Reactivity
Declare state
import { createSignal } from "solid-js";
export default function Name() {
const [name] = createSignal("John");
return <h1>Hello {name()}</h1>;
}
Qwik
import { component$, useSignal } from "@builder.io/qwik";
export const Name = component$(() => {
const name = useSignal("John");
return <h1>Hello {name.value}</h1>;
});
Update state
import { createSignal } from "solid-js";
export default function Name() {
const [name, setName] = createSignal("John");
setName("Jane");
return <h1>Hello {name()}</h1>;
}
Qwik
import { component$, useTask$, useSignal } from "@builder.io/qwik";
export const Name = component$(() => {
const name = useSignal("John");
useTask$(() => {
name.value = "Jane";
});
return <h1>Hello {name.value}</h1>;
});
Computed state
import { createSignal } from "solid-js";
export default function DoubleCount() {
const [count] = createSignal(10);
const doubleCount = () => count() * 2;
return <div>{doubleCount()}</div>;
}
Qwik
import { component$, useSignal, useComputed$ } from "@builder.io/qwik";
export const DoubleCount = component$(() => {
const count = useSignal(10);
const doubleCount = useComputed$(() => count.value * 2);
return <div>{doubleCount.value}</div>;
});
Templating
Minimal template
Styling
import "./style.css";
export default function CssStyle() {
return (
<>
<h1 class="title">I am red</h1>
<button style={{ "font-size": "10rem" }}>I am a button</button>
</>
);
}
Qwik
import { component$, useStyles$ } from "@builder.io/qwik";
export const App = component$(() => {
useStyles$(`
.title {
color: red;
}
`);
return (
<>
<h1 class="title">I am red</h1>
<button style={{ "font-size": "10rem" }}>I am a button</button>
</>
);
});
Loop
import { For } from "solid-js";
export default function Colors() {
const colors = ["red", "green", "blue"];
return (
<ul>
<For each={colors}>{(color) => <li>{color}</li>}</For>
</ul>
);
}
Qwik
import { component$ } from "@builder.io/qwik";
export const Colors = component$(() => {
const colors = ["red", "green", "blue"];
return (
<ul>
{colors.map((color) => (
<li key={color}>{color}</li>
))}
</ul>
);
});
Event click
import { createSignal } from "solid-js";
export default function Counter() {
const [count, setCount] = createSignal(0);
function incrementCount() {
setCount(count() + 1);
}
return (
<>
<p>Counter: {count()}</p>
<button onClick={incrementCount}>+1</button>
</>
);
}
Qwik
import { component$, useSignal, $ } from "@builder.io/qwik";
export const Counter = component$(() => {
const count = useSignal(0);
const incrementCount = $(() => {
count.value++;
});
return (
<>
<p>Counter: {count.value}</p>
<button onClick$={incrementCount}>Increment</button>
</>
);
});
Dom ref
import { onMount } from "solid-js";
export default function InputFocused() {
let inputElement;
onMount(() => inputElement.focus());
return <input ref={inputElement} type="text" />;
}
Qwik
import { component$, useVisibleTask$, useSignal } from "@builder.io/qwik";
export const InputFocused = component$(() => {
const inputElement = useSignal<HTMLInputElement>();
useVisibleTask$(({ track }) => {
const el = track(inputElement);
el?.focus();
});
return <input type="text" ref={inputElement} />;
});
Conditional
import { createSignal, Switch, Match } from "solid-js";
const TRAFFIC_LIGHTS = ["red", "orange", "green"];
export default function TrafficLight() {
const [lightIndex, setLightIndex] = createSignal(0);
const light = () => TRAFFIC_LIGHTS[lightIndex()];
function nextLight() {
setLightIndex((lightIndex() + 1) % TRAFFIC_LIGHTS.length);
}
return (
<>
<button onClick={nextLight}>Next light</button>
<p>Light is: {light()}</p>
<p>
You must
<Switch>
<Match when={light() === "red"}>
<span>STOP</span>
</Match>
<Match when={light() === "orange"}>
<span>SLOW DOWN</span>
</Match>
<Match when={light() === "green"}>
<span>GO</span>
</Match>
</Switch>
</p>
</>
);
}
Qwik
import { $, component$, useComputed$, useSignal } from "@builder.io/qwik";
export const TRAFFIC_LIGHTS = ["red", "orange", "green"];
export const TrafficLight = component$(() => {
const lightIndex = useSignal(0);
const light = useComputed$(() => TRAFFIC_LIGHTS[lightIndex.value]);
const nextLight = $(() => {
lightIndex.value = (lightIndex.value + 1) % TRAFFIC_LIGHTS.length;
});
return (
<>
<button onClick$={nextLight}>Next light</button>
<p>Light is: {light.value}</p>
<p>
You must {light.value === "red" && <span>STOP</span>}
{light.value === "orange" && <span>SLOW DOWN</span>}
