QtableView中添加复选框

先创建一个Qt widgets 应用程序，并将mainwindow.cpp文件中修改为如下代码

#include "mainwindow.h"
#include "ui_mainwindow.h"

#include <QMessageBox>
#include <QSqlDatabase>
#include <QDebug>
#include <QSqlError>
#include <QSqlQuery>
#include <QSqlRecord>
#include <QTableView>

#include <QSqlTableModel>

static bool createConnectionDateBase()
{
    QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE");; //创建QSQLdatabase对象，指定QT使用的哪一种SQL。
    db.setDatabaseName("testSQL.db");
    if(!db.open())
    {
        QMessageBox::critical(NULL,"数据库打开失败","打开数据库失败！",
                              QMessageBox::Cancel);
        return false;
    }
    QSqlQuery query;
    query.exec("create table TEST_SQL (id int(1) primary key,name char(200),age int(1),chenked int (1))");

    query.exec("insert into TEST_SQL values(1,'测试1',18,0)");
    query.exec("insert into TEST_SQL values(2,'测试2',19,0)");
    query.exec("insert into TEST_SQL values(3,'测试3',20,0)");
    return true;
}

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    if(!createConnectionDateBase())
    {
        return;
    }

    model = new QSqlTableModel(this);
    model->setTable("TEST_SQL");
    model->setHeaderData(0,Qt::Horizontal,tr("ID号"));
    model->setHeaderData(1,Qt::Horizontal,tr("姓名"));
    model->setHeaderData(2,Qt::Horizontal,tr("年龄"));
    model->select();
    QTableView *view = new QTableView(this);
    view->setModel(model);
    setCentralWidget(view);
    //ui->tableView->setModel(model);

}

MainWindow::~MainWindow()
{
    delete ui;
}

运行查看效果，

 现在开始往这个表中添加复选框，需要继承QSqlTableModel类，在工程中Add new，新建一个C++类，名字为myTableModel，然后在将生成的mytablemodel.h和metaoblemodel.cpp修改为如下：

#ifndef MYTABLEMODEL_H
#define MYTABLEMODEL_H

#include <QtSql>

class myTableModel:public QSqlTableModel
{
    Q_OBJECT
public:
    myTableModel( QObject * parent = 0, QSqlDatabase db = QSqlDatabase() );

    bool setData( const QModelIndex &index, const QVariant &value, int role );
    QVariant data(const QModelIndex &index, int role) const;
    Qt::ItemFlags flags(const QModelIndex &index) const;
};

#endif // MYTABLEMODEL_H

#include "mytablemodel.h"

QMap<int, Qt::CheckState> check_state_map;
int checkColumn = 3;//将复选框放到第几列，从0开始计数

myTableModel::myTableModel(QObject *parent, QSqlDatabase db)
{

}

bool myTableModel::setData(const QModelIndex &index, const QVariant &value, int role)
{
    if(!index.isValid())
        return false;


    if (role == Qt::CheckStateRole && index.column() == checkColumn)
    {
        check_state_map[index.row()] = (value == Qt::Checked ? Qt::Checked : Qt::Unchecked);return true;
    }
    else
        return QSqlTableModel::setData(index, value,role);
}

QVariant myTableModel::data(const QModelIndex &index, int role) const
{
    if (!index.isValid())
        return QVariant();
    if (index.column() != checkColumn )
    {
        return QSqlTableModel::data(index, role);
    }
    switch(role)
    {
        case Qt::CheckStateRole:
        if(index.column() == checkColumn)
        {
            if (check_state_map.contains(index.row()))
            {

                return check_state_map[index.row()] == Qt::Checked ? Qt::Checked : Qt::Unchecked;
            }

            return Qt::Unchecked;
        }
        default:
            return QVariant();
    }
    return QVariant();
}

Qt::ItemFlags myTableModel::flags(const QModelIndex &index) const
{
    if (!index.isValid())
        return 0;
    if (index.column() == checkColumn)
        return Qt::ItemIsEnabled | Qt::ItemIsSelectable | Qt::ItemIsUserCheckable;
    else
        return QSqlTableModel::flags(index);
    return  Qt::ItemIsEnabled | Qt::ItemIsSelectable;
}

然后将mianwindow.cpp中包含该头文件 mytablemodel.h 然后将mianwindow.cpp的构造函数修改为如下：

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    if(!createConnectionDateBase())
    {
        return;
    }

    model = new myTableModel(this);
    model->setTable("TEST_SQL");
    model->setHeaderData(0,Qt::Horizontal,tr("ID号"));
    model->setHeaderData(1,Qt::Horizontal,tr("姓名"));
    model->setHeaderData(2,Qt::Horizontal,tr("年龄"));
    model->select();
    QTableView *view = new QTableView(this);
    view->setModel(model);
    setCentralWidget(view);
    //ui->tableView->setModel(model);

}

然后运行看效果

复选框已经出现在了第3列。

至于怎么知道是否选中呢，

在myTableModel.cpp文件中的check_state_map中， check_state_map[i]的值就是第i行CheckBox的值。