# Getting and Setting
# v-model
The most common use case for vue-select is to have the chosen value synced with a parent component.
vue-select takes advantage of the v-model
syntax to sync values with a parent. The v-model
syntax works with primitives and objects.
<v-select v-model="selected" />
Note that when using the multiple
prop, the v-model
value will always be an array.
# Props and Events
Sometimes v-model
might not fit your use case. For example, when working
with Vuex, you'll need to trigger a mutation rather than mutating a value
directly. In that case, maybe you need to bind a pre-selected value, and trigger a mutation when it
changes.
vue-select exposes the value
prop and an input
event to enable this. This combo of props and
events is also how Vue wires up the v-model
syntax internally.
# Prop: value
The value
prop lets vue-select know what value is currently selected. It will accept strings,
numbers or objects. If you're using a multiple
v-select, you'll want to pass an array.
<v-select :value="selected" />
🤓 Anytime you bind the `value` prop directly, you're responsible for updating the bound
variable in your code using the @input
event.
# Event: input
The input
event is triggered anytime the value state changes, and is emitted with the value
state as it's only parameter.
# Vuex Support
The value
prop and emit
event are very useful when using a state management tool, like Vuex. You
can bind the selected value with :value="$store.myValue"
, and use the input
event to trigger a
mutation, or dispatch an action – or anything else you might need to do when the selection changes.
<v-select :value="$store.myValue" @input="setSelected" />
methods: {
setSelected(value)
{
// trigger a mutation, or dispatch an action
}
}
# Single/Multiple
By default, vue-select supports choosing a single value. If you need multiple values, use the
multiple
boolean prop, much the same way you would on an HTML <select>
element. When multiple
is true, v-model
and value
must be an array.
<v-select multiple v-model="selected" :options="['Canada','United States']" />
# Transforming Selections
When the options
array contains objects, vue-select returns the whole object as dropdown value
upon selection. This approach makes no assumptions about the data you need, and provides a lot of
flexibility. However, there will be situations where you just need to return a single key from an
object.
# Returning a single key with reduce
If you need to return a single key, or transform the selection before it is synced, vue-select
provides a reduce
callback that allows you to transform a selected option before it is passed to
the @input
event. Consider this data structure:
let options = [{code: 'CA', country: 'Canada'}];
If we want to display the country
, but return the code
to v-model
, we can use the reduce
prop to receive only the data that's required.
<v-select :options="options" :reduce="country => country.code" label="country" />
# Deep Nested Values
The reduce
property also works well when you have a deeply nested value:
{
country: 'canada',
meta: {
code: 'ca'
provinces: [...],
}
}
<v-select :options="options" :reduce="country => country.meta.code" label="country" />
v-model value: null
# Caveats with reduce
The most common issue with reduce
is when the component displays your reduced value instead of
it's label. This happens when you supply Vue Select a value
or v-model
binding with a reduced_
value, but the complete option object is not present in the options
array.
<template>
<v-select
v-model="selected"
:reduce="(option) => option.id"
:options="[
{ label: 'One', id: 1 },
{ label: 'Two', id: 2 },
]"
/>
</template>
<script>
export default {
data() {
return {
selected: 3,
}
},
}
</script>
In the example above, the component was supplied with an ID that doesn't exist in the options
array. When value
changes, Vue Select searches the supplied options, running each one
through reduce
until the corresponding option is found. When that option doesn't exist, Vue Select
will end up displaying the value
supplied.
WARNING
When providing Vue Select with a reduced value
- the object that the value was reduced from must
exist in the options
array.
# Tagging
To allow input that's not present within the options, set the taggable
prop to true.
<v-select taggable multiple />
If you want added tags to be pushed to the options array, set push-tags
to true.
<v-select taggable multiple push-tags />
# Using taggable
& reduce
together
When combining taggable
with reduce
, you must define the createOption
prop. The
createOption
function is responsible for defining the structure of the objects that Vue Select
will create for you when adding a tag. It should return a value that has the same properties as the
rest of your options
.
If you don't define createOption
, Vue Select will construct a simple object following this
structure:
{[this.label]: searchText}
. If you're using reduce
, this is probably not what your options look
like, which is why you'll need to set the function yourself.
Example
We have a taggable select for adding books to a collection. We're just concerned about getting the book title added, and our server side code will add the author details in a background process. The user has already selected a book.
const options = [
{
title: "HTML5",
author: {
firstName: "Remy",
lastName: "Sharp"
}
}
];
<v-select
taggable
multiple
label="title"
:options="options"
:create-option="book => ({ title: book, author: { firstName: '', lastName: '' } })"
:reduce="book => `${book.author.firstName} ${book.author.lastName}`"
/>