How to fetch Picklist values in Lightning Web Components(lwc)

This post explains how to fetch picklist values in Lightning web components(lwc)

use getPicklistValues wire adapter to fetch picklist values for a specified field.

Parameters:

recordTypeId—(Required) The ID of the record type. Use the Object Info defaultRecordTypeId property, which is returned from getObjectInfo or getRecordUi.
fieldApiName—(Required) The API name of the picklist field on a supported object.
propertyOrFunction—A private property or function that receives the stream of data from the wire service. If a property is decorated with @wire, the results are returned to the property’s data property or error property. If a function is decorated with  @wire, the results are returned in an object with a data property and an error property.

Demo:
PicklistValuesDemo.html

<template>
    <lightning-card title="Account PicklistValues">
        <template if:true={IndustryPicklistValues.data}>
            <lightning-combobox name="progress"
                                label="Industry"
                                value={value}
                                placeholder="-Select-"
                                options={IndustryPicklistValues.data.values}
                                onchange={handleChange} >
            </lightning-combobox>
      </template><br/>
      you selected industry: <b>{value}</b><br/><br/>
      <template if:true={IndustryPicklistValues.data}>
        Account Type: <br/>
        <template for:each={TypePicklistValues.data.values} for:item="item">
            <lightning-input
                placeholder="Account Type"
                key={item.value}
                label={item.label}
                data-value={item.value}
                type="checkbox"></lightning-input>
        </template>
    </template>
    </lightning-card>
</template>

PicklistValuesDemo.js

import { LightningElement, track, wire} from 'lwc';
import { getPicklistValues } from 'lightning/uiObjectInfoApi';
import { getObjectInfo } from 'lightning/uiObjectInfoApi';
import ACCOUNT_OBJECT from '@salesforce/schema/Account';
import INDUSTRY_FIELD from '@salesforce/schema/Account.Industry';
import Type_FIELD from '@salesforce/schema/Account.Type';

export default class PicklistValuesDemo extends LightningElement {
    @track value;

    @wire(getObjectInfo, { objectApiName: ACCOUNT_OBJECT })
    objectInfo;

    @wire(getPicklistValues, { recordTypeId: '$objectInfo.data.defaultRecordTypeId', fieldApiName: Type_FIELD})
    TypePicklistValues;

    @wire(getPicklistValues, { recordTypeId: '$objectInfo.data.defaultRecordTypeId', fieldApiName: INDUSTRY_FIELD})
    IndustryPicklistValues;

    handleChange(event) {
        this.value = event.detail.value;
    }
}

PicklistValuesDemo.js-meta.xml

<?xml version="1.0" encoding="UTF-8"?>
<LightningComponentBundle xmlns="http://soap.sforce.com/2006/04/metadata" fqn="picklistValuesDemo">
    <apiVersion>45.0</apiVersion>
    <isExposed>true</isExposed>
    <targets>
        <target>lightning__AppPage</target>
        <target>lightning__RecordPage</target>
        <target>lightning__HomePage</target>
    </targets>
</LightningComponentBundle>

Result

Resource
getPicklistvalues