Qt教程之QSqlQueryModel的使用详解

#ifndef WIDGET_H
#define WIDGET_H
 
#include <QWidget>
#include <QSqlQueryModel>
#include <QSqlQuery>
#include <QSqlDatabase>
#include <QDataWidgetMapper>
#include "ComboBoxDelegate.h"
#include "SpinBoxDelegate.h"
#include <QModelIndex>
 
namespace Ui {
class Widget;
}
 
class Widget : public QWidget
{
    Q_OBJECT
 
public:
    explicit Widget(QWidget *parent = 0);
    ~Widget();
 
private:
    void initTableView();
 
private slots:
    void on_btnOpen_clicked();
 
    void on_tableView_clicked(const QModelIndex &index);
 
    void on_btnAdd_clicked();
 
    void on_btnDel_clicked();
 
private:
    Ui::Widget *ui;
 
private:
    QSqlQueryModel *m_model = nullptr;
 
    ComboBoxDelegate m_cbxDelegate;
 
    SpinBoxDelegate m_spinDelegate;
 
    QSqlDatabase m_db;
 
    QDataWidgetMapper *m_dataMapper = nullptr;
};
 
#endif // WIDGET_H

#include "widget.h"
#include "ui_widget.h"
#include <QFileDialog>
#include <QDebug>
#include <QSqlRecord>
 
Widget::Widget(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::Widget)
{
    ui->setupUi(this);
 
    ui->tableView->verticalHeader()->setHidden(true);
 
    ui->tableView->setSelectionBehavior(QAbstractItemView::SelectRows);
 
    ui->tableView->setSelectionMode(QAbstractItemView::SingleSelection);
 
    ui->tableView->setAlternatingRowColors(true);
 
    this->resize(1000,600);
}
 
Widget::~Widget()
{
    delete ui;
}
 
void Widget::initTableView()
{
    //数据表model
    m_model = new QSqlQueryModel(this);
 
    //查询数据
    m_model->setQuery("select id,name,sex,age,addr,height from students");
 
    m_model->setHeaderData(0,Qt::Horizontal,"编号");
    m_model->setHeaderData(1,Qt::Horizontal,"姓名");
    m_model->setHeaderData(2,Qt::Horizontal,"性别");
    m_model->setHeaderData(3,Qt::Horizontal,"年龄");
    m_model->setHeaderData(4,Qt::Horizontal,"地址");
    m_model->setHeaderData(5,Qt::Horizontal,"身高");
 
    //设置模型
    ui->tableView->setModel(m_model);
 
    //设置性别代理
    ui->tableView->setItemDelegateForColumn(2,&m_cbxDelegate);
 
    //设置年龄代理
    ui->tableView->setItemDelegateForColumn(3,&m_spinDelegate);
 
    //创建界面组件与数据模型的字段之间的数据映射
    m_dataMapper = new QDataWidgetMapper(this);
 
    //设置数据模型
    m_dataMapper->setModel(m_model);
 
    m_dataMapper->setSubmitPolicy(QDataWidgetMapper::AutoSubmit);
 
    //界面组件与tabModel的具体字段之间的联系
    m_dataMapper->addMapping(ui->spinBoxNum,0);
    m_dataMapper->addMapping(ui->lineEditName,1);
    m_dataMapper->addMapping(ui->cbxSex,2);
    m_dataMapper->addMapping(ui->spinBoxAge,3);
    m_dataMapper->addMapping(ui->lineEditAddr,4);
    m_dataMapper->addMapping(ui->doubleSpinBoxHeight,5);
 
    //移动到首记录
    m_dataMapper->toFirst();
}
 
 
void Widget::on_btnOpen_clicked()
{
    QString file = QFileDialog::getOpenFileName(this,"选择数据库文件","",
                                               "SQLite数据库(*.db *.db3)");
    if(file.isEmpty())
        return;
 
    m_db = QSqlDatabase::addDatabase("QSQLITE");
    m_db.setDatabaseName(file);
 
    if(!m_db.open())
    {
        qDebug()<<"打开失败";
        return;
    }
 
    initTableView();
}
 
void Widget::on_tableView_clicked(const QModelIndex &index)
{
    m_dataMapper->setCurrentIndex(index.row());
}
 
void Widget::on_btnAdd_clicked()
{
    QSqlQuery query;
    query.prepare("insert into students (id,name,sex,age,addr,height)"
                  "values(:ID,:Name,:Sex,:Age,:Addr,:Height)");
 
    query.bindValue(":ID",20);
    query.bindValue(":Name","马超");
    query.bindValue(":Sex","男");
    query.bindValue(":Age",27);
    query.bindValue(":Addr","蜀国");
    query.bindValue(":Height",1.76);
 
    if(!query.exec())
        return;
}
 
void Widget::on_btnDel_clicked()
{
    QModelIndex curIndex = ui->tableView->currentIndex();
 
    //获取当前记录
    QSqlRecord curRec = m_model->record(curIndex.row());
 
    if(curRec.isEmpty())
        return;
 
    //获取id
    int id = curRec.value("id").toInt();
 
    QSqlQuery query;
    query.prepare("delete from students where id = :ID");
    query.bindValue(":ID",id);
 
    if(!query.exec())
        return;
}