Pass wire picklist value to connectedCallback

Question

I have a LWC where I am populating the picklist using wire service.

@wire(getPicklistValues , {recordTypeId: '$accountItem.data.defaultRecordTypeId',fieldApiName: ACCT_ITEM_STATUS })
acctStatus; 

Wire populates picklist

  <template if:true={acctStatus.data}>
        <lightning-layout-item size="3" padding="around-small">
            <lightning-combobox value={value} placeholder="Complete" onchange = {handleAcctChange} options={acctStatus.data.values} label="Account Item Status" ></lightning-combobox>
        </lightning-layout-item>
    </template>

2 Questions
1.How can I pass the the placeholder value to a connectedcallback?
2.How do I pass the picklist onchange value to the connectedcallback?

import getAcctLayout from '@salesforce/apex/AccountController.getAccountItems';

async connectedCallback() {

const acctLayout = await getAcctLayout({acctId: this.recordId, acctStatus: picklist value})

Answer 1

you have to use reactive wire mechanism using $, added sample code

import {LightningElement, wire} from 'lwc';
import getAcctLayout from '@salesforce/apex/AccountController.getAccountItems';


   selectedPLValue = '';
   async connectedCallback() {
      this.selectedPLValue  = 'Complete'; // call wire service first time loads after set the value complete
   }
   @wire(getAcctLayout({acctId: this.recordId, acctStatus: '$selectedPLValue'}))
   acctLayout;

   handleAcctChange(event) {
       this.selectedPLValue  = event.detail.value; // call wire service when value changes
   }