How to override standard new button in Salesforce Lightning?

 Lightning:actionOverride interface enables a component to be used as an override for a standard action. We can override the View, New, Edit, and Tab standard actions on most standard and all custom components. The component needs to implement the interface Lightning:actionOverride
after which the component appears in the Lightning Component Bundle menu of an object action override properties panel.

Sample example:

<aura:component implements="lightning:actionOverride">

</aura:component>

Scenario:  Override the standard new button action on the contact object.

Solution:

1) Component: (Name=Contactinformation)

<aura:component controller="ContactInsertClass" implements="force:hasRecordId,flexipage:availableForAllPageTypes,lightning:actionOverride">

    <aura:attribute name="firstName" type="string"/>

    <aura:attribute name="lastName" type="string"/>

    <lightning:input label="Enter First Name" value="{!v.firstName}"/>

    <lightning:input label="Enter Last Name" value="{!v.lastName}"/>

    <lightning:button label="Add contact" onclick="{!c.addContact}"/>

</aura:component>

2) Javascript controller:

({

 addContact : function(component, event, helper) {

        alert('1111');

  var fName=component.get("v.firstName");

        var lName=component.get("v.lastName");

        var action=component.get('c.insertContact');

        action.setParams({

         

            parentAccountId:component.get("v.recordId"),

            firstName1:component.get("v.firstName"),

            lastName1:component.get("v.lastName")

           

        });

        action.setCallback(this,function(response){

            var state=response.getState();

            if(state==="SUCCESS")

            {

                alert('Contact inserted successfully');               

            }

           

        });

        $A.enqueueAction(action);

       

 }

})

3) Apex controller:

public class ContactInsertClass {

@AuraEnabled

public static contact insertContact(string parentAccountId,string firstName1,string lastName1)

{

    system.debug('Test');

    contact con=new contact();

    con.firstName=firstName1;

    con.lastName=lastName1;

    con.accountid=parentAccountId;

    insert con;

    return con;

   

}

}

Now, to override the standard new button action Go to >SETUP > OBJECT MANAGER > Buttons, Links, and Actions > Goto New > Click Edit.

Override the Lightning experience and Mobile view with the Lightning component.