我在更改后更新模型/视图时遇到问题。
为了更好地解释我的意思，我用 SQLite 写了一个简单的例子。
所以 main.cpp 文件：
#include <QApplication>
#include "MainForm.h"
void createConnection()
{
QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE");
db.setDatabaseName("deptemployee.dat");
if (!db.open()) {
QMessageBox::information(0, QObject::tr("Database Error"), db.lastError().text());
db.close();
return;
}
}
void createFakeData()
{
QSqlQuery query;
query.exec("DROP TABLE Department");
query.exec("DROP TABLE Employee");
query.exec("CREATE TABLE Department(id INTEGER PRIMARY KEY AUTOINCREMENT, name VARCHAR(40) NOT NULL)");
query.exec("CREATE TABLE Employee(id INTEGER PRIMARY KEY AUTOINCREMENT, departmentid INTEGER NOT NULL, FOREIGN KEY (departmentid) REFERENCES Department)");
query.exec("INSERT INTO Department(name) VALUES('SomeDepartment')");
query.exec("INSERT INTO Department(name) VALUES('AnotherDepartment')");
query.exec("INSERT INTO Employee(departmentid) VALUES(1)");
query.exec("INSERT INTO Employee(departmentid) VALUES(2)");
}
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
createConnection();
createFakeData();
MainForm form;
form.resize(500, 600);
form.show();
return a.exec();
}
MainForm.h 文件：
#pragma once
#include <QWidget>
#include <QObject>
#include <QtWidgets>
#include <QtSql>
enum {
Employee_Id = 0,
Employee_DepartmentId = 1
};
class MainForm : public QWidget
{
Q_OBJECT
public:
MainForm()
{
model = new QSqlRelationalTableModel(this);
model->setTable("Employee");
model->setRelation(Employee_DepartmentId, QSqlRelation("Department", "id", "name"));
model->select();
view = new QTableView;
view->setModel(model);
view->setItemDelegate(new QSqlRelationalDelegate(this));
addButton = new QPushButton("Add");
connect(addButton, SIGNAL(clicked()), SLOT(addButtonClicked()));
QVBoxLayout* mainLayout = new QVBoxLayout;
mainLayout->addWidget(view);
mainLayout->addWidget(addButton);
setLayout(mainLayout);
model->select();
}
private slots:
void addButtonClicked()
{
int row = model->rowCount();
model->insertRow(row);
QModelIndex index = model->index(row, Employee_DepartmentId);
view->setCurrentIndex(index);
view->edit(index);
}
private:
QPushButton* addButton;
QTableView* view;
QSqlRelationalTableModel* model;
};
那么关于错误......在编辑包含外键的单元格后，显示的值变得错误。因此，例如在部门更改后，它显示为整数而不是字符串。为什么？是Qt错误吗？
添加新行后同样的问题。