基于QAbstractTableModel 实现自定义model ,实现数据的增加,删除,修改并更新表格 C++代码

以下是一个基于QAbstractTableModel的自定义model的示例代码，实现了数据的增加、删除、修改和更新表格。

// mytablemodel.h
#ifndef MYTABLEMODEL_H
#define MYTABLEMODEL_H

#include <QAbstractTableModel>
#include <QVector>

class MyTableModel : public QAbstractTableModel
{
public:
    MyTableModel(QObject *parent = nullptr);

    // 重载QAbstractTableModel的方法
    int rowCount(const QModelIndex &parent = QModelIndex()) const override;
    int columnCount(const QModelIndex &parent = QModelIndex()) const override;
    QVariant data(const QModelIndex &index, int role = Qt::DisplayRole) const override;
    bool setData(const QModelIndex &index, const QVariant &value, int role = Qt::EditRole) override;
    QVariant headerData(int section, Qt::Orientation orientation, int role = Qt::DisplayRole) const override;
    Qt::ItemFlags flags(const QModelIndex &index) const override;

    // 自定义方法
    bool insertRow(int row, const QModelIndex &parent = QModelIndex());
    bool removeRow(int row, const QModelIndex &parent = QModelIndex());
    void setTableData(const QVector<QVector<QString>> &data);

private:
    QVector<QVector<QString>> m_tableData;
};

#endif // MYTABLEMODEL_H

// mytablemodel.cpp
#include "mytablemodel.h"

MyTableModel::MyTableModel(QObject *parent)
    : QAbstractTableModel(parent)
{
}

int MyTableModel::rowCount(const QModelIndex &parent) const
{
    Q_UNUSED(parent)
    return m_tableData.size();
}

int MyTableModel::columnCount(const QModelIndex &parent) const
{
    Q_UNUSED(parent)
    if (m_tableData.isEmpty())
        return 0;
    return m_tableData[0].size();
}

QVariant MyTableModel::data(const QModelIndex &index, int role) const
{
    if (!index.isValid())
        return QVariant();

    if (role == Qt::DisplayRole || role == Qt::EditRole) {
        int row = index.row();
        int column = index.column();
        return m_tableData[row][column];
    }

    return QVariant();
}

bool MyTableModel::setData(const QModelIndex &index, const QVariant &value, int role)
{
    if (index.isValid() && role == Qt::EditRole) {
        int row = index.row();
        int column = index.column();
        m_tableData[row][column] = value.toString();
        emit dataChanged(index, index, { role });
        return true;
    }

    return false;
}

QVariant MyTableModel::headerData(int section, Qt::Orientation orientation, int role) const
{
    if (orientation == Qt::Horizontal && role == Qt::DisplayRole) {
        return QString("Column %1").arg(section);
    }

    if (orientation == Qt::Vertical && role == Qt::DisplayRole) {
        return QString("Row %1").arg(section);
    }

    return QVariant();
}

Qt::ItemFlags MyTableModel::flags(const QModelIndex &index) const
{
    if (!index.isValid())
        return Qt::NoItemFlags;
    return Qt::ItemIsEditable | QAbstractTableModel::flags(index);
}

bool MyTableModel::insertRow(int row, const QModelIndex &parent)
{
    beginInsertRows(parent, row, row);
    QVector<QString> rowData(columnCount());
    m_tableData.insert(row, rowData);
    endInsertRows();
    return true;
}

bool MyTableModel::removeRow(int row, const QModelIndex &parent)
{
    beginRemoveRows(parent, row, row);
    m_tableData.remove(row);
    endRemoveRows();
    return true;
}

void MyTableModel::setTableData(const QVector<QVector<QString>> &data)
{
    m_tableData = data;
    emit layoutChanged();
}

使用示例：

// main.cpp
#include <QApplication>
#include <QTableView>
#include "mytablemodel.h"

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);

    QVector<QVector<QString>> data = {
        { "1", "Tom", "20" },
        { "2", "Jack", "25" },
        { "3", "Lucy", "18" }
    };

    MyTableModel model;
    model.setTableData(data);

    QTableView tableView;
    tableView.setModel(&model);
    tableView.show();

    return a.exec();
}

以上代码实现了一个简单的表格，包括三列：编号、姓名和年龄。可以通过调用`insertRow()`、`removeRow()`和`setData()`方法来增加、删除和修改表格中的数据，表格会自动更新。