Important form methods in Dynamics 365 for Finance and Operations

[Form]
public class POLMobileServiceTable extends FormRun
{
[DataSource]
class POLMobileServiceTable
{
/// /// ///
public void executeQuery()
{
//Before the query executes
//(select * from POLMobileServiceTable where ServiceStatus = InReview

        this.query().dataSourceTable(tableNum(POLMobileServiceTable)).addRange(
            fieldNum(POLMobileServiceTable, ServiceStatus)).value(queryValue(POLServiceStatus::InReview));

        super(); //Actual query execution (select * from POLMobileServiceTable)
        //After the query executes
    }

}

[DataSource]
class POLMobileServiceTable
{
    /// <summary>
    ///
    /// </summary>
    /// <returns></returns>
    public int active()
    {
        int ret;

        ret = super();

        POLUpdateAsDelivered.enabled(POLMobileServiceTable.ServiceStatus == POLServiceStatus::Repaired);

        return ret;
    }
} 

}