o`AtomState`te is the
/// preferred way to get "anoth`set_state`tate handle.
///
///
/// # Examples
/// A component might require an `Rc<dyn Fn(T)>` as an input to set a value.
///
/// ```rust, ignore
/// fn component(cx: Scope) -> Element {
/// let value = use_state(&cx, || 0);
///
/// rsx!{
/// Component {
/// handler: value.setter()
/// }
/// }
/// }
/// ```
#[must_use]
pub fn setter(&self) -> Rc<dyn Fn(T)> {
let root = self.root.clone();
let id = self.id;
Rc::new(move |new_val| root.set(id, new_val))
}
/// Set the state to a new value, using the current state value as a reference.
///
/// This is similar to passing a closure to React's `set_value` function.
///
/// # Examples
///
/// Basic usage:
/// ```rust
/// # use dioxus_core::prelude::*;
/// # use dioxus_hooks::*;
/// fn component(cx: Scope) -> Element {
/// let value = use_state(&cx, || 0);
///
/// // to increment the value
/// value.modify(|v| v + 1);
///
/// // usage in async
/// cx.spawn({
/// let value = value.to_owned();
/// async move {
/// value.modify(|v| v + 1);
/// }
/// });
///
/// # todo!()
/// }
/// ```
pub fn modify(&self, f: impl FnOnce(&T) -> T) {
self.root.clone().set(self.id, {
let current = self.value.as_ref().unwrap();
f(current.as_ref())
});
}
/// Get the value of the state when this handle was created.
///
/// This method is useful when you want an `Rc` around the data to cheaply
/// pass it around your app.
///
/// ## Warning
///
/// This will return a stale value if used within async contexts.
///
/// Try `current` to get the real current value of the state.
///
/// ## Example
///
/// ```rust, ignore
/// # use dioxus_core::prelude::*;
/// # use dioxus_hooks::*;
/// fn component(cx: Scope) -> Element {
/// let value = use_state(&cx, || 0);
///
/// let as_rc = value.get();
/// assert_eq!(as_rc.as_ref(), &0);
///
/// # todo!()
/// }
/// ```
#[must_use]
pub fn get(&self) -> &T {
self.value.as_ref().unwrap()
}
#[must_use]
pub fn get_rc(&self) -> &Rc<T> {
self.value.as_ref().unwrap()
}
/// Mark all consumers of this atom to re-render
///
/// ```rust, ignore
/// fn component(cx: Scope) -> Element {
/// let count = use_state(&cx, || 0);
/// cx.spawn({
/// let count = count.to_owned();
/// async move {
/// // for the component to re-render
/// count.needs_update();
/// }
/// })
/// }
/// ```
pub fn needs_update(&self) {
self.root.force_update(self.id)
}
}
impl<T: Clone> AtomState<T> {
/// Get a mutable handle to the value by calling `ToOwned::to_owned` on the
/// current value.
///
/// This is essentially cloning the underlying value and then setting it,
/// giving you a mutable handle in the process. This method is intended for
/// types that are cheaply cloneable.
///
/// If you are comfortable dealing with `RefMut`, then you can use `make_mut` to get
/// the underlying slot. However, be careful with `RefMut` since you might panic
/// if the `RefCell` is left open.
///
/// # Examples
///
/// ```
/// let val = use_state(&cx, || 0);
///
/// val.with_mut(|v| *v = 1);
/// ```
pub fn with_mut(&self, apply: impl FnOnce(&mut T)) {
let mut new_val = self.value.as_ref().unwrap().as_ref().to_owned();
apply(&mut new_val);
self.set(new_val);
}
/// Get a mutable handle to the value by calling `ToOwned::to_owned` on the
/// current value.
///
/// This is essentially cloning the underlying value and then setting it,
/// giving you a mutable handle in the process. This method is intended for
/// types that are cheaply cloneable.
///
/// # Warning
/// Be careful with `RefMut` since you might panic if the `RefCell` is left open!
///
/// # Examples
///
/// ```
/// let val = use_state(&cx, || 0);
///
/// *val.make_mut() += 1;
/// ```
#[must_use]
pub fn make_mut(&self) -> RefMut<T> {
todo!("make mut not support for atom values yet")
// let mut slot = self.value.as_ref().unwrap();
// self.needs_update();
// if Rc::strong_count(&*slot) > 0 {
// *slot = Rc::new(slot.as_ref().to_owned());
// }
// RefMut::map(slot, |rc| Rc::get_mut(rc).expect("the hard count to be 0"))
}
/// Convert this handle to a tuple of the value and the handle itself.
#[must_use]
pub fn split(&self) -> (&T, &Self) {
(self.value.as_ref().unwrap(), self)
}
}
impl<T: 'static> Clone for AtomState<T> {
