Qt Table Widget常用操作

一、鼠标悬浮在item上 显示提示信息

1、在构造函数开启table Widget控件的鼠标捕获功能

// 开启鼠标捕获功能(实现table widget的悬浮功能)
ui.tableWidget->setMouseTracking(true);

2、连接信号和槽

connect(ui.tableWidget, SIGNAL(    cellEntered(int, int)), this, SLOT(slotCellEntered(int, int)));

3、编写槽函数

void test10292::slotCellEntered(int r, int c)
{
    QTableWidgetItem* item = ui.tableWidget->item(r, c);
    if (item == nullptr)
    {
        return;
    }
    QToolTip::showText(QCursor::pos(), item->text());
}

二：点击表头实现排序

第二个是后实现的，按数值排序，因为Qt自带的排序是按 字段排序的

// 连接信号和槽
connect(ui.tableWidget->horizontalHeader(), SIGNAL(sectionClicked(int)), this, SLOT(sortHeader(int)));
// 实现槽函数
void test10292::sortHeader(int index)
{
    if (index == 2)
    {
        ui.tableWidget->sortItems(index, Qt::DescendingOrder);
        return;
    }
    ui.tableWidget->sortItems(index, Qt::AscendingOrder);
}

void test10292::sortHeader(int index)
{
    if (index == 0 || index == 2)
    {
        sortTableItem(index);
        return;
    }
    ui.tableWidget->sortItems(index, Qt::AscendingOrder);
}
// 表头排序
void test10292::sortTableItem(int index)
{
    int rowCountNum = ui.tableWidget->rowCount();
    for (int i =  rowCountNum - 1; i >= 0; i--)
    {
        for (int j = 0; j < i; j++)
        {
            if (ui.tableWidget->item(j, index)->text().toInt() < ui.tableWidget->item(j + 1, index)->text().toInt())
            {
                QString str1 = ui.tableWidget->item(j + 1, 0)->text();
                QString str2 = ui.tableWidget->item(j + 1, 1)->text();
                QString str3 = ui.tableWidget->item(j + 1, 2)->text();
                ui.tableWidget->item(j + 1, 0)->setText(ui.tableWidget->item(j, 0)->text());
                ui.tableWidget->item(j + 1, 1)->setText(ui.tableWidget->item(j, 1)->text());
                ui.tableWidget->item(j + 1, 2)->setText(ui.tableWidget->item(j, 2)->text());
                ui.tableWidget->item(j, 0)->setText(str1);
                ui.tableWidget->item(j, 1)->setText(str2);
                ui.tableWidget->item(j, 2)->setText(str3);
            }
        }
    }
}

三：拖拽item 实现两个item内容的互换

需要写一个类MyQTableWidget继承自QTableWidget，然后重写mousePressEvent和dropEvent事件处理函数

MyQTableWidget.h 文件

#ifndef MYQTABLEWIDGET_H
#define MYQTABLEWIDGET_H

#include <QTableWidget>
#include <QMouseEvent>
#include <QDebug>

class MyQTableWidget : public QTableWidget
{
    Q_OBJECT

public:
    MyQTableWidget(QWidget *parent);
    ~MyQTableWidget();

private:
    QString temp;
    QPoint m_spos, m_dpos;
    QTableWidgetItem* sitem;
    QTableWidgetItem* ditem;
    void mousePressEvent(QMouseEvent *event);
    void dropEvent(QDropEvent *event);
};

#endif // MYQTABLEWIDGET_H

MyQTableWidget.cpp 文件

#include "MyQTableWidget.h"

MyQTableWidget::MyQTableWidget(QWidget *parent)
    :QTableWidget(parent)
{
    /******************** 实现表格控件拖拽item交换数据 ********************/
    this->setDragDropMode(QAbstractItemView::DragDrop);
    this->setDragEnabled(true);
    this->setAcceptDrops(true);
    //选中一个Item
    this->setSelectionBehavior(QAbstractItemView::SelectItems);
}

MyQTableWidget::~MyQTableWidget()
{

}

void MyQTableWidget::mousePressEvent(QMouseEvent *event)
{
    m_spos = event->pos();
    sitem = new QTableWidgetItem();
    sitem = QTableWidget::itemAt(m_spos);
    if (sitem == NULL)
    {
        return;
    }
    temp = sitem->text();
    QTableWidget::mousePressEvent(event);
}

void MyQTableWidget::dropEvent(QDropEvent *event)
{
    m_dpos = event->pos();
    ditem = new QTableWidgetItem();
    ditem = QTableWidget::itemAt(m_dpos);
    if (ditem == NULL)
    {
        return;
    }
    sitem->setText(ditem->text());
    ditem->setText(temp);
}

四：在 item 里面添加CheckBox控件

1、添加选择功能

QTableWidgetItem* item = new QTableWidgetItem();
item = new QTableWidgetItem();
item->setCheckState(Qt::Unchecked);
item->setText(QString::fromLocal8Bit("勾选"));
item->setBackgroundColor(QColor(0x00, 0xFF, 0x00));
ui.tableWidget->setItem(row, 3, item);

2、复选框选择事件处理

// 连接信号和槽
connect(ui.tableWidget, SIGNAL(cellClicked(int, int)), this, SLOT(stateChecked(int, int)));
// 实现槽函数
void test10292::stateChecked(int row, int column )
{
    if (column == 3)
    {
        QTableWidgetItem* item = ui.tableWidget->item(row, column);
        if (item != NULL)
        {
            if (item->checkState() == Qt::Checked)
            {
                // 选中红色
                item->setBackgroundColor(QColor(0xFF, 0x00, 0x00));
            }
            else if (item->checkState() == Qt::Unchecked)
            {
                // 没选中绿色
                item->setBackgroundColor(QColor(0x00, 0xFF, 0x00));
            }
        }
    }
}

