vue-emit-helper

Helper functions for emitting values from Vue component using composition API.

• Installation
• Synopsis
• Details
• API
• vue-emit-helper
  • Functions
    • useEmitHelper
• Interfaces
• Interface: EmitHelper
  • Hierarchy
  • Properties
    • attrs
    • emitWith
    • getVModel
    • listeners

Installation

Synopsis

Please see full example on GitHub or CodeSandbox

<template>
  <div>
    <input v-model="unitPrice" />
    <input v-model="quantity" />
    <input ... v-on="listeners" />
    <input :value="value.modifications[default]" @input="emitWith(`modifications.${default}`, $event)" />
  </div>
</template>
 
<script lang="ts">
import useEmitHelper from "vue-emit-helper";
 
export default defineComponent({
  props: {
    value: { type: Object, required: true } // i.e object value: { quantity: 4, unitPrice: 12.3, modifications: {...} }
  },
  setup(props, context) {
    // Default options are: { prop: "value", event: "input" }
    const { getVModel, emitWith, listeners, attrs } = useEmitHelper(props, context);
 
    // ... your setup code
 
    return {
      quantity: getVModel("quantity"),
      unitPrice: getVModel("unitPrice"),
      default: "vat", // For advanced usage shown in example template.
    }
  }
})
</script>

Details

Using Vue composition API, provides helper functions which emits (immutable) values with deep objects/arrays/Maps. Also provides functions which returns values used as v-model, which emits configured event automatically.

For example:

const { getVModel } = useEmitHelper(props, context);
 
const quantity = getVModel("item.quantity");
 
// Approximately equal to:
const quantity_2 = computed({
  get: () => props.value.item.quantity,
  set: (newQuantity) => context.emit("input", immutableSet("props.value", "item.quantity", newQuantity))
})

API

vue-emit-helper

vue-emit-helper

Functions

useEmitHelper

▸ useEmitHelper<P, PK>(props: P, context: SetupContext, __namedParameters: object): EmitHelper

Defined in index.ts:75

Creates helper functions for emitting values from Vue component.

Example

<template>
  <div>
    <v-numeric v-model="unitPrice" />
    <v-numeric v-model="quantity" />
    <v-numeric ... v-on="listeners" />
    <v-amount :value="value.modifications[default]" @input="emitWith(`modifications.${default}`, $event)" />
  </div>
</template>
 
<script lang="ts">
import useEmitHelper from "vue-emit-helper";
 
export default defineComponent({
  props: {
    value: { type: Object, required: true } // Example: { quantity: 4, unitPrice: 12.3, modifications: {...} }
  },
  setup(props, context) {
    const { getVModel, emitWith, listeners } = useEmitHelper(props, context, { prop: "value", event: "input" });
    // ... your setup code
 
    // See example in `getVModel` also.
    return {
      quantity: getVModel("quantity"),
      unitPrice: getVModel("unitPrice"),
      default: "vat"
    }
  }
})
</script>

Type parameters:

▪ P: Record‹string, any›

▪ PK: keyof P

Parameters:

▪ props: P

is props of Vue component passed to setup() function.

▪ context: SetupContext

is setup context of Vue component passed to setup() function.

▪Default value __namedParameters: object= {}

Name	Type	Default
event	string	"input"
prop	PK	"value" as PK

Returns: EmitHelper

helper functions.

Interfaces

vue-emit-helper › EmitHelper

Interface: EmitHelper

Hierarchy

• EmitHelper

Properties

attrs

• attrs: Ref‹Record‹string, string››

Defined in index.ts:34

Computed value of object of attrs except value of emitted event. This is used to prevent down passing of emiited value.

---

emitWith

• emitWith: function

Defined in index.ts:12

Emits props.value after immutably setting given attribute to given value. If new value passed is undefined, it deletes related key instead of setting it to undefined.

param is the attribute name or path in props.value.

param is the new value to be set, or undefined to delete related key from props.value.

Type declaration:

▸ (attribute: Path, value?: any): void

Parameters:

Name	Type
attribute	Path
value?	any

---

getVModel

• getVModel: function

Defined in index.ts:30

Returns vue computed value to be used target of a v-model which emits immutable value with new value of the given attribute. If new value passed to v-model is undefined, it deletes related key instead of setting it to undefined.

Example

const { getVModel } = useEmitHelper(props, context, { prop: "value", event: "input" });
const quantity = getVModel("item.quantity");
 
// getVModel("item.quantity") is approximately equal to:
const quantity = computed({
  get: () => props.value.item.quantity,
  set: (newQuantity) => context.emit("input", immutableSet("props.value", "item.quantity", newQuantity))
})

param is the attribute name or path in props.value.

returns computed value.

Type declaration:

▸ (attribute?: Path): Ref‹any›

Parameters:

Name	Type
attribute?	Path

---

listeners

• listeners: Ref‹Record‹string, Function››

Defined in index.ts:32

Computed value of object of events except emitted event. This is used to prevent down passing of emiited event.