fn clone(&self) -> Self {
AtomState {
root: self.root.clone(),
id: self.id,
scope_id: self.scope_id,
value: self.value.clone(),
}
}
}
impl<'a, T: 'static + Display> std::fmt::Display for AtomState<T> {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
write!(f, "{}", self.value.as_ref().unwrap())
}
}
impl<'a, T: std::fmt::Binary> std::fmt::Binary for AtomState<T> {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
write!(f, "{:b}", self.value.as_ref().unwrap().as_ref())
}
}
impl<T: PartialEq> PartialEq<T> for AtomState<T> {
fn eq(&self, other: &T) -> bool {
self.value.as_ref().unwrap().as_ref() == other
}
}
// todo: this but for more interesting conrete types
impl PartialEq<bool> for &AtomState<bool> {
fn eq(&self, other: &bool) -> bool {
self.value.as_ref().unwrap().as_ref() == other
}
}
impl<T: PartialEq> PartialEq<AtomState<T>> for AtomState<T> {
fn eq(&self, other: &AtomState<T>) -> bool {
Rc::ptr_eq(self.value.as_ref().unwrap(), other.value.as_ref().unwrap())
}
}
impl<T: Debug> Debug for AtomState<T> {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
write!(f, "{:?}", self.value.as_ref().unwrap())
}
}
impl<'a, T> std::ops::Deref for AtomState<T> {
type Target = T;
fn deref(&self) -> &Self::Target {
self.value.as_ref().unwrap().as_ref()
}
}
impl<T: Not + Copy> std::ops::Not for &AtomState<T> {
type Output = <T as std::ops::Not>::Output;
fn not(self) -> Self::Output {
self.value.as_ref().unwrap().not()
}
}
impl<T: Not + Copy> std::ops::Not for AtomState<T> {
type Output = <T as std::ops::Not>::Output;
fn not(self) -> Self::Output {
self.value.as_ref().unwrap().not()
}
}
impl<T: std::ops::Add + Copy> std::ops::Add<T> for &AtomState<T> {
type Output = <T as std::ops::Add>::Output;
fn add(self, other: T) -> Self::Output {
*self.value.as_ref().unwrap().as_ref() + other
}
}
impl<T: std::ops::Sub + Copy> std::ops::Sub<T> for &AtomState<T> {
type Output = <T as std::ops::Sub>::Output;
fn sub(self, other: T) -> Self::Output {
*self.value.as_ref().unwrap().as_ref() - other
}
}
impl<T: std::ops::Div + Copy> std::ops::Div<T> for &AtomState<T> {
type Output = <T as std::ops::Div>::Output;
fn div(self, other: T) -> Self::Output {
*self.value.as_ref().unwrap().as_ref() / other
}
}
impl<T: std::ops::Mul + Copy> std::ops::Mul<T> for &AtomState<T> {
type Output = <T as std::ops::Mul>::Output;
fn mul(self, other: T) -> Self::Output {
*self.value.as_ref().unwrap().as_ref() * other
}
}
impl<T: Add<Output = T> + Copy> std::ops::AddAssign<T> for &AtomState<T> {
fn add_assign(&mut self, rhs: T) {
self.set((*self.current()) + rhs);
}
}
impl<T: Sub<Output = T> + Copy> std::ops::SubAssign<T> for &AtomState<T> {
fn sub_assign(&mut self, rhs: T) {
self.set((*self.current()) - rhs);
}
}
impl<T: Mul<Output = T> + Copy> std::ops::MulAssign<T> for &AtomState<T> {
fn mul_assign(&mut self, rhs: T) {
self.set((*self.current()) * rhs);
}
}
impl<T: Div<Output = T> + Copy> std::ops::DivAssign<T> for &AtomState<T> {
fn div_assign(&mut self, rhs: T) {
self.set((*self.current()) / rhs);
}
}
impl<T: Add<Output = T> + Copy> std::ops::AddAssign<T> for AtomState<T> {
fn add_assign(&mut self, rhs: T) {
self.set((*self.current()) + rhs);
}
}
impl<T: Sub<Output = T> + Copy> std::ops::SubAssign<T> for AtomState<T> {
fn sub_assign(&mut self, rhs: T) {
self.set((*self.current()) - rhs);
}
}
impl<T: Mul<Output = T> + Copy> std::ops::MulAssign<T> for AtomState<T> {
fn mul_assign(&mut self, rhs: T) {
self.set((*self.current()) * rhs);
}
}
impl<T: Div<Output = T> + Copy> std::ops::DivAssign<T> for AtomState<T> {
fn div_assign(&mut self, rhs: T) {
self.set((*self.current()) / rhs);
}
}

View file

@ -30,11 +30,13 @@ pub mod hooks {
mod init_atom_root;
mod read;
mod set;
mod state;
pub use atom_ref::*;
pub use atom_root::*;
pub use init_atom_root::*;
pub use read::*;
pub use set::*;
pub use state::*;
}
/// All Atoms are `Readable` - they support reading their value.

View file

@ -39,8 +39,6 @@ impl AtomRoot {
}
pub fn register<V: 'static>(&self, f: impl Readable<V>, scope: ScopeId) -> Rc<V> {
log::trace!("registering atom {:?}", f.unique_id());
let mut atoms = self.atoms.borrow_mut();
// initialize the value if it's not already initialized