How to make router param changes as reactive?
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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
When you navigate from one URL to other(mapped with a single component) using routes with params then the same
component instance will be reused. Even though it is more efficient than destroying the old instance and then
creating a new one, the lifecycle hooks of the component will not be called.
This problem can be solved using either of the below approaches,
- Watch the $route object:
const User = {
template: '<div>User {{ $route.params.name }} </div>',
watch: {
'$route' (to, from) {
// react to route changes...
}
}
}
- Use beforeRouteUpdate navigation guard: This is only available since 2.2 version.
const User = {
template: '<div>User {{ $route.params.name }} </div>',
beforeRouteUpdate (to, from, next) {
// react to route changes and then call next()
}
}
Note that the beforeRouteEnter guard does NOT have access to this. Instead you can pass a callback to next to
access the vm instance.
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