Question

我在CoreData中有一个字典和产品：

import org.hibernate.ejb.HibernatePersistence;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.PropertySource;
import org.springframework.core.env.Environment;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.jdbc.datasource.DriverManagerDataSource;
import org.springframework.orm.jpa.JpaTransactionManager;
import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
import org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter;
import org.springframework.transaction.annotation.EnableTransactionManagement;

import javax.annotation.Resource;
import javax.persistence.EntityManagerFactory;
import javax.sql.DataSource;
import java.util.Properties;

@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(basePackages = {"data"})
@PropertySource("classpath:app.properties")
@ComponentScan(basePackages = {"data.persistence"})
public class DataConfig {
    private static final String PROP_DATABASE_DRIVER = "db.driver";
    private static final String PROP_DATABASE_URL = "db.url";
    private static final String PROP_DATABASE_USERNAME = "db.username";
    private static final String PROP_DATABASE_PASSWORD = "db.password";
    private static final String PROP_HIBERNATE_DIALECT = "db.hibernate.dialect";
    private static final String PROP_HIBERNATE_SHOW_SQL = "db.hibernate.show_sql";
    private static final String PROP_ENTITYMANAGER_PACKAGES_TO_SCAN = "db.entitymanager.packages.to.scan";
    private static final String PROP_HIBERNATE_HBM2DDL_AUTO = "db.hibernate.hbm2ddl.auto";

    @Resource
    private Environment env;

    @Bean
    public DataSource dataSource() {
        DriverManagerDataSource dataSource = new DriverManagerDataSource();

        dataSource.setDriverClassName(env.getRequiredProperty(PROP_DATABASE_DRIVER));
        dataSource.setUrl("jdbc:mysql://localhost:3306/mydb");
        dataSource.setUsername("root");
        dataSource.setPassword("111111");
        return dataSource;
    }

    @Bean
    public LocalContainerEntityManagerFactoryBean entityManagerFactory() {
        LocalContainerEntityManagerFactoryBean entityManager = new LocalContainerEntityManagerFactoryBean();
        entityManager.setDataSource(dataSource());
        entityManager.setPackagesToScan(env.getRequiredProperty(PROP_ENTITYMANAGER_PACKAGES_TO_SCAN));
        entityManager.setPersistenceProviderClass(HibernatePersistence.class);
        entityManager.setJpaVendorAdapter(new HibernateJpaVendorAdapter());
        entityManager.setJpaProperties(getHibernateProperties());
        return entityManager;
    }

    @Bean
    public JpaTransactionManager transactionManager(EntityManagerFactory entityManagerFactory) {
        JpaTransactionManager transactionManager = new JpaTransactionManager();
        transactionManager.setEntityManagerFactory(entityManagerFactory);
        return transactionManager;
    }

    //Set properties hibernate
    private Properties getHibernateProperties() {
        Properties properties = new Properties();
        properties.put("hibernate.dialect", env.getRequiredProperty(PROP_HIBERNATE_DIALECT));
        properties.put("hibernate.show_sql", env.getRequiredProperty(PROP_HIBERNATE_SHOW_SQL));
        properties.put("hibernate.hbm2ddl.auto", env.getRequiredProperty(PROP_HIBERNATE_HBM2DDL_AUTO));

        properties.put("verifyServerCertificate", false);
        properties.put("useSSL", false);
        properties.put("requireSSL", false);
        properties.put("useLegacyDatetimeCode", false);
        properties.put("serverTimezone", "UTC");
        return properties;
    }
}

这是我的numberOfRowsInSection：

var productSortArray: [Date:[Product]?] = [:]
var productArray = [Product]()

当我以commit editStyle删除行时，我会更新：

func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
    return (productSortArray[dateArray[section]]!!.count)
}

但是，当删除行并重新加载表时，行数不正确并出现问题：

更新（1）之后现有节中包含的行数必须等于更新（1）之前该节中包含的行数，加上或减去从该节中插入或删除的行数（已插入0个，删除了1个），再加上或减去移入或移出该部分的行数（移入0，移出0）。'

Answer 1

如果创建真正代表数据的对象，您会发现它比处理数组和字典要容易得多……

struct ProductSection {
    let date: Date
    var products: [Product]
}

var sections: [ProductSection] = // Initialise this

然后

func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
    return sections[section].products.count 
}

然后删除一行...

sections[indexPath.section].remove(at: indexPath.row)
tableView.deleteRows(at: [indexPath], with: .fade)

快速删除元素字典并重新加载tableview

1 个答案: