[SalesForce] Case Custom Button Lightning to Update Status

I am trying to update case status field on lightning detail page. We are not using case feed. I think lightning components cannot be added on case and Work Order detail page.
FYI: Actions on Case object in Lightning

What is the best approach. when i try to add lightning button it shows on the case feed.But i need on detail page.
Only approach i can think of is
New Button or Link :URL or Visualforce Page Button
I tried both. On click of the button,
I need to update the status to "Completed".
User should not refresh to reflect the change. Right now with this approach i need to refresh the page few times to reflect the changes.

Can someone please help.Also please let me know if there is any other approach.
URL: /apex/UpdateCasePage?cid={!Case.Id}

<apex:page controller="CaseUpdStatus" action="{!updateCasestatus}">
    <apex:form >
        <apex:pageMessages ></apex:pageMessages>
    </apex:form> 
    <script type="text/javascript">
        function RefreshPrimaryTab() 
        {
                    window.close();
                  window.top.location.href = '/{!cid}' ;
        }
    </script>    
</apex:page>

Class:

public with sharing class CaseUpdStatus{
    public string cId {get;set;}
    // constructor
    public CaseUpdStatus(){
        cId = apexpages.currentpage().getparameters().get('cid');
    }
    public pagereference updateCasestatus(){        
        // getting case Record Details
        List<case> lstCase = [SELECT ID,
                                        RecordType.Name,
                                        status
                                    FROM case
                                    WHERE ID =:cId];
        system.debug('\n--lstCase--'+lstCase);
        if(!lstCase.isEmpty()){                           
                lstCase[0].status= 'Completed';
                update lstCase;
                pagereference page = new Pagereference('/'+cId);
                page.setRedirect(true);
                return page;                                      
        }
        return null;             
    }
}