Hi, I'm pretty new to visualforce development.  I'm currently trying to create a page that will serve as an  update wizard for a parent and child custom object.  I'm getting the following error when trying to reference the child object (Petition__c) in the VF page.

Error: Could not resolve the entity from <apex:inputField> value binding '{!petition.Start_Date__c}'. <apex:inputField> can only be used with SObject fields.

So as it is I can get and update information from the "h2case" but not from the "petition".  I'll post my vf and controller code below.  

<apex:page controller="Testappnotcont">
    <apex:sectionHeader title="Approval Notice Received"/>
        <apex:form >
            <apex:pageBlock title="Update Member Information">
                <apex:pageblockButtons >
                    <apex:commandButton value="Save" action="{!save}"/>
                    <apex:commandButton value="Cancel" action="{!cancel}"/>
                </apex:pageblockButtons>
                    <b>Scan approval notice into company's e-file using the following format </b>
                            <blockquote> <FONT COLOR="#FF0000">Company Name - Approval - Last 5 digits of            the approval notice</FONT> </blockquote>
                <apex:pageBlockSection title="H2Case Information">
                    <b> Update the H2Case status to "Approval Notice Recieved". </b>
                            <apex:inputField value="{! h2case.status__c}"/>
                </apex:pageBlockSection>
                <apex:pageBlockSection title="Petition Information">
                    <p> <b> Make sure that the start and end dates are correct. </b> <br/>
                            <apex:inputField value="{! petition.Start_Date__c}"/> <br/>
                            <apex:inputField value="{! petition.End_Date__c}"/> </p>
                        <b> Number of workers. </b>
                            <apex:inputField value="{! petition.Max_Workers__c}"/>
                        <b> Date USCIS notice received. </b>
                            <apex:inputField value="{! petition.USCIS_Received_Date__c}"/>
                        <b> Petition Number</b> <FONT COLOR="#FF0000">(if not already updated).</FONT>
                            <apex:inputField value="{! petition.name}"/>
                        <b> Update Petition status to "Approved". </b>
                            <apex:inputField value="{! petition.Petition_Status__c}"/>
                        <b> Date the approval notice was received. </b>
                            <apex:inputField value="{! petition.Approval_Notice_Received__c}"/>
                </apex:pageBlockSection>
            </apex:pageBlock>            
        </apex:form>
</apex:page>

public class Testappnotcont
{


    public PageReference cancel() {
        return null;
    }


    public H2B_Case__c h2case {get; set;}
    public List<Petition__c> petition {get; set;} 
    
    public Testappnotcont() {
        String id = ApexPages.currentPage().getParameters().get('id');

        h2case = [select id, Status__c from H2B_Case__c where Id = :id][0];
        petition = [select id, Start_Date__c, End_Date__c, Max_Workers__c, USCIS_Received_Date__c, Name, Petition_Status__c, 
        Approval_Notice_Received__c from Petition__c where H2B_Case__r.Id = :h2case.Id];
    }

    public PageReference save() {
        update h2case;
        update petition;
        return null;
    }

}

Hi, I'm pretty new to visualforce development.  I'm currently trying to create a page that will serve as an  update wizard for a parent and child custom object.  I'm getting the following error when trying to reference the child object (Petition__c) in the VF page.

Error: Could not resolve the entity from <apex:inputField> value binding '{!petition.Start_Date__c}'. <apex:inputField> can only be used with SObject fields.

So as it is I can get and update information from the "h2case" but not from the "petition".  I'll post my vf and controller code below.  

<apex:page controller="Testappnotcont">
    <apex:sectionHeader title="Approval Notice Received"/>
        <apex:form >
            <apex:pageBlock title="Update Member Information">
                <apex:pageblockButtons >
                    <apex:commandButton value="Save" action="{!save}"/>
                    <apex:commandButton value="Cancel" action="{!cancel}"/>
                </apex:pageblockButtons>
                    <b>Scan approval notice into company's e-file using the following format </b>
                            <blockquote> <FONT COLOR="#FF0000">Company Name - Approval - Last 5 digits of            the approval notice</FONT> </blockquote>
                <apex:pageBlockSection title="H2Case Information">
                    <b> Update the H2Case status to "Approval Notice Recieved". </b>
                            <apex:inputField value="{! h2case.status__c}"/>
                </apex:pageBlockSection>
                <apex:pageBlockSection title="Petition Information">
                    <p> <b> Make sure that the start and end dates are correct. </b> <br/>
                            <apex:inputField value="{! petition.Start_Date__c}"/> <br/>
                            <apex:inputField value="{! petition.End_Date__c}"/> </p>
                        <b> Number of workers. </b>
                            <apex:inputField value="{! petition.Max_Workers__c}"/>
                        <b> Date USCIS notice received. </b>
                            <apex:inputField value="{! petition.USCIS_Received_Date__c}"/>
                        <b> Petition Number</b> <FONT COLOR="#FF0000">(if not already updated).</FONT>
                            <apex:inputField value="{! petition.name}"/>
                        <b> Update Petition status to "Approved". </b>
                            <apex:inputField value="{! petition.Petition_Status__c}"/>
                        <b> Date the approval notice was received. </b>
                            <apex:inputField value="{! petition.Approval_Notice_Received__c}"/>
                </apex:pageBlockSection>
            </apex:pageBlock>            
        </apex:form>
</apex:page>

public class Testappnotcont
{


    public PageReference cancel() {
        return null;
    }


    public H2B_Case__c h2case {get; set;}
    public List<Petition__c> petition {get; set;} 
    
    public Testappnotcont() {
        String id = ApexPages.currentPage().getParameters().get('id');

        h2case = [select id, Status__c from H2B_Case__c where Id = :id][0];
        petition = [select id, Start_Date__c, End_Date__c, Max_Workers__c, USCIS_Received_Date__c, Name, Petition_Status__c, 
        Approval_Notice_Received__c from Petition__c where H2B_Case__r.Id = :h2case.Id];
    }

    public PageReference save() {
        update h2case;
        update petition;
        return null;
    }

}