How do I set a Lookup field for an Asset name via a Visualforce page

Question

I am creating a new Case via a VF page in a VF+Tabs Community (not using SFDC stylesheets) and want the user to be able to set the Asset Name to the Asset related to their new Case. The Asset Name is a Lookup Field.

I have a Controller Extension and VF and that shows the current logged in user a list of all of their Asset Names for them to choose one for their Case.

I am stuck on how to use their selection for the {!Case.Asset.Name} field. I am not able to just write that value to the {!Case.Asset.Name} field since it is a Lookup field.

How do I set the value of the {!Case.Asset.Name} field based on the users selection from the list of Asset Names they have been presented with?

Is there a better way to present them with the list of Asset Names via a Lookup directly on my VF page that will set the value of that field when submitting that new Case?

Here is the Controller Extension I am currently using:

public class myWeb2CaseExtension {
    public Case webcase {get;set;}
    public SelectOption[] assetOptions {get;set;} 

    public myWeb2CaseExtension(ApexPages.StandardController stdController) {

        webcase = (Case) stdController.getRecord();

        User[] users = [SELECT ContactId FROM User WHERE Id = :UserInfo.getUserId()];
        User usr = users[0];

        Contact[] contacts = [SELECT Id, AccountId FROM Contact WHERE Id = :usr.ContactId];

        if (contacts.isEmpty()) {
            // handle when contacts is empty
        } else {
            Contact cont = contacts[0];
            Asset[] assets = [SELECT Name, ContactId, AccountId FROM Asset WHERE AccountId = :cont.AccountId];
            assetOptions = new SelectOption[] {};
            //if you want people to be able to choose no asset do this
            assetOptions.add(new SelectOption('None', 'None'));

            for (Asset asst: assets) {
                assetOptions.add(new SelectOption(asst.Id, asst.Name));                
            } 
        }
    }
    public PageReference saveCase() {
        try {
            Database.DMLOptions dmlOpts = new Database.DMLOptions();
            dmlOpts.assignmentRuleHeader.useDefaultRule = true;
            webcase.setOptions(dmlOpts);
            webcase.Origin = 'Web';
            insert(webcase);
        } catch (System.DMLException e) {
            ApexPages.addMessages(e);
            return null;
        }
        PageReference p = Page.MyCases;
        p.setRedirect(true);
        return p;
    }
 }

Here is the section of my Visualforce page that currently lists the Asset names from the code in the Controller Extension

   <apex:selectList value="{!Case.Asset.Name}" size="7" >
   <apex:selectOptions value="{!assetOptions}" />
   </apex:selectList>

PROBLEM SOLVED : I solved my problem by replacing the Visualforce code mentioned above with the following code in my Visualforce page

 <apex:selectList value="{!Case.AssetId}" size="7" >
   <apex:selectOptions value="{!assetOptions}" />
   </apex:selectList>

Answer 1

You're asking how to set the lookup field based on the user's input, correct? You mention setting the lookup field and then you mention setting the name of the Asset, which are different. I want to make sure you understand this difference before you attempt to change the existing code. Setting the lookup field is a mutation to Case, while changing the name is a mutation to Asset.

Pass the name as a string to your controller and pull the true Asset record using SOQL in your controller, selecting based on a name match, e.g. [SELECT id, name FROM Asset WHERE name =:passedAssetName] and then just assign the ID to your case.