 五：插入复选框的第二种方法

QCheckBox* cb = new QCheckBox();
cb->setText(QString::fromLocal8Bit("易语言"));
ui.tableWidget->setCellWidget(row, 3, cb);

 六：其中一个item是CheckBox控件，拖拽实现交换两个item(包括控件交换)

主要是通过 item 的关联数据来实现， 插入数据的时候如果是控件关联数据设置为一个值，不是控件设置为另外一个值。然后在dropEvent()事件函数里面处理。

void test10292::AddData(const QString& id, const QString& name, int score)
{
    int row = ui.tableWidget->rowCount();
    ui.tableWidget->insertRow(row);
    // ID
    QTableWidgetItem* item = new QTableWidgetItem();
    item->setText(id);
    item->setData(Qt::ToolTip, "");
    ui.tableWidget->setItem(row, 0, item);
    item->setTextAlignment(Qt::AlignHCenter|Qt::AlignVCenter);
    // name
    item = new QTableWidgetItem();
    item->setText(name);
    item->setData(Qt::ToolTip, "");
    ui.tableWidget->setItem(row, 1, item);
    item->setTextAlignment(Qt::AlignHCenter|Qt::AlignVCenter);
    // score
    item = new QTableWidgetItem();
    item->setText(QString::number(score));
    item->setData(Qt::ToolTip, "");
    ui.tableWidget->setItem(row, 2, item);
    item->setTextAlignment(Qt::AlignHCenter|Qt::AlignVCenter);
    // 第四列插入复选框
    /*QCheckBox* cb = new QCheckBox();
    cb->setText(QString::fromLocal8Bit("易语言"));
    ui.tableWidget->setCellWidget(row, 3, cb);*/
    item = new QTableWidgetItem();
    item->setCheckState(Qt::Unchecked);
    item->setText(QString::fromLocal8Bit("勾选"));
    item->setBackgroundColor(QColor(0x00, 0xFF, 0x00));
    item->setData(Qt::ToolTip, "this is tooltip");
    ui.tableWidget->setItem(row, 3, item);
}

#include "MyQTableWidget.h"

MyQTableWidget::MyQTableWidget(QWidget *parent)
    :QTableWidget(parent)
{
    /******************** 实现表格控件拖拽item交换数据 ********************/
    this->setDragDropMode(QAbstractItemView::DragDrop);
    this->setDragEnabled(true);
    this->setAcceptDrops(true);
    //选中一个Item
    this->setSelectionBehavior(QAbstractItemView::SelectItems);
}

MyQTableWidget::~MyQTableWidget()
{

}

void MyQTableWidget::mousePressEvent(QMouseEvent *event)
{
    m_spos = event->pos();
    sitem = new QTableWidgetItem();
    sitem = QTableWidget::itemAt(m_spos);
    if (sitem == NULL)
    {
        return;
    }
    temp = sitem->text();
    QTableWidget::mousePressEvent(event);
}

void MyQTableWidget::dropEvent(QDropEvent *event)
{
    m_dpos = event->pos();
    ditem = new QTableWidgetItem();
    ditem = QTableWidget::itemAt(m_dpos);
    if (ditem == NULL)
    {
        return;
    }
    if (sitem->data(Qt::ToolTip).toString() == "this is tooltip" && ditem->data(Qt::ToolTip).toString() == "")
    {
        int r = sitem->row();
        int c = sitem->column();
        delete sitem;
        QTableWidgetItem* itemTemp = new QTableWidgetItem();
        itemTemp->setText(ditem->text());
        itemTemp->setData(Qt::ToolTip, "");
        // 文本背景色设置为白色
        itemTemp->setBackgroundColor(QColor(0xFF, 0xFF, 0xFF));
        itemTemp->setTextAlignment(Qt::AlignHCenter|Qt::AlignVCenter);
        this->setItem(r, c, itemTemp);

        ditem->setText(temp);
        ditem->setCheckState(Qt::Unchecked);
        ditem->setData(Qt::ToolTip, "this is tooltip");
        ditem->setBackgroundColor(QColor(0x00, 0xFF, 0x00));
    }
    else if (sitem->data(Qt::ToolTip).toString() == "this is tooltip" && ditem->data(Qt::ToolTip).toString() == "this is tooltip")
    {
        sitem->setText(ditem->text());
        ditem->setText(temp);
    }
    else if (sitem->data(Qt::ToolTip).toString() == "" && ditem->data(Qt::ToolTip).toString() == "this is tooltip")
    {
        sitem->setText(ditem->text());
        sitem->setCheckState(Qt::Unchecked);
        sitem->setData(Qt::ToolTip, "this is tooltip");
        sitem->setBackgroundColor(QColor(0x00, 0xFF, 0x00));

        int r = ditem->row();
        int c = ditem->column();
        delete ditem;
        QTableWidgetItem* itemTemp = new QTableWidgetItem();
        itemTemp->setText(temp);
        itemTemp->setData(Qt::ToolTip, "");
        // 文本背景色设置为白色
        itemTemp->setBackgroundColor(QColor(0xFF, 0xFF, 0xFF));
        itemTemp->setTextAlignment(Qt::AlignHCenter|Qt::AlignVCenter);
        this->setItem(r, c, itemTemp);
    }
    
    QTableWidget::dropEvent(event);
}