Use the {{did-insert}}, {{did-update}}, {{will-destroy}} modifiers from @ember/render-modifiers as template helpers.
The original idea came from this Pre-RFC.
ember install ember-render-helpers
Use Glint or <template> tag? ✨
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Update your template registry to extend this addon's. Check the Glint documentation for more information.
import '@glint/environment-ember-loose'; import type EmberRenderHelpersRegistry from 'ember-render-helpers/template-registry'; declare module '@glint/environment-ember-loose/registry' { export default interface Registry extends EmberRenderHelpersRegistry, /* other addon registries */ { // local entries } }
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In a
<template>tag, use the named import to consume the helpers.import { action } from '@ember/object'; import Component from '@glimmer/component'; import { didInsertHelper } from 'ember-render-helpers'; export default class HelloComponent extends Component { @action sayHello() { console.log('Hello!'); } <template> {{didInsertHelper this.sayHello}} </template> }
ember-render-helpers provides 3 helpers. To avoid name conflicts with @ember/render-modifiers, these helpers are suffixed with -helper.
{{did-insert-helper}}{{did-update-helper}}{{will-destroy-helper}}
All helpers expect a callback function as the 1st positional argument. You can pass parameters to this callback function as subsequent positional arguments, as named arguments, or using both.
import Component from '@glimmer/component';
import type { NamedParameters, PositionalParameters } from 'ember-render-helpers';
export default class HelloComponent extends Component {
@action sayHello(positional: PositionalParameters, _named: NamedParameters) {
const name = positional[0] as string;
console.log(`Hello, ${name}!`);
}
}Clicking the Toggle button will toggle the isVisible flag. When it switches
to true, onDidInsert will be called, because the {{did-insert-helper}} helper is
inserted. When it switches to false, onWillDestroy will be called, because
the {{will-destroy-helper}} helper is removed.
Clicking the Random button will set randomValue to a new random value. Every
time this happens, while isVisible is true, onDidUpdate will be called,
because one of the parameters passed to the {{did-update-helper}} helper was updated.
Clicking the Random button does not cause {{did-insert-helper}} or
{{will-destroy-helper}} to call onDidInsert and onWillDestroy, since these
helpers are not triggered by parameter updates.
import { action } from '@ember/object';
import Component from '@glimmer/component';
import { tracked } from '@glimmer/tracking';
export default class extends Component {
@tracked isVisible = false;
@tracked randomValue?: number;
@action
toggleVisibility() {
this.isVisible = !this.isVisible;
}
@action
rollTheDice() {
this.randomValue = Math.random();
}
@action
onDidInsert(positional: unknown[], named: Record<string, unknown>) {
console.log({ positional, named });
// => { positional: [1, 2, 3, 0.1337...], named: { foo: 'bar', qux: 'baz' } }
}
@action
onWillDestroy(positional: unknown[], named: Record<string, unknown>) {
console.log({ positional, named });
// => { positional: [1, 2, 3, 0.1337...], named: { foo: 'bar', qux: 'baz' } }
}
@action
onDidUpdate(positional: unknown[], named: Record<string, unknown>) {
console.log({ positional, named });
// => { positional: [1, 2, 3, 0.1337...], named: { foo: 'bar', qux: 'baz' } }
}
}