Enable two-way data binding for form fields saved in a Vuex store
npm install vuex-map-fields
> Enable two-way data binding for form fields saved in a Vuex store.
``bash`
npm install --save vuex-map-fields
The following example component shows the most basic usage, for mapping fields to the Vuex store using two-way data binding with v-model, without directly modifying the store itself, but using getter and setter functions internally (as it is described in the official Vuex documentation: Two-way Computed Property).
#### Store
`js
import Vue from 'vue';
import Vuex from 'vuex';
// Import the getField getter and the updateField
// mutation function from the module.
import { getField, updateField } from 'vuex-map-fields';
Vue.use(Vuex);
export default new Vuex.Store({
state: {
fieldA: '',
fieldB: '',
},
getters: {
// Add the getField getter to thegetters
// of your Vuex store instance.updateField
getField,
},
mutations: {
// Add the mutation to themutations
// of your Vuex store instance.`
updateField,
},
});
#### Component
`html
`
Oftentimes you want to have nested properties in the Vuex store. vuex-map-fields supports nested data structures by utilizing the object dot string notation.
#### Store
`js
import Vue from 'vue';
import Vuex from 'vuex';
import { getField, updateField } from 'vuex-map-fields';
Vue.use(Vuex);
export default new Vuex.Store({
state: {
user: {
firstName: '',
lastName: '',
},
addresses: [
{
town: '',
},
],
},
getters: {
getField,
},
mutations: {
updateField,
},
});
`
#### Component
`html
`
Sometimes you might want to give your computed properties different names than what you're using in the Vuex store. Renaming properties is made possible by passing an object of fields to the mapFields function instead of an array.
`html
`
By default vuex-map-fields is searching for the given properties starting from the root of your state object. Depending on the size of your application, the state object might become quite big and therefore updating the state starting from the root might become a performance issue. To circumvent such problems, it is possible to create a custom mapFields() function which is configured to access custom mutation and getter functions which don't start from the root of the state object but are accessing a specific point of the state.
#### Store
`js
import Vue from 'vue';
import Vuex from 'vuex';
import { getField, updateField } from 'vuex-map-fields';
Vue.use(Vuex);
export default new Vuex.Store({
state: {
user: {
firstName: '',
lastName: '',
},
},
getters: {
// By wrapping the getField() function we're`
// able to provide a specific property of the state.
getUserField(state) {
return getField(state.user);
},
},
mutations: {
// Mutating only a specific property of the state
// can be significantly faster than mutating the
// whole state every time a field is updated.
updateUserField(state, field) {
updateField(state.user, field);
},
},
});
#### Component
`html
`
Vuex makes it possible to divide the store into modules.
#### Store
`js
import Vue from 'vue';
import Vuex from 'vuex';
import { createHelpers } from 'vuex-map-fields';
// Because by default, getters and mutations in Vuex
// modules, are globally accessible and not namespaced,
// you most likely want to rename the getter and mutation
// helpers because otherwise you can't reuse them in multiple,
// non namespaced modules.
const { getFooField, updateFooField } = createHelpers({
getterType: 'getFooField',
mutationType: 'updateFooField',
});
Vue.use(Vuex);
export default new Vuex.Store({
// ...
modules: {
fooModule: {
state: {
foo: '',
},
getters: {
getFooField,
},
mutations: {
updateFooField,
},
},
},
});
`
#### Component
`html
`
By default, mutations and getters inside modules are registered under the global namespace – but you can mark modules as namespaced which prevents naming clashes of mutations and getters between modules.
#### Store
`js
import Vue from 'vue';
import Vuex from 'vuex';
import { getField, updateField } from 'vuex-map-fields';
Vue.use(Vuex);
export default new Vuex.Store({
// ...
modules: {
fooModule: {
namespaced: true,
state: {
foo: '',
},
getters: {
getField,
},
mutations: {
updateField,
},
},
},
});
`
#### Component
`html
`
Or you can pass the module namespace string as the first argument of the mapFields() function.
`html
`
If you want to build a form which allows the user to enter multiple rows of a specific data type with multiple fields (e.g. multiple addresses) you can use the multi-row field mapping function.
#### Store
`js
import Vue from 'vue';
import Vuex from 'vuex';
import { getField, updateField } from 'vuex-map-fields';
Vue.use(Vuex);
export default new Vuex.Store({
// ...
state: {
addresses: [
{
zip: '12345',
town: 'Foo Town',
},
{
zip: '54321',
town: 'Bar Town',
},
],
},
getters: {
getField,
},
mutations: {
updateField,
},
});
`
#### Component
`html
`
Instead of accessing the state directly, since the 1.0.0 release, in order to enable the ability to implement custom getters and mutations, vuex-map-fields is using a getter function to access the state. This makes it necessary to add a getter function to your Vuex store.
`js
import Vue from 'vue';
import Vuex from 'vuex';
// You now have to also import the getField() function.
import { getField, updateField } from 'vuex-map-fields';
Vue.use(Vuex);
export default new Vuex.Store({
state: {
fieldA: '',
fieldB: '',
},
getters: {
// Add the getField getter to thegetters
// of your Vuex store instance.``
getField,
},
mutations: {
updateField,
},
});
Become a sponsor and get your logo in this README with a link to your site.
- Form Fields, Two-Way Data Binding and Vuex
- How to Handle Multi-row Forms with Vue, Vuex and vuex-map-fields
- How to Structure a Complex Vuex Store
Markus Oberlehner
Website: https://markus.oberlehner.net
Twitter: https://twitter.com/MaOberlehner
PayPal.me: https://paypal.me/maoberlehner
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MIT