How do you access the root instance?
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
The root instance(new Vue()) can be accessed with the $root property.
Let's see the usage of root instance with an example.
First let's create a root instance with properties and methods as below,
// The root Vue instance
new Vue({
data: {
age: 26
},
computed: {
fullName: function () { /* ... */ }
},
methods: {
interest: function () { /* ... */ }
}
})
Now you can access root instance data and it's methods with in subcomponents as below,
// Get root data
this.$root.age
// Set root data
this.$root.age = 29
// Access root computed properties
this.$root.fullName
// Call root methods
this.$root.interest()
It is recommend using Vuex to manage state instead of using root instance as a global store.
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