关于 lit-and-vscode-extensions
这是一篇面向开发者的教程,介绍如何用 Lit Web Component 构建 VSCode 扩展,涵盖 Webview 界面、消息通信和 TypeScript 扩展命令。
主要功能
- 01配置 Lit 和 TypeScript 项目
- 02创建 Lit Web Component
- 03通过 Webview 消息通信
- 04注册扩展命令
适用场景
- 01构建基于 Lit 的 VSCode 扩展界面
- 02将 Webview 组件连接到扩展逻辑
安装
复制下面的命令,在终端中运行。
npx skills add https:/ / github.com/ rodydavis/ skills --skill lit-and-vscode-extensions安装后在 Claude Code 中输入/lit-and-vscode-extensions确认已加载。
详细介绍
Lit 和 VSCode 扩展
本文将介绍如何设置 Lit Web 组件,并使用它创建 VSCode 扩展。
TLDR 你可以在此处找到最终源码。
先决条件
- Vscode
- Node >= 16
- Typescript
开始使用
我们可以先在终端中导航到项目所在位置,然后运行以下命令:
npm init @vitejs/app --template lit-ts
接着输入项目名称 lit-vscode-extension,然后在 vscode 中打开项目并安装依赖项:
cd lit-vscode-extension
npm i -D @types/node
code .
使用以下内容更新 vite.config.ts:
import { defineConfig } from "vite";
import { resolve } from "path";
export default defineConfig({
base: "/lit-vscode-extension/",
build: {
outDir: "build",
rollupOptions: {
external: /^vscode/,
input: {
main: resolve(__dirname, "index.html"),
},
output: {
entryFileNames: "[name].js",
},
},
},
});
打开 package.json,并使用以下内容更新:
{
"name": "lit-vscode-extension",
"description": "Lit VSCode Extension Example",
"version": "0.0.1",
"publisher": "rodydavis",
"private": true,
"license": "MIT",
"repository": {
"type": "git",
"url": "https://github.com/rodydavis/lit-vscode-extension"
},
"engines": {
"vscode": "^1.47.0"
},
"categories": [
"Other"
],
"activationEvents": [
"onCommand:lit.start",
"onCommand:lit.reset",
"onWebviewPanel:lit"
],
"main": "./build/extension.js",
"contributes": {
"commands": [
{
"command": "lit.start",
"title": "Open Plugin",
"category": "lit"
},
{
"command": "lit.reset",
"title": "Reset",
"category": "lit"
}
]
},
"scripts": {
"dev": "vite",
"build": "tsc && vite build",
"ext": "tsc src/extension.ts --outdir build --skipLibCheck --module commonjs",
"compile": "npm run build && npm run ext",
"serve": "vite preview"
},
"dependencies": {
"lit": "^2.0.0-rc.2"
},
"devDependencies": {
"@types/node": "^15.12.4",
"@types/vscode": "^1.57.0",
"typescript": "^4.2.3",
"vite": "^2.3.5"
}
}
更新 package.json 后,运行 npm i。
模板
打开 index.html,并使用以下内容更新:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<link rel="icon" type="image/svg+xml" href="/src/favicon.svg" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<title>Lit Example</title>
<script type="module" src="/src/my-element.ts"></script>
</head>
<body>
<my-element>
<p>This is child content</p>
</my-element>
</body>
</html>
Web 组件
打开 src/my-element.ts,并使用以下内容更新:
import { html, css, LitElement } from "lit";
import { customElement, property, state } from "lit/decorators.js";
@customElement("my-element")
export class MyElement extends LitElement {
static styles = css`
:host {
display: block;
border: solid 1px gray;
padding: 16px;
max-width: 800px;
}
`;
@property() name = "World";
@state() count = 0;
render() {
return html`
<h1>Hello, ${this.name}!</h1>
<button @click=${() => this.modify(1)} part="button">
Click Count: ${this.count}
</button>
<slot></slot>
`;
}
modify(val: number) {
this.count += val;
}
reset() {
this.count = 0;
}
async firstUpdated() {
window.addEventListener(
"message",
(e: any) => {
const message = e.data;
const { command } = message;
if (command === "reset") {
this.reset();
}
},
false
);
}
}
这里我们只是在示例的基础上进行修改,添加用于与 VSCode 扩展通信的消息监听器、用于更新计数的方法,以及更新渲染方法。
VSCode 通过 post 消息与插件通信,因为 UI 会在 iframe 中加载。
现在,我们来编写 src/extension.ts 中的扩展代码。首先,添加将在多处引用的顶层声明。
import * as vscode from "vscode";
const WEB_DIR: string = "build";
const WEB_SCRIPT: string = "main.js";
const TITLE: string = "Lit Example";
const TAG: string = "my-element";
const possible = [
"ABCDEFGHIJKLMNOPQRSTUVWXYZ",
"abcdefghijklmnopqrstuvwxyz",