{light.value === "green" && <span>GO</span>}
</p>
</>
);
});
Lifecycle
On mount
import { createSignal, onMount } from "solid-js";
export default function PageTitle() {
const [pageTitle, setPageTitle] = createSignal("");
onMount(() => {
setPageTitle(document.title);
});
return <p>Page title: {pageTitle()}</p>;
}
Qwik
import { component$, useVisibleTask$, useStore } from "@builder.io/qwik";
export const App = component$(() => {
const store = useStore({
pageTitle: "",
});
useVisibleTask$(() => {
store.pageTitle = document.title;
});
return <p>Page title: {store.pageTitle}</p>;
});
On unmount
import { createSignal, onCleanup } from "solid-js";
export default function Time() {
const [time, setTime] = createSignal(new Date().toLocaleTimeString());
const timer = setInterval(() => {
setTime(new Date().toLocaleTimeString());
}, 1000);
onCleanup(() => clearInterval(timer));
return <p>Current time: {time()}</p>;
}
Qwik
import { component$, useVisibleTask$, useStore } from "@builder.io/qwik";
export const App = component$(() => {
const store = useStore({
time: new Date().toLocaleTimeString(),
});
useVisibleTask$(({ cleanup }) => {
const timer = setInterval(() => {
store.time = new Date().toLocaleTimeString();
}, 1000);
cleanup(() => clearInterval(timer));
});
return <p>Current time: {store.time}</p>;
});
Component composition
Props
import UserProfile from "./UserProfile.jsx";
export default function App() {
return (
<UserProfile
name="John"
age={20}
favouriteColors={["green", "blue", "red"]}
isAvailable
/>
);
}
Qwik
import { component$ } from "@builder.io/qwik";
import UserProfile from "./UserProfile";
const App = component$(() => {
return (
<UserProfile
name="John"
age={20}
favouriteColors={["green", "blue", "red"]}
isAvailable
/>
);
});
export default App;
Emit to parent
import { createSignal } from "solid-js";
import AnswerButton from "./AnswerButton.jsx";
export default function App() {
const [isHappy, setIsHappy] = createSignal(true);
function onAnswerNo() {
setIsHappy(false);
}
function onAnswerYes() {
setIsHappy(true);
}
return (
<>
<p>Are you happy?</p>
<AnswerButton onYes={onAnswerYes} onNo={onAnswerNo} />
<p style={{ "font-size": "50px" }}>{isHappy() ? "😀" : "😥"}</p>
</>
);
}
Qwik
import { $, component$, useStore } from "@builder.io/qwik";
import AnswerButton from "./AnswerButton";
const App = component$(() => {
const store = useStore({
isHappy: true,
});
const onAnswerNo = $(() => {
store.isHappy = false;
});
const onAnswerYes = $(() => {
store.isHappy = true;
});
return (
<>
<p>Are you happy?</p>
<AnswerButton onYes$={onAnswerYes} onNo$={onAnswerNo} />
<p style={{ fontSize: 50 }}>{store.isHappy ? "😀" : "😥"}</p>
</>
);
});
export default App;
Slot
Slot fallback
import FunnyButton from "./FunnyButton.jsx";
export default function App() {
return (
<>
<FunnyButton />
<FunnyButton>I got content!</FunnyButton>
</>
);
}
Qwik
import FunnyButton from "./FunnyButton";
export default function App() {
return (
<>
<FunnyButton />
<FunnyButton>Click me!</FunnyButton>
</>
);
}
Context
import { createSignal } from "solid-js";
import { UserContext } from "./UserContext";
import UserProfile from "./UserProfile";
export default function App() {
const [user, setUser] = createSignal({
id: 1,
username: "unicorn42",
email: "[email protected]",
});
function updateUsername(newUsername) {
setUser({ ...user(), username: newUsername });
}
return (
<>
<h1>Welcome back, {user().username}</h1>
<UserContext.Provider value={[user, updateUsername]}>
<UserProfile />
</UserContext.Provider>
</>
);
}
Qwik
import {
component$,
useStore,
useContextProvider,
createContext,
$,
} from "@builder.io/qwik";
import UserProfile from "./UserProfile";
export const UserContext = createContext("user-context");
const App = component$(() => {
const user = useStore({
id: 1,
username: "unicorn42",
email: "[email protected]",
});
const updateUsername = $((newUsername) => {
user.username = newUsername;
});
useContextProvider(UserContext, { user, updateUsername });
return (
<>
<h1>Welcome back, {user.username}</h1>
<UserProfile />
</>
);
});
export default App;
Form input
Input text
import { createSignal } from "solid-js";
export default function InputHello() {
const [text, setText] = createSignal("Hello world");
function handleChange(event) {
setText(event.target.value);
}
return (
<>
<p>{text()}</p>
<input value={text()} onInput={handleChange} />
</>
);
}
Qwik
import { component$, useSignal } from "@builder.io/qwik";
