How do you communicate from child to parent using events?
Interviewer Expectations for this Question
01
Core Competency
Assesses fundamental understanding of Vue.js conventions, runtime behavior, and memory/performance considerations.
02
Evaluation Criteria
Hiring managers look for precision, avoidance of ambiguous jargon, and ability to explain trade-offs under real production conditions.
Comprehensive Model Answer
Verified Solution
If you want child wants to communicate back up to the parent, then emit an event from child using $emit object to
parent,
Vue.component('todo-item', {
props: ['todo'],
template: `
<div class="todo-item">
<h3>{{ todo.title }}</h3>
<button v-on:click="$emit('increment-count', 1)">
Add
</button>
<div v-html="todo.description"></div>
</div>
`
})
Now you can use this todo-item in parent component to access the count value.
<ul v-for="todo in todos">
<li>
<todo-item
v-bind:key="todo.id"
v-bind:todo="todo"
v-on:increment-count="total += 1"
/></todo-item>
</li>
</ul>
<span> Total todos count is {{total}}</span>
****
Candidate Response Strategy & Interview Tips
- Start with a concise one-sentence summary: Deliver a direct, confident answer first before expanding into nuances.
- Demonstrate real-world trade-offs: Discuss where this approach excels and when you would avoid it in production systems.
- Discuss complexity & edge cases: Proactively explain time/space complexity or boundary conditions (null values, scale limits).
- Prepare for interviewer follow-ups: Technical hiring panels frequently probe deeper into concurrency, backward compatibility, or alternative libraries.