Why should not use if and for directives together on the same element?

It is recommended not to use v-if on the same element as v-for. Because v-if directive has a higher priority than v-for.

There are two cases where developers try to use this combination,

1. To filter items in a list

For example, if you try to filter the list using v-if tag,

<ul>
<li
v-for="user in users"
v-if="user.isActive"
:key="user.id"
>
{{ user.name }}
<li>
</ul>

This can be avoided by preparing the filtered list using computed property on the initial list

computed: {
activeUsers: function () {
return this.users.filter(function (user) {
return user.isActive
})
}
}
...... //
...... //
<ul>
<li
v-for="user in activeUsers"
:key="user.id">
{{ user.name }}
<li>
</ul>

2. To avoid rendering a list if it should be hidden

For example, if you try to conditionally check if the user is to be shown or hidden

<ul>
<li
v-for="user in users"
v-if="shouldShowUsers"
:key="user.id"
>
{{ user.name }}
<li>
</ul>

This can be solved by moving the condition to a parent by avoiding this check for each user

<ul v-if="shouldShowUsers">
<li
v-for="user in users"
:key="user.id"
>
{{ user.name }}
<li>
</ul>