* Add doc-test to test website code snippets Heavily inspired by tokio-rs/website repo. * Fix code snippets to pass doc tests Some code snippets are explicitly ignored and some are not run to avoid having to include dependencies for one liners. * Add website code snippet tests to CI * Fix CI * Remove doc-test from workspace * Exclude doc-test from workspace * Refactor code snippets and tests Code snippets can import types from doc_test crate i.e.: ```rust use doc_test::agents::EventBus; ``` This allows for moving some boilerplate away from the example and still checks that the code compiles correctly. Also some slight changes to some of the examples and the information about `ComponentLink` which is deprecated. * Move doc-test to packages * Rename doc-test crate to website-test The new name makes it more clear the purpose of this crate. * fix ci
17 KiB
| title | description |
|---|---|
| Elements | Both HTML and SVG elements are supported |
DOM nodes
There are many reasons why you might want to create or manage DOM nodes manually in Yew, such as when integrating with JS libraries that can cause conflicts with managed components.
Using web-sys, you can create DOM elements and convert them into a Node - which can then be
used as a Html value using VRef:
use yew::{
Component, Context, html, Html, utils::document,
web_sys::{Element, Node}
};
struct Comp;
impl Component for Comp {
type Message = ();
type Properties = ();
fn create(_ctx: &Context<Self>) -> Self {
Self
}
fn view(&self, _ctx: &Context<Self>) -> Html {
// Create a div element from the document
let div: Element = document().create_element("div").unwrap();
// Add content, classes etc.
div.set_inner_html("Hello, World!");
// Convert Element into a Node
let node: Node = div.into();
// Return that Node as a Html value
Html::VRef(node)
}
}
Dynamic tag names
When building a higher-order component you might find yourself in a situation where the element's tag name isn't static.
For example, you might have a Title component which can render anything from h1 to h6 depending on a level prop.
Instead of having to use a big match expression, Yew allows you to set the tag name dynamically
using @{name} where name can be any expression that returns a string.
use yew::html;
let level = 5;
let text = "Hello World!".to_owned();
html! {
<@{format!("h{}", level)} class="title">{ text }</@>
};
Boolean Attributes
Some content attributes (e.g checked, hidden, required) are called boolean attributes. In Yew, boolean attributes need to be set to a bool value:
use yew::html;
html! {
<div hidden=true>
{ "This div is hidden." }
</div>
};
This will result in HTML that's functionally equivalent to this:
<div hidden>This div is hidden.</div>
Setting a boolean attribute to false is equivalent to not using the attribute at all; values from boolean expressions can be used:
use yew::html;
let no = 1 + 1 != 2;
html! {
<div hidden={no}>
{ "This div is NOT hidden." }
</div>
};
This will result in the following HTML:
<div>This div is NOT hidden.</div>
Optional attributes for HTML elements
Most HTML attributes can use optional values (Some(x) or None). This allows us to omit the attribute if the attribute is marked as optional.
use yew::html;
let maybe_id = Some("foobar");
html! {
<div id={maybe_id}></div>
};
If the attribute is set to None, the attribute won't be set in the DOM.
Listeners
Listener attributes need to be passed a Callback which is a wrapper around a closure. How you create your callback depends on how you wish your app to react to a listener event:
use yew::{Component, Context, html, Html};
struct MyComponent;
enum Msg {
Click,
}
impl Component for MyComponent {
type Message = Msg;
type Properties = ();
fn create(_ctx: &Context<Self>) -> Self {
Self
}
fn update(&mut self, _ctx: &Context<Self>, msg: Self::Message) -> bool {
match msg {
Msg::Click => {
// Handle Click
}
};
true
}
fn view(&self, ctx: &Context<Self>) -> Html {
// Create a callback from a component link to handle it in a component
let click_callback = ctx.link().callback(|_| Msg::Click);
html! {
<button onclick={click_callback}>
{ "Click me!" }
</button>
}
}
}
use yew::{html, Component, Context, Html};
use yew_agent::{Dispatcher, Dispatched};
use website_test::agents::{MyWorker, WorkerMsg};
struct MyComponent {
worker: Dispatcher<MyWorker>,
}
impl Component for MyComponent {
type Message = WorkerMsg;
type Properties = ();
fn create(_ctx: &Context<Self>) -> Self {
MyComponent {
worker: MyWorker::dispatcher(),
}
}
fn update(&mut self, _ctx: &Context<Self>, msg: Self::Message) -> bool {
self.worker.send(msg);
false
}
fn view(&self, ctx: &Context<Self>) -> Html {
// Create a callback from a worker to handle it in another context
let click_callback = ctx.link().callback(|_| WorkerMsg::Process);
html! {
<button onclick={click_callback}>
{ "Click me!" }
</button>
}
}
}
use yew::{Callback, Context, Component, html, Html};
use weblog::console_log;
struct MyComponent;
impl Component for MyComponent {
type Message = ();
type Properties = ();
fn create(_ctx: &Context<Self>) -> Self {
MyComponent
}
fn view(&self, _ctx: &Context<Self>) -> Html {
// Create an ephemeral callback
let click_callback = Callback::from(|_| {
console_log!("clicked!");
});
html! {
<button onclick={click_callback}>
{ "Click me!" }
</button>
}
}
}
Event Types
:::tip
All the event types mentioned in the following table are re-exported under yew::events.
