Wrapper class Referencing?

Question

How do I reference my wrapper class in my prepareshipment method? My goal was to set tNumber and location to = my fields on my shipment object.

In my VF page I want tNumber and Location to display Tracking_Number__c and Location__c during the edit field. I had set location and tnumber like this prior and it worked fine in my vf page but I have more variables i need to set as well and that method would take forever:

    public string location{
    get {
        if( location == null ) location = ship.Location__c;
        return location;
        }
    set; 

Current class I Have with wrapper:

   public  with sharing class shipmentController {

    public shipment__c ship {get;set;}
    public String shipId {get;set;}

    public class shipWrapper{
        public String tNumber {get;set;}
        public String location {get;set;}

    public shipWrapper(Shipment__c ship){
        this.tNumber = ship.Tracking_Number__c;
        this.location = ship.location__c;
    }

}
public shipmentController() {
        shipId = ApexPages.currentPage().getParameters().get('shipId');
        if (shipid == null) {
            ship = new Shipment__c();
        return;
    }

    ship = [select id, location__c, tracking_number__c
                    from shipment__c
                    where id = :shipid];
    }
    public PageReference prepareShipment(ShipWrapper ShipWrapper) {
        ship.tracking_Number__c = shipWrapper.tnumber;
        ship.Location__c = shipWrapper.location;
        update ship;  

Edited code:

 public  with sharing class shipmentController {

public shipment__c ship {get;set;}
public String shipId {get;set;}
public shipWrapper wrapper { get; set;}

public class shipWrapper{
    public String tNumber {get;set;}
    public String location {get;set;}

public shipWrapper(Shipment__c ship){
    this.tNumber = ship.Tracking_Number__c;
    this.location = ship.location__c;
      }

  }
    public shipmentController() {
     wrapper = new shipmentWrapper(ship);
    shipId = ApexPages.currentPage().getParameters().get('shipId');
    if (shipid == null) {
        ship = new Shipment__c();
    return;
}

ship = [select id, location__c, tracking_number__c
                from shipment__c
                where id = :shipid];
}
public PageReference prepareShipment() {
    ship.tracking_Number__c = Wrapper.tnumber;
    ship.Location__c = Wrapper.location;
    update ship;  

VF snippet:

   <apex:page  controller="shipmentController" showHeader="true" 
   sidebar="true">
   <apex:form >
   <apex:pageBlock Title="edit Shipment">
   <apex:pageMessages />
<apex:pageBlockSection Title="Shipment Information" columns="2">
<apex:inputText label="First Name" value="{!wrapper.tNumber}" 
 id="fname"/>
   <apex:inputText label="Last Name" value="{!wrapper.location}" 
  id="lname"/>
</apex:pageBlockSection>

Answer 1

You need a public variable that you can reference:

public shipWrapper wrapper { get; set; }

Which you initialize in your constructor:

public shipmentController() {
   ...
   wrapper = new shipmentWrapper(ship);
}

And then can access in prepareShipment:

public PageReference prepareShipment() {
    ship.STracking_Number__c = wrapper.tNumber;
    ...
}

---

Edit: You need to load the record, then initialize the wrapper:

if(shipid == null) {
    ship = new Shipment__c();
} else {
    ship = [select id, location__c, tracking_number__c
                   from shipment__c
                   where id = :shipid];
}
wrapper = new ShippingWrapper(ship);