"0123456789",
].join("");
function getNonce() {
let text = "";
for (let i = 0; i < 32; i++) {
const char = possible.charAt(Math.floor(Math.random() * possible.length));
text += char;
}
return text;
}
我们还创建了一个 getNonce 方法,用于确保加载的脚本正是我们传入的脚本。
现在创建一个 Panel,用于容纳插件的 UI:
class Panel {
public static currentPanel: Panel | undefined;
public static readonly viewType = "litExample";
private _disposables: vscode.Disposable[] = [];
public static createOrShow(extensionUri: vscode.Uri) {
const column = vscode.window.activeTextEditor
? vscode.window.activeTextEditor.viewColumn
: undefined;
if (Panel.currentPanel) {
Panel.currentPanel.panel.reveal(column);
return;
}
const panel = vscode.window.createWebviewPanel(
Panel.viewType,
TITLE,
column || vscode.ViewColumn.One,
getWebviewOptions(extensionUri)
);
Panel.currentPanel = new Panel(panel, extensionUri);
}
public static revive(panel: vscode.WebviewPanel, extensionUri: vscode.Uri) {
Panel.currentPanel = new Panel(panel, extensionUri);
}
private constructor(
public readonly panel: vscode.WebviewPanel,
public readonly extensionUri: vscode.Uri
) {
this._update();
this.panel.onDidDispose(() => this.dispose(), null, this._disposables);
this.panel.onDidChangeViewState(
(_) => {
if (this.panel.visible) {
this._update();
}
},
null,
this._disposables
);
this.panel.webview.onDidReceiveMessage(
(message) => {
switch (message.command) {
case "alert":
vscode.window.showErrorMessage(message.text);
return;
}
},
null,
this._disposables
);
}
public sendMessage(command: string) {
this.panel.webview.postMessage({ command: command });
}
public dispose() {
Panel.currentPanel = undefined;
this.panel.dispose();
while (this._disposables.length) {
const x = this._disposables.pop();
if (x) {
x.dispose();
}
}
}
private _update() {
const webview = this.panel.webview;
webview.html = this._getHtmlForWebview(webview);
}
private _getHtmlForWebview(webview: vscode.Webview) {
const scriptPathOnDisk = vscode.Uri.joinPath(
this.extensionUri,
WEB_DIR,
WEB_SCRIPT
);
const scriptUri = webview.asWebviewUri(scriptPathOnDisk);
const nonce = getNonce();
const slot = "<p>This is child content</p>";
return `<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>${TITLE}</title>
</head>
<body class="vscode-light">
<${TAG} nonce="${nonce}" >
${slot}
</${TAG}>
<script nonce="${nonce}" type="module" src="${scriptUri}"></script>
</body>
</html>`;
}
}
请注意,我们重新创建了 HTML,而没有使用
index.html。这样既可以将组件用于已部署的网站,也可以用于具有独立应用逻辑代码的扩展。
其余代码都是用于管理面板状态并在完成后释放资源的样板代码。
现在,我们可以添加用于加载插件并监听命令的方法:
export function activate(context: vscode.ExtensionContext) {
context.subscriptions.push(
vscode.commands.registerCommand("lit.start", () => {
Panel.createOrShow(context.extensionUri);
})
);
context.subscriptions.push(
vscode.commands.registerCommand("lit.reset", () => {
if (Panel.currentPanel) {
Panel.currentPanel.sendMessage("reset");
}
})
);
if (vscode.window.registerWebviewPanelSerializer) {
vscode.window.registerWebviewPanelSerializer(Panel.viewType, {
async deserializeWebviewPanel(
webviewPanel: vscode.WebviewPanel,
state: any
) {
console.log(`Received state: ${state}`);
webviewPanel.webview.options = getWebviewOptions(context.extensionUri);
Panel.revive(webviewPanel, context.extensionUri);
},
});
}
}
function getWebviewOptions(extensionUri: vscode.Uri): vscode.WebviewOptions {
return {
enableScripts: true,
localResourceRoots: [vscode.Uri.joinPath(extensionUri, WEB_DIR)],
};
}
这里我们加载扩展,并在执行 lit.reset 命令时传递消息。我们还返回 getWebviewOptions 选项,其中 enableScripts 设置为 true,以便运行注入的 js。
最终代码应如下所示:
import * as vscode from "vscode";
const WEB_DIR: string = "build";
const WEB_SCRIPT: string = "main.js";
const TITLE: string = "Lit Example";