const InputHello = component$(() => {
const text = useSignal("");
return (
<>
<p>{text.value}</p>
<input bind:value={text} />
</>
);
});
export default InputHello;
Checkbox
import { createSignal } from "solid-js";
export default function IsAvailable() {
const [isAvailable, setIsAvailable] = createSignal(false);
function handleChange() {
setIsAvailable((previousValue) => !previousValue);
}
return (
<>
<input
id="is-available"
type="checkbox"
checked={isAvailable()}
onChange={handleChange}
/>
<label for="is-available">Is available</label>
</>
);
}
Qwik
import { component$, useSignal } from "@builder.io/qwik";
const IsAvailable = component$(() => {
const isAvailable = useSignal(false);
return (
<>
<input id="is-available" type="checkbox" bind:checked={isAvailable} />
<label for="is-available">Is available</label>
</>
);
});
export default IsAvailable;
Radio
import { createSignal } from "solid-js";
export default function PickPill() {
const [picked, setPicked] = createSignal("red");
function handleChange(event) {
setPicked(event.target.value);
}
return (
<>
<div>Picked: {picked()}</div>
<input
id="blue-pill"
checked={picked() === "blue"}
type="radio"
value="blue"
onChange={handleChange}
/>
<label for="blue-pill">Blue pill</label>
<input
id="red-pill"
checked={picked() === "red"}
type="radio"
value="red"
onChange={handleChange}
/>
<label for="red-pill">Red pill</label>
</>
);
}
Qwik
import { component$, useSignal } from "@builder.io/qwik";
const PickPill = component$(() => {
const pickedColor = useSignal("red");
return (
<>
<div>Picked: {pickedColor.value}</div>
<input
id="blue-pill"
type="radio"
bind:value={pickedColor}
checked={pickedColor.value === "blue"}
value="blue"
/>
<label for="blue-pill">Blue pill</label>
<input
id="red-pill"
type="radio"
checked={pickedColor.value === "red"}
bind:value={pickedColor}
value="red"
/>
<label for="red-pill">Red pill</label>
</>
);
});
export default PickPill;
Select
import { createSignal, For } from "solid-js";
const colors = [
{ id: 1, text: "red" },
{ id: 2, text: "blue" },
{ id: 3, text: "green" },
{ id: 4, text: "gray", isDisabled: true },
];
export default function ColorSelect() {
const [selectedColorId, setSelectedColorId] = createSignal(2);
function handleChange(event) {
setSelectedColorId(event.target.value);
}
return (
<select value={selectedColorId()} onChange={handleChange}>
<For each={colors}>
{(color) => (
<option value={color.id} disabled={color.isDisabled}>
{color.text}
</option>
)}
</For>
</select>
);
}
Qwik
import { component$, useSignal } from "@builder.io/qwik";
export const colors = [
{ id: 1, text: "red" },
{ id: 2, text: "blue" },
{ id: 3, text: "green" },
{ id: 4, text: "gray", isDisabled: true },
];
const ColorSelect = component$(() => {
const selectedColorId = useSignal("2");
return (
<select bind:value={selectedColorId}>
{colors.map((color) => (
<option
key={color.id}
value={color.id}
disabled={color.isDisabled}
selected={`${color.id}` === selectedColorId.value}
>
{color.text}
</option>
))}
</select>
);
});
export default ColorSelect;
Webapp features
Render app
Fetch data
import { createResource, For, Switch, Match } from "solid-js";
async function fetchUsers() {
return (await fetch("https://randomuser.me/api/?results=3")).json();
}
export default function App() {
const [data] = createResource(fetchUsers);
const users = () => data()?.results;
return (
<Switch>
<Match when={data.loading}>
<p>Fetching users...</p>
</Match>
<Match when={data.error}>
<p>An error occurred while fetching users</p>
</Match>
<Match when={users()}>
<ul>
<For each={users()}>
{(user) => (
<li>
<img src={user.picture.thumbnail} alt="user" />
<p>
{user.name.first} {user.name.last}
</p>
</li>
)}
</For>
</ul>
</Match>
</Switch>
);
}
Qwik
import { component$, useResource$, Resource } from "@builder.io/qwik";
type UsersResponse = {
results: {
picture: {
thumbnail: string;
};
name: {
first: string;
last: string;
};
}[];
};
export async function fetchUsers() {
return (await fetch("https://randomuser.me/api/?results=3")).json();
}
export const App = component$(() => {
const data = useResource$<UsersResponse>(fetchUsers);
return (
<Resource
value={data}
onPending={() => <p>Fetching users...</p>}
onRejected={() => <p>An error occurred while fetching users</p>}
onResolved={({ results: users }) => (
<ul>
{users.map((user) => (
<li>
<img src={user.picture.thumbnail} alt="user" />
<p>
{user.name.first} {user.name.last}
</p>
</li>
))}
</ul>
)}
/>
);
});