use dioxus_native_core::exports::shipyard::Component; use dioxus_native_core::node_ref::*; use dioxus_native_core::prelude::*; use dioxus_native_core::real_dom::NodeTypeMut; use dioxus_native_core_macro::partial_derive_state; struct FontSize(f64); // All states need to derive Component #[derive(Default, Debug, Copy, Clone, Component)] struct Size(f64, f64); #[derive(Default, Debug, Copy, Clone, Component)] struct X; impl FromAnyValue for X { fn from_any_value(_: &dyn std::any::Any) -> Self { X } } /// Derive some of the boilerplate for the State implementation #[partial_derive_state] impl State for Size { type ParentDependencies = (); // The size of the current node depends on the size of its children type ChildDependencies = (Self,); type NodeDependencies = (); // Size only cares about the width, height, and text parts of the current node const NODE_MASK: NodeMaskBuilder<'static> = NodeMaskBuilder::new() // Get access to the width and height attributes .with_attrs(AttributeMaskBuilder::Some(&["width", "height"])) // Get access to the text of the node .with_text(); fn update<'a>( &mut self, node_view: NodeView, _node: ::ElementBorrowed<'a>, _parent: Option<::ElementBorrowed<'a>>, children: Vec<::ElementBorrowed<'a>>, context: &SendAnyMap, ) -> bool { let font_size = context.get::().unwrap().0; let mut width; let mut height; if let Some(text) = node_view.text() { // if the node has text, use the text to size our object width = text.len() as f64 * font_size; height = font_size; } else { // otherwise, the size is the maximum size of the children width = children .iter() .map(|(item,)| item.0) .reduce(|accum, item| if accum >= item { accum } else { item }) .unwrap_or(0.0); height = children .iter() .map(|(item,)| item.1) .reduce(|accum, item| if accum >= item { accum } else { item }) .unwrap_or(0.0); } // if the node contains a width or height attribute it overrides the other size for a in node_view.attributes().into_iter().flatten() { match &*a.attribute.name { "width" => width = a.value.as_float().unwrap(), "height" => height = a.value.as_float().unwrap(), // because Size only depends on the width and height, no other attributes will be passed to the member _ => panic!(), } } // to determine what other parts of the dom need to be updated we return a boolean that marks if this member changed let changed = (width != self.0) || (height != self.1); *self = Self(width, height); changed } } #[derive(Debug, Clone, Copy, PartialEq, Default, Component)] struct TextColor { r: u8, g: u8, b: u8, } #[partial_derive_state] impl State for TextColor { // TextColor depends on the TextColor part of the parent type ParentDependencies = (Self,); type ChildDependencies = (); type NodeDependencies = (); // TextColor only cares about the color attribute of the current node const NODE_MASK: NodeMaskBuilder<'static> = // Get access to the color attribute NodeMaskBuilder::new().with_attrs(AttributeMaskBuilder::Some(&["color"])); fn update<'a>( &mut self, node_view: NodeView, _node: ::ElementBorrowed<'a>, parent: Option<::ElementBorrowed<'a>>, _children: Vec<::ElementBorrowed<'a>>, _context: &SendAnyMap, ) -> bool { // TextColor only depends on the color tag, so getting the first tag is equivilent to looking through all tags let new = match node_view .attributes() .and_then(|mut attrs| attrs.next()) .and_then(|attr| attr.value.as_text()) { // if there is a color tag, translate it Some("red") => TextColor { r: 255, g: 0, b: 0 }, Some("green") => TextColor { r: 0, g: 255, b: 0 }, Some("blue") => TextColor { r: 0, g: 0, b: 255 }, Some(color) => panic!("unknown color {color}"), // otherwise check if the node has a parent and inherit that color None => match parent { Some((parent,)) => *parent, None => Self::default(), }, }; // check if the member has changed let changed = new != *self; *self = new; changed } } #[derive(Debug, Clone, Copy, PartialEq, Default, Component)] struct Border(bool); #[partial_derive_state] impl State for Border { // TextColor depends on the TextColor part of the parent type ParentDependencies = (Self,); type ChildDependencies = (); type NodeDependencies = (); // Border does not depended on any other member in the current node const NODE_MASK: NodeMaskBuilder<'static> = // Get access to the border attribute NodeMaskBuilder::new().with_attrs(AttributeMaskBuilder::Some(&["border"])); fn update<'a>( &mut self, node_view: NodeView, _node: ::ElementBorrowed<'a>, _parent: Option<::ElementBorrowed<'a>>, _children: Vec<::ElementBorrowed<'a>>, _context: &SendAnyMap, ) -> bool { // check if the node contians a border attribute let new = Self( node_view .attributes() .and_then(|mut attrs| attrs.next().map(|a| a.attribute.name == "border")) .is_some(), ); // check if the member has changed let changed = new != *self; *self = new; changed } } fn main() -> Result<(), Box> { let mut rdom: RealDom = RealDom::new([ Border::to_type_erased(), TextColor::to_type_erased(), Size::to_type_erased(), ]); let mut count = 0; // intial render let text_id = rdom.create_node(format!("Count: {count}")).id(); let mut root = rdom.get_mut(rdom.root_id()).unwrap(); // set the color to red if let NodeTypeMut::Element(mut element) = root.node_type_mut() { element.set_attribute(("color", "style"), "red".to_string()); } root.add_child(text_id); let mut ctx = SendAnyMap::new(); // set the font size to 3.3 ctx.insert(FontSize(3.3)); // update the State for nodes in the real_dom tree let _to_rerender = rdom.update_state(ctx); // we need to run the vdom in a async runtime tokio::runtime::Builder::new_current_thread() .enable_all() .build()? .block_on(async { loop { // update the count count += 1; let mut text = rdom.get_mut(text_id).unwrap(); if let NodeTypeMut::Text(mut text) = text.node_type_mut() { *text = format!("Count: {count}"); } let mut ctx = SendAnyMap::new(); ctx.insert(FontSize(3.3)); let _to_rerender = rdom.update_state(ctx); // render... rdom.traverse_depth_first(|node| { let indent = " ".repeat(node.height() as usize); let color = *node.get::().unwrap(); let size = *node.get::().unwrap(); let border = *node.get::().unwrap(); let id = node.id(); println!("{indent}{id:?} {color:?} {size:?} {border:?}"); }); // wait 1 second tokio::time::sleep(std::time::Duration::from_secs(1)).await; } }) }