const TAG: string = "my-element";
export function activate(context: vscode.ExtensionContext) {
context.subscriptions.push(
vscode.commands.registerCommand("lit.start", () => {
Panel.createOrShow(context.extensionUri);
})
);
context.subscriptions.push(
vscode.commands.registerCommand("lit.reset", () => {
if (Panel.currentPanel) {
Panel.currentPanel.sendMessage("reset");
}
})
);
if (vscode.window.registerWebviewPanelSerializer) {
vscode.window.registerWebviewPanelSerializer(Panel.viewType, {
async deserializeWebviewPanel(
webviewPanel: vscode.WebviewPanel,
state: any
) {
console.log(`Received state: ${state}`);
webviewPanel.webview.options = getWebviewOptions(context.extensionUri);
Panel.revive(webviewPanel, context.extensionUri);
},
});
}
}
function getWebviewOptions(extensionUri: vscode.Uri): vscode.WebviewOptions {
return {
enableScripts: true,
localResourceRoots: [vscode.Uri.joinPath(extensionUri, WEB_DIR)],
};
}
class Panel {
public static currentPanel: Panel | undefined;
public static readonly viewType = "litExample";
private _disposables: vscode.Disposable[] = [];
public static createOrShow(extensionUri: vscode.Uri) {
const column = vscode.window.activeTextEditor
? vscode.window.activeTextEditor.viewColumn
: undefined;
if (Panel.currentPanel) {
Panel.currentPanel.panel.reveal(column);
return;
}
const panel = vscode.window.createWebviewPanel(
Panel.viewType,
TITLE,
column || vscode.ViewColumn.One,
getWebviewOptions(extensionUri)
);
Panel.currentPanel = new Panel(panel, extensionUri);
}
public static revive(panel: vscode.WebviewPanel, extensionUri: vscode.Uri) {
Panel.currentPanel = new Panel(panel, extensionUri);
}
private constructor(
public readonly panel: vscode.WebviewPanel,
public readonly extensionUri: vscode.Uri
) {
this._update();
this.panel.onDidDispose(() => this.dispose(), null, this._disposables);
this.panel.onDidChangeViewState(
(_) => {
if (this.panel.visible) {
this._update();
}
},
null,
this._disposables
);
this.panel.webview.onDidReceiveMessage(
(message) => {
switch (message.command) {
case "alert":
vscode.window.showErrorMessage(message.text);
return;
}
},
null,
this._disposables
);
}
public sendMessage(command: string) {
this.panel.webview.postMessage({ command: command });
}
public dispose() {
Panel.currentPanel = undefined;
this.panel.dispose();
while (this._disposables.length) {
const x = this._disposables.pop();
if (x) {
x.dispose();
}
}
}
private _update() {
const webview = this.panel.webview;
webview.html = this._getHtmlForWebview(webview);
}
private _getHtmlForWebview(webview: vscode.Webview) {
const scriptPathOnDisk = vscode.Uri.joinPath(
this.extensionUri,
WEB_DIR,
WEB_SCRIPT
);
const scriptUri = webview.asWebviewUri(scriptPathOnDisk);
const nonce = getNonce();
const slot = "<p>This is child content</p>";
const htmlSource = `
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>${TITLE}</title>
</head>
<body class="vscode-light">
<${TAG} nonce="${nonce}" >
${slot}
</${TAG}>
<script nonce="${nonce}" type="module" src="${scriptUri}"></script>
</body>
</html>`;
return htmlSource;
}
}
const possible = [
"ABCDEFGHIJKLMNOPQRSTUVWXYZ",
"abcdefghijklmnopqrstuvwxyz",
"0123456789",
].join("");
function getNonce() {
let text = "";
for (let i = 0; i < 32; i++) {
const char = possible.charAt(Math.floor(Math.random() * possible.length));
text += char;
}
return text;
}
运行
请确保运行 npm i 安装依赖项。
运行 npm run compile 编译扩展。
按 F5 打开并调试扩展。
![]()
运行 lit: open plugin 或 lit: reset 命令来打开扩展:
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扩展打开后,在命令面板中运行 Developer: Open Webview Developer Tools 来调试扩展。
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