I'm new to VF and apex. Trying to create a custom clone functionality.

Question

Unable to pass contact from VF to the controller. I have to check if the contact is inactive on VF page if it inactive, allow user to change the contact and pass the changes to the controller. If contact is active, use the same. Here's what my VF page looks like:

    <apex:page standardController="Case" tabStyle="Case" lightningstylesheets="true"
 extensions="TestCase_Controller">
 <apex:sectionHeader title="{!$Label.ClaimAP_Clone_Title}" subtitle="{!Case.CaseNumber}"/>
<apex:form >
    <apex:pageBlock mode="inlineEdit" title="">
        <apex:pageblockButtons >
            <apex:commandButton action="{!cloneCase}" value="{!$Label.ClaimAP_Clone_ButtonClone}" />
            <apex:commandButton action="{!Cancel}" value="{!$Label.ClaimAP_Clone_ButtonCancel}" />
        </apex:pageblockButtons>
        <apex:pageBlockSection columns="1" title="{!$Label.ClaimAP_Clone_CloneLegend}" collapsible="false">
            <apex:inputField value="{!Case.ContactId}"/>
        </apex:pageBlockSection> 
    </apex:pageBlock>
</apex:form>
 <apex:pageMessages />

My controller is this:

    public class TestCase_Controller {
private ApexPages.StandardController controller {get; set;}
private Case CaseRecordQueried{get;set;}
public Case CaseRecord {get;set;}
public Case Contactid;

public TestCase_Controller(ApexPages.StandardController controller) {

    this.controller = controller;
    CaseRecord = (Case)controller.getRecord();
    Contactid = (Case)controller.getRecord();
    //Contactid = (Case)
    CaseRecordQueried = [select Id,
                            AccountId,
                            CaseNumber,
                            External_Reference_Number__c,
                            FSR__c,
                            Total_Lines__c,
                            Opportunity__c,
                            EU_Sample_Type__c,
                            Comments_For_Customer__c,
                            Shipment_Status__c,
                            Comments_for_Stratos__c,
                            Customer_PO__c,
                            Comments_for_Manager__c,
                            Division__c,
                            Lead__c,
                            Shipment__c,
                            Customer_Language__c,
                            Shipment_Contact__c,
                            Shipment_Contact_Phone__c,
                            Shipment_Address__c,
                            Work_in_progress__c,
                            Carrier__c,
                            UPS_Tracking_Nbr__c,
                            AWB_Number__c,
                            Country__c,
                            Comments_from_Stratos__c,
                            Cost_of_Sample__c,
                            Shipment_Cost__c,
                            Total_Cost__c,
                            Origin,
                            Description,
                            Priority,
                            Requires_Approval__c,
                            RecordTypeId
                     from Case
                     where id =: CaseRecord.Id];
}

public PageReference cloneCase() {

     String contactid = Contactid.ContactId;
     Savepoint sp = Database.setSavepoint();
     Case CaseCloned;
     try {
         CaseCloned = CaseRecordQueried.clone(false);
         insert CaseCloned;
     } catch (Exception e){
        Database.rollback(sp);
        ApexPages.addMessages(e);
        return null;
     }
    return new PageReference('/'+CaseCloned.id);

}

}

Answer 1

Above code should be like:

<apex:page standardController="Case" tabStyle="Case" lightningstylesheets="true"
extensions="TestCase_Controller">
<apex:sectionHeader title="{!$Label.ClaimAP_Clone_Title}" subtitle=" 
{!CaseRecordQueried.CaseNumber}"/>
<apex:form >
    <apex:pageBlock mode="inlineEdit" title="">
       <apex:pageblockButtons >
          <apex:commandButton action="{!cloneCase}" value="{!$Label.ClaimAP_Clone_ButtonClone}" />
          <apex:commandButton action="{!Cancel}" value="{!$Label.ClaimAP_Clone_ButtonCancel}" />
        </apex:pageblockButtons>
        <apex:pageBlockSection columns="1" title="{!$Label.ClaimAP_Clone_CloneLegend}" collapsible="false">
            <apex:inputField value="{!CaseRecordQueried.ContactId}"/>
        </apex:pageBlockSection> 
       </apex:pageBlock>
    </apex:form>
  <apex:pageMessages />
</apex:page>

Controller code should be like:

  public class TestCase_Controller {
     private ApexPages.StandardController controller {get; set;}
     public Case CaseRecordQueried{get;set;}

     public TestCase_Controller(ApexPages.StandardController controller) {
         this.controller = controller;
         CaseRecordQueried = [select Id,
                        AccountId,
                        ContactId,
                        CaseNumber,
                        External_Reference_Number__c,
                        FSR__c,
                        Total_Lines__c,
                        Opportunity__c,
                        EU_Sample_Type__c,
                        Comments_For_Customer__c,
                        Shipment_Status__c,
                        Comments_for_Stratos__c,
                        Customer_PO__c,
                        Comments_for_Manager__c,
                        Division__c,
                        Lead__c,
                        Shipment__c,
                        Customer_Language__c,
                        Shipment_Contact__c,
                        Shipment_Contact_Phone__c,
                        Shipment_Address__c,
                        Work_in_progress__c,
                        Carrier__c,
                        UPS_Tracking_Nbr__c,
                        AWB_Number__c,
                        Country__c,
                        Comments_from_Stratos__c,
                        Cost_of_Sample__c,
                        Shipment_Cost__c,
                        Total_Cost__c,
                        Origin,
                        Description,
                        Priority,
                        Requires_Approval__c,
                        RecordTypeId
                 from Case
                 where id =: controller.getId()];
       }

      public PageReference cloneCase() {
         String contactid = CaseRecordQueried.ContactId;
         Savepoint sp = Database.setSavepoint();
         Case CaseCloned;
        try {
           CaseCloned = CaseRecordQueried.clone(false);
           insert CaseCloned;
           } catch (Exception e){
         Database.rollback(sp);
         ApexPages.addMessages(e);
         return null;
       }
       return new PageReference('/'+CaseCloned.id);
    }
  }