Hi All,
I have created a custom object Student__c. Now the problem i am having is object of Student__c is not getting called in the vf page. I am not able to understadn the reason. if i create a variable and call that it's working.

Below is my apex code.
public class DemoClass {
 String countries = '';

    public List<Student__c> stu {get;set;}
    public String fname{get;set;}
     
    public Student__c student = new Student__c(First_name__c = '2212121212121');
          
    public DemoClass(){
        stu = [select name,First_name__c, Last_Name__c,Age__c,Sex__c from Student__c limit 10];
        //student = new Student__c();
        
    }
    
    public PageReference test() {
        return null;
    }
            
    public Student__c getstudent(){
        return student;
    }
    public List<SelectOption> getItems() {
        List<SelectOption> options = new List<SelectOption>();
        /* options.add(new SelectOption('US','USA'));
options.add(new SelectOption('CANADA','Canada'));
options.add(new SelectOption('MEXICO','Mexico'));
*/
        for(Student__c temp:stu){
            options.add(new SelectOption(String.valueOf(temp.ID),temp.name));
        }            
        return options;
    }
    
    public String getCountries() {
        student = getS();fname=student.First_name__c;
        student.First_name__c = '222222';
        return countries;
    }
    
    public void setCountries(String countries) {
        setS((ID)countries);
        this.countries = countries;
    }
    
     public Student__c getS() {
           // countries = 'asdasda';
            System.debug('x154865 the loop'+student);
            return student;
        }
    public void setS(ID rec) {
        //  countries = '11111';
        Student__c temp1 = null;
        System.debug('before the loop '+ rec);
        for(Student__c temp:stu){
            if(rec==temp.id){
                System.debug('inside the loop '+ rec);
                temp1=temp;
            }
        }
        this.student = temp1;
        System.debug('X154865'+temp1+' - '+this.student);
    }

}

VF page
<apex:page controller="DemoClass"  >
      <apex:form>
        <apex:selectList value="{!countries}" multiselect="false" onchange="func();">
            <apex:selectOptions value="{!items}"/>
        </apex:selectList><p/>
        <apex:actionFunction name="func" action="{!test}" rerender="out" status="status"/>
        <apex:commandButton value="Test" action="{!test}" rerender="out" status="status"/>
         
          <apex:outputPanel id="out"> 
                <apex:inputText  value="{!student.First_Name__c}"/> 
        <apex:actionstatus id="status" startText="testing...">
            <apex:facet name="stop"> 
                <apex:outputPanel>
                    <p>You have selected:</p>
                     
                    <apex:dataList value="{!countries}" var="c">{!c}</apex:dataList>
                    {!student.Name}
                    
                    hi hi hi {!student.ID} {!student.First_name__c}
                    
                    <h1>
          name is               {!fname}
                    </h1>
                </apex:outputPanel>
            </apex:facet>
        </apex:actionstatus>
    </apex:outputPanel>
    </apex:form>

    
    
</apex:page>



Please help me thorugh. Let me know if any further details are required from my end