Reactivity
Declare state
Update state
<script setup>
import { ref } from "vue";
const name = ref("John");
name.value = "Jane";
</script>
<template>
<h1>Hello {{ name }}</h1>
</template>
Computed state
<script setup>
import { ref, computed } from "vue";
const count = ref(10);
const doubleCount = computed(() => count.value * 2);
</script>
<template>
<div>{{ doubleCount }}</div>
</template>
Templating
Minimal template
Styling
<template>
<h1 class="title">I am red</h1>
<button style="font-size: 10rem">I am a button</button>
</template>
<style scoped>
.title {
color: red;
}
</style>
Loop
<script setup>
const colors = ["red", "green", "blue"];
</script>
<template>
<ul>
<li v-for="color in colors" :key="color">
{{ color }}
</li>
</ul>
</template>
Event click
<script setup>
import { ref } from "vue";
const count = ref(0);
function incrementCount() {
count.value++;
}
</script>
<template>
<p>Counter: {{ count }}</p>
<button @click="incrementCount">+1</button>
</template>
Dom ref
<script setup>
import { useTemplateRef, onMounted } from "vue";
const inputElement = useTemplateRef("inputElement");
onMounted(() => {
inputElement.value.focus();
});
</script>
<template>
<input ref="inputElement" />
</template>
Conditional
<script setup>
import { ref, computed } from "vue";
const TRAFFIC_LIGHTS = ["red", "orange", "green"];
const lightIndex = ref(0);
const light = computed(() => TRAFFIC_LIGHTS[lightIndex.value]);
function nextLight() {
lightIndex.value = (lightIndex.value + 1) % TRAFFIC_LIGHTS.length;
}
</script>
<template>
<button @click="nextLight">Next light</button>
<p>Light is: {{ light }}</p>
<p>
You must
<span v-if="light === 'red'">STOP</span>
<span v-else-if="light === 'orange'">SLOW DOWN</span>
<span v-else-if="light === 'green'">GO</span>
</p>
</template>
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>
</>
);
}
Lifecycle
On mount
<script setup>
import { ref, onMounted } from "vue";
const pageTitle = ref("");
onMounted(() => {
pageTitle.value = document.title;
});
</script>
<template>
<p>Page title: {{ pageTitle }}</p>
</template>
On unmount
<script setup>
import { ref, onUnmounted } from "vue";
const time = ref(new Date().toLocaleTimeString());
const timer = setInterval(() => {
time.value = new Date().toLocaleTimeString();
}, 1000);
onUnmounted(() => {
clearInterval(timer);
});
</script>
<template>
<p>Current time: {{ time }}</p>
</template>
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>;
}
Component composition
Props
<script setup>
import UserProfile from "./UserProfile.vue";
</script>
<template>
<UserProfile
name="John"
:age="20"
:favourite-colors="['green', 'blue', 'red']"
is-available
/>
</template>
Emit to parent
<script setup>
import { ref } from "vue";
import AnswerButton from "./AnswerButton.vue";
let isHappy = ref(true);
function onAnswerNo() {
isHappy.value = false;
}
function onAnswerYes() {
isHappy.value = true;
}
</script>
<template>
<p>Are you happy?</p>
<AnswerButton @yes="onAnswerYes" @no="onAnswerNo" />
<p style="font-size: 50px">
{{ isHappy ? "😀" : "😥" }}
</p>
</template>
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>
</>
);
}
Slot
Slot fallback
<script setup>
import FunnyButton from "./FunnyButton.vue";
</script>
<template>
<FunnyButton />
<FunnyButton> I got content! </FunnyButton>
</template>
Context
<script setup>
import { ref, provide } from "vue";
import UserProfile from "./UserProfile.vue";
const user = ref({
id: 1,
username: "unicorn42",
email: "[email protected]",
});
function updateUsername(username) {
user.value.username = username;
}
provide("user", { user, updateUsername });
</script>
<template>
<h1>Welcome back, {{ user.username }}</h1>
<UserProfile />
</template>
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>
</>
);
}
Form input
Input text
<script setup>
import { ref } from "vue";
const text = ref("Hello World");
</script>
<template>
<p>{{ text }}</p>
<input v-model="text" />
</template>
Checkbox
<script setup>
import { ref } from "vue";
const isAvailable = ref(true);
</script>
<template>
<input id="is-available" v-model="isAvailable" type="checkbox" />
<label for="is-available">Is available</label>
</template>
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>
</>
);
}
Radio
<script setup>
import { ref } from "vue";
const picked = ref("red");
</script>
<template>
<div>Picked: {{ picked }}</div>
<input id="blue-pill" v-model="picked" type="radio" value="blue" />
<label for="blue-pill">Blue pill</label>
<input id="red-pill" v-model="picked" type="radio" value="red" />
<label for="red-pill">Red pill</label>
</template>
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>
</>
);
}
Select
<script setup>
import { ref } from "vue";
const selectedColorId = ref(2);
const colors = [
{ id: 1, text: "red" },
{ id: 2, text: "blue" },
{ id: 3, text: "green" },
{ id: 4, text: "gray", isDisabled: true },
];
</script>
<template>
<select v-model="selectedColorId">
<option
v-for="color in colors"
:key="color.id"
:value="color.id"
:disabled="color.isDisabled"
>
{{ color.text }}
</option>
</select>
</template>
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>
);
}
Webapp features
Render app
Fetch data
<script setup>
import useFetchUsers from "./useFetchUsers";
const { isLoading, error, data: users } = useFetchUsers();
</script>
<template>
<p v-if="isLoading">Fetching users...</p>
<p v-else-if="error">An error ocurred while fetching users</p>
<ul v-else-if="users">
<li v-for="user in users" :key="user.login.uuid">
<img :src="user.picture.thumbnail" alt="user" />
<p>
{{ user.name.first }}
{{ user.name.last }}
</p>
</li>
</ul>
</template>
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>
);
}