/// A unique identifier for an element that can be inspected.#[derive(Debug, Eq, PartialEq, Hash, Clone)]pub struct InspectorElementId { /// Stable part of the ID. #[cfg(any(feature = "inspector", debug_assertions))] pub path: std::rc::Rc<InspectorElementPath>, /// Disambiguates elements that have the same path. #[cfg(any(feature = "inspector", debug_assertions))] pub instance_id: usize,} impl Into<InspectorElementId> for &InspectorElementId { fn into(self) -> InspectorElementId { self.clone() }} #[cfg(any(feature = "inspector", debug_assertions))]pub use conditional::*; #[cfg(any(feature = "inspector", debug_assertions))]mod conditional { use super::*; use crate::{AnyElement, App, Context, Empty, IntoElement, Render, Window}; use collections::{FxHashMap, TypeIdHashMap}; use std::any::{Any, TypeId}; /// `GlobalElementId` qualified by source location of element construction. #[derive(Debug, Eq, PartialEq, Hash)] pub struct InspectorElementPath { /// The path to the nearest ancestor element that has an `ElementId`. #[cfg(any(feature = "inspector", debug_assertions))] pub global_id: crate::GlobalElementId, /// Source location where this element was constructed. #[cfg(any(feature = "inspector", debug_assertions))] pub source_location: &'static std::panic::Location<'static>, } impl Clone for InspectorElementPath { fn clone(&self) -> Self { Self { global_id: self.global_id.clone(), source_location: self.source_location, } } } impl Into<InspectorElementPath> for &InspectorElementPath { fn into(self) -> InspectorElementPath { self.clone() } } /// Function set on `App` to render the inspector UI. pub type InspectorRenderer = Box<dyn Fn(&mut Inspector, &mut Window, &mut Context<Inspector>) -> AnyElement>; /// Manages inspector state - which element is currently selected and whether the inspector is /// in picking mode. pub struct Inspector { active_element: Option<InspectedElement>, pub(crate) pick_depth: Option<f32>, } struct InspectedElement { id: InspectorElementId, states: TypeIdHashMap<Box<dyn Any>>, } impl InspectedElement { fn new(id: InspectorElementId) -> Self { InspectedElement { id, states: Default::default(), } } } impl Inspector { pub(crate) fn new() -> Self { Self { active_element: None, pick_depth: Some(0.0), } } pub(crate) fn select(&mut self, id: InspectorElementId, window: &mut Window) { self.set_active_element_id(id, window); self.pick_depth = None; } pub(crate) fn hover(&mut self, id: InspectorElementId, window: &mut Window) { if self.is_picking() { let changed = self.set_active_element_id(id, window); if changed { self.pick_depth = Some(0.0); } } } pub(crate) fn set_active_element_id( &mut self, id: InspectorElementId, window: &mut Window, ) -> bool { let changed = Some(&id) != self.active_element_id(); if changed { self.active_element = Some(InspectedElement::new(id)); window.refresh(); } changed } /// ID of the currently hovered or selected element. pub fn active_element_id(&self) -> Option<&InspectorElementId> { self.active_element.as_ref().map(|e| &e.id) } pub(crate) fn with_active_element_state<T: 'static, R>( &mut self, window: &mut Window, f: impl FnOnce(&mut Option<T>, &mut Window) -> R, ) -> R { let Some(active_element) = &mut self.active_element else { return f(&mut None, window); }; let type_id = TypeId::of::<T>(); let mut inspector_state = active_element .states .remove(&type_id) .map(|state| *state.downcast().unwrap()); let result = f(&mut inspector_state, window); if let Some(inspector_state) = inspector_state { active_element .states .insert(type_id, Box::new(inspector_state)); } result } /// Starts element picking mode, allowing the user to select elements by clicking. pub fn start_picking(&mut self) { self.pick_depth = Some(0.0); } /// Returns whether the inspector is currently in picking mode. pub fn is_picking(&self) -> bool { self.pick_depth.is_some() } /// Renders elements for all registered inspector states of the active inspector element. pub fn render_inspector_states( &mut self, window: &mut Window, cx: &mut Context<Self>, ) -> Vec<AnyElement> { let mut elements = Vec::new(); if let Some(active_element) = self.active_element.take() { for (type_id, state) in &active_element.states { if let Some(render_inspector) = cx .inspector_element_registry .renderers_by_type_id .remove(type_id) { let mut element = (render_inspector)( active_element.id.clone(), state.as_ref(), window, cx, ); elements.push(element); cx.inspector_element_registry .renderers_by_type_id .insert(*type_id, render_inspector); } } self.active_element = Some(active_element); } elements } } impl Render for Inspector { fn render(&mut self, window: &mut Window, cx: &mut Context<Self>) -> impl IntoElement { if let Some(inspector_renderer) = cx.inspector_renderer.take() { let result = inspector_renderer(self, window, cx); cx.inspector_renderer = Some(inspector_renderer); result } else { Empty.into_any_element() } } } #[derive(Default)] pub(crate) struct InspectorElementRegistry { renderers_by_type_id: FxHashMap< TypeId, Box<dyn Fn(InspectorElementId, &dyn Any, &mut Window, &mut App) -> AnyElement>, >, } impl InspectorElementRegistry { pub fn register<T: 'static, R: IntoElement>( &mut self, f: impl 'static + Fn(InspectorElementId, &T, &mut Window, &mut App) -> R, ) { self.renderers_by_type_id.insert( TypeId::of::<T>(), Box::new(move |id, value, window, cx| { let value = value.downcast_ref().unwrap(); f(id, value, window, cx).into_any_element() }), ); } }} /// Provides definitions used by `#[derive_inspector_reflection]`.#[cfg(any(feature = "inspector", debug_assertions))]pub mod inspector_reflection { use std::any::Any; /// Reification of a function that has the signature `fn some_fn(T) -> T`. Provides the name, /// documentation, and ability to invoke the function. #[derive(Clone, Copy)] pub struct FunctionReflection<T> { /// The name of the function pub name: &'static str, /// The method pub function: fn(Box<dyn Any>) -> Box<dyn Any>, /// Documentation for the function pub documentation: Option<&'static str>, /// `PhantomData` for the type of the argument and result pub _type: std::marker::PhantomData<T>, } impl<T: 'static> FunctionReflection<T> { /// Invoke this method on a value and return the result. pub fn invoke(&self, value: T) -> T { let boxed = Box::new(value) as Box<dyn Any>; let result = (self.function)(boxed); *result .downcast::<T>() .expect("Type mismatch in reflection invoke") } }}
/// A unique identifier for an element that can be inspected.
#[derive(Debug, Eq, PartialEq, Hash, Clone)]
pub struct InspectorElementId {
/// Stable part of the ID.
#[cfg(any(feature = "inspector", debug_assertions))]
pub path: std::rc::Rc<InspectorElementPath>,
/// Disambiguates elements that have the same path.
#[cfg(any(feature = "inspector", debug_assertions))]
pub instance_id: usize,
}
impl Into<InspectorElementId> for &InspectorElementId {
fn into(self) -> InspectorElementId {
self.clone()
}
}
#[cfg(any(feature = "inspector", debug_assertions))]
pub use conditional::*;
#[cfg(any(feature = "inspector", debug_assertions))]
mod conditional {
use super::*;
use crate::{AnyElement, App, Context, Empty, IntoElement, Render, Window};
use collections::{FxHashMap, TypeIdHashMap};
use std::any::{Any, TypeId};
/// `GlobalElementId` qualified by source location of element construction.
#[derive(Debug, Eq, PartialEq, Hash)]
pub struct InspectorElementPath {
/// The path to the nearest ancestor element that has an `ElementId`.
#[cfg(any(feature = "inspector", debug_assertions))]
pub global_id: crate::GlobalElementId,
/// Source location where this element was constructed.
#[cfg(any(feature = "inspector", debug_assertions))]
pub source_location: &'static std::panic::Location<'static>,
}
impl Clone for InspectorElementPath {
fn clone(&self) -> Self {
Self {
global_id: self.global_id.clone(),
source_location: self.source_location,
}
}
}
impl Into<InspectorElementPath> for &InspectorElementPath {
fn into(self) -> InspectorElementPath {
self.clone()
}
}
/// Function set on `App` to render the inspector UI.
pub type InspectorRenderer =
Box<dyn Fn(&mut Inspector, &mut Window, &mut Context<Inspector>) -> AnyElement>;
/// Manages inspector state - which element is currently selected and whether the inspector is
/// in picking mode.