Using the types from yew::events makes it easier to ensure version compatibility than
if you were to manually include web-sys as a dependency in your crate because you won't
end up using a version which conflicts with the version that Yew specifies.
:::
| Event name | web_sys Event Type |
|---|---|
onabort |
Event |
onauxclick |
MouseEvent |
onblur |
FocusEvent |
oncancel |
Event |
oncanplay |
Event |
oncanplaythrough |
Event |
onchange |
Event |
onclick |
MouseEvent |
onclose |
Event |
oncontextmenu |
MouseEvent |
oncuechange |
Event |
ondblclick |
MouseEvent |
ondrag |
DragEvent |
ondragend |
DragEvent |
ondragenter |
DragEvent |
ondragexit |
DragEvent |
ondragleave |
DragEvent |
ondragover |
DragEvent |
ondragstart |
DragEvent |
ondrop |
DragEvent |
ondurationchange |
Event |
onemptied |
Event |
onended |
Event |
onerror |
Event |
onfocus |
FocusEvent |
onfocusin |
FocusEvent |
onfocusout |
FocusEvent |
onformdata |
Event |
oninput |
InputEvent |
oninvalid |
Event |
onkeydown |
KeyboardEvent |
onkeypress |
KeyboardEvent |
onkeyup |
KeyboardEvent |
onload |
Event |
onloadeddata |
Event |
onloadedmetadata |
Event |
onloadstart |
ProgressEvent |
onmousedown |
MouseEvent |
onmouseenter |
MouseEvent |
onmouseleave |
MouseEvent |
onmousemove |
MouseEvent |
onmouseout |
MouseEvent |
onmouseover |
MouseEvent |
onmouseup |
MouseEvent |
onpause |
Event |
onplay |
Event |
onplaying |
Event |
onprogress |
ProgressEvent |
onratechange |
Event |
onreset |
Event |
onresize |
Event |
onscroll |
Event |
onsecuritypolicyviolation |
Event |
onseeked |
Event |
onseeking |
Event |
onselect |
Event |
onslotchange |
Event |
onstalled |
Event |
onsubmit |
FocusEvent |
onsuspend |
Event |
ontimeupdate |
Event |
ontoggle |
Event |
onvolumechange |
Event |
onwaiting |
Event |
onwheel |
WheelEvent |
oncopy |
Event |
oncut |
Event |
onpaste |
Event |
onanimationcancel |
AnimationEvent |
onanimationend |
AnimationEvent |
onanimationiteration |
AnimationEvent |
onanimationstart |
AnimationEvent |
ongotpointercapture |
PointerEvent |
onloadend |
ProgressEvent |
onlostpointercapture |
PointerEvent |
onpointercancel |
PointerEvent |
onpointerdown |
PointerEvent |
onpointerenter |
PointerEvent |
onpointerleave |
PointerEvent |
onpointerlockchange |
Event |
onpointerlockerror |
Event |
onpointermove |
PointerEvent |
onpointerout |
PointerEvent |
onpointerover |
PointerEvent |
onpointerup |
PointerEvent |
onselectionchange |
Event |
onselectstart |
Event |
onshow |
Event |
ontouchcancel |
TouchEvent |
ontouchend |
TouchEvent |
ontouchmove |
TouchEvent |
ontouchstart |
TouchEvent |
ontransitioncancel |
TransitionEvent |
ontransitionend |
TransitionEvent |
ontransitionrun |
TransitionEvent |
ontransitionstart |
TransitionEvent |