Babel plugin for Vue 2.0 JSX
- If using Babel 7, use 4.x
- If using Babel 6, use 3.x
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Assumes you are using Babel with a module bundler e.g. Webpack, because the spread merge helper is imported as a module to avoid duplication.
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This is mutually exclusive with
babel-plugin-transform-react-jsx.
npm install\ babel-plugin-syntax-jsx\ babel-plugin-transform-vue-jsx\ babel-helper-vue-jsx-merge-props\ babel-preset-env\ --save-devIn your .babelrc:
{ "presets": ["env"], "plugins": ["transform-vue-jsx"] }The plugin transpiles the following JSX:
<div id="foo">{this.text}</div>To the following JavaScript:
h('div', { attrs: { id: 'foo' } }, [this.text])Note the h function, which is a shorthand for a Vue instance's $createElement method, must be in the scope where the JSX is. Since this method is passed to component render functions as the first argument, in most cases you'd do this:
Vue.component('jsx-example', { render (h) { // <-- h must be in scope return <div id="foo">bar</div> } })Starting with version 3.4.0 we automatically inject const h = this.$createElement in any method and getter (not functions or arrow functions) declared in ES2015 syntax that has JSX so you can drop the (h) parameter.
Vue.component('jsx-example', { render () { // h will be injected return <div id="foo">bar</div> }, myMethod: function () { // h will not be injected return <div id="foo">bar</div> }, someOtherMethod: () => { // h will not be injected return <div id="foo">bar</div> } }) @Component class App extends Vue { get computed () { // h will be injected return <div id="foo">bar</div> } }First, Vue 2.0's vnode format is different from React's. The second argument to the createElement call is a "data object" that accepts nested objects. Each nested object will be then processed by corresponding modules:
render (h) { return h('div', { // Component props props: { msg: 'hi', onCustomEvent: this.customEventHandler }, // normal HTML attributes attrs: { id: 'foo' }, // DOM props domProps: { innerHTML: 'bar' }, // Event handlers are nested under "on", though // modifiers such as in v-on:keyup.enter are not // supported. You'll have to manually check the // keyCode in the handler instead. on: { click: this.clickHandler }, // For components only. Allows you to listen to // native events, rather than events emitted from // the component using vm.$emit. nativeOn: { click: this.nativeClickHandler }, // class is a special module, same API as `v-bind:class` class: { foo: true, bar: false }, // style is also same as `v-bind:style` style: { color: 'red', fontSize: '14px' }, // other special top-level properties key: 'key', ref: 'ref', // assign the `ref` is used on elements/components with v-for refInFor: true, slot: 'slot' }) }The equivalent of the above in Vue 2.0 JSX is:
render (h) { return ( <div // normal attributes or prefix with on props. id="foo" propsOnCustomEvent={this.customEventHandler} // DOM properties are prefixed with `domProps` domPropsInnerHTML="bar" // event listeners are prefixed with `on` or `nativeOn` onClick={this.clickHandler} nativeOnClick={this.nativeClickHandler} // other special top-level properties class={{ foo: true, bar: false }} style={{ color: 'red', fontSize: '14px' }} key="key" ref="ref" // assign the `ref` is used on elements/components with v-for refInFor slot="slot"> </div> ) }If a custom element starts with lowercase, it will be treated as a string id and used to lookup a registered component. If it starts with uppercase, it will be treated as an identifier, which allows you to do:
import Todo from './Todo.js' export default { render (h) { return <Todo/> // no need to register Todo via components option } }JSX spread is supported, and this plugin will intelligently merge nested data properties. For example:
const data = { class: ['b', 'c'] } const vnode = <div class="a" {...data}/>The merged data will be:
{ class: ['a', 'b', 'c'] }Note that almost all built-in Vue directives are not supported when using JSX, the sole exception being v-show, which can be used with the v-show={value} syntax. In most cases there are obvious programmatic equivalents, for example v-if is just a ternary expression, and v-for is just an array.map() expression, etc.
For custom directives, you can use the v-name={value} syntax. However, note that directive arguments and modifiers are not supported using this syntax. There are two workarounds:
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Pass everything as an object via
value, e.g.v-name={{ value, modifier: true }} -
Use the raw vnode directive data format:
const directives = [ { name: 'my-dir', value: 123, modifiers: { abc: true } } ] return <div {...{ directives }}/>