pub struct Inspector {
active_element: Option<InspectedElement>,
pub(crate) pick_depth: Option<f32>,
}
struct InspectedElement {
id: InspectorElementId,
states: TypeIdHashMap<Box<dyn Any>>,
}
impl InspectedElement {
fn new(id: InspectorElementId) -> Self {
InspectedElement {
id,
states: Default::default(),
}
}
}
impl Inspector {
pub(crate) fn new() -> Self {
Self {
active_element: None,
pick_depth: Some(0.0),
}
}
pub(crate) fn select(&mut self, id: InspectorElementId, window: &mut Window) {
self.set_active_element_id(id, window);
self.pick_depth = None;
}
pub(crate) fn hover(&mut self, id: InspectorElementId, window: &mut Window) {
if self.is_picking() {
let changed = self.set_active_element_id(id, window);
if changed {
self.pick_depth = Some(0.0);
}
}
}
pub(crate) fn set_active_element_id(
&mut self,
id: InspectorElementId,
window: &mut Window,
) -> bool {
let changed = Some(&id) != self.active_element_id();
if changed {
self.active_element = Some(InspectedElement::new(id));
window.refresh();
}
changed
}
/// ID of the currently hovered or selected element.
pub fn active_element_id(&self) -> Option<&InspectorElementId> {
self.active_element.as_ref().map(|e| &e.id)
}
pub(crate) fn with_active_element_state<T: 'static, R>(
&mut self,
window: &mut Window,
f: impl FnOnce(&mut Option<T>, &mut Window) -> R,
) -> R {
let Some(active_element) = &mut self.active_element else {
return f(&mut None, window);
};
let type_id = TypeId::of::<T>();
let mut inspector_state = active_element
.states
.remove(&type_id)
.map(|state| *state.downcast().unwrap());
let result = f(&mut inspector_state, window);
if let Some(inspector_state) = inspector_state {
active_element
.states
.insert(type_id, Box::new(inspector_state));
}
result
}
/// Starts element picking mode, allowing the user to select elements by clicking.
pub fn start_picking(&mut self) {
self.pick_depth = Some(0.0);
}
/// Returns whether the inspector is currently in picking mode.
pub fn is_picking(&self) -> bool {
self.pick_depth.is_some()
}
/// Renders elements for all registered inspector states of the active inspector element.
pub fn render_inspector_states(
&mut self,
window: &mut Window,
cx: &mut Context<Self>,
) -> Vec<AnyElement> {
let mut elements = Vec::new();
if let Some(active_element) = self.active_element.take() {
for (type_id, state) in &active_element.states {
if let Some(render_inspector) = cx
.inspector_element_registry
.renderers_by_type_id
.remove(type_id)
{
let mut element = (render_inspector)(
active_element.id.clone(),
state.as_ref(),
window,
cx,
);
elements.push(element);
cx.inspector_element_registry
.renderers_by_type_id
.insert(*type_id, render_inspector);
}
}
self.active_element = Some(active_element);
}
elements
}
}
impl Render for Inspector {
fn render(&mut self, window: &mut Window, cx: &mut Context<Self>) -> impl IntoElement {
if let Some(inspector_renderer) = cx.inspector_renderer.take() {
let result = inspector_renderer(self, window, cx);
cx.inspector_renderer = Some(inspector_renderer);
result
} else {
Empty.into_any_element()
}
}
}
#[derive(Default)]
pub(crate) struct InspectorElementRegistry {
renderers_by_type_id: FxHashMap<
TypeId,
Box<dyn Fn(InspectorElementId, &dyn Any, &mut Window, &mut App) -> AnyElement>,
>,
}
impl InspectorElementRegistry {
pub fn register<T: 'static, R: IntoElement>(
&mut self,
f: impl 'static + Fn(InspectorElementId, &T, &mut Window, &mut App) -> R,
) {
self.renderers_by_type_id.insert(
TypeId::of::<T>(),
Box::new(move |id, value, window, cx| {
let value = value.downcast_ref().unwrap();
f(id, value, window, cx).into_any_element()
}),
);
}
}
}
/// Provides definitions used by `#[derive_inspector_reflection]`.
#[cfg(any(feature = "inspector", debug_assertions))]
pub mod inspector_reflection {
use std::any::Any;
/// Reification of a function that has the signature `fn some_fn(T) -> T`. Provides the name,
/// documentation, and ability to invoke the function.
#[derive(Clone, Copy)]
pub struct FunctionReflection<T> {
/// The name of the function
pub name: &'static str,
/// The method
pub function: fn(Box<dyn Any>) -> Box<dyn Any>,
/// Documentation for the function
pub documentation: Option<&'static str>,
/// `PhantomData` for the type of the argument and result
pub _type: std::marker::PhantomData<T>,
}
impl<T: 'static> FunctionReflection<T> {
/// Invoke this method on a value and return the result.
pub fn invoke(&self, value: T) -> T {
let boxed = Box::new(value) as Box<dyn Any>;
let result = (self.function)(boxed);
*result
.downcast::<T>()
.expect("Type mismatch in reflection invoke")
}
}
}