QTableWidget左上角添加按钮

QTableView设置表格左上的文字主要方法是继承后添加按钮

GTableWidget.h

#ifndef GTABLEWIDGET_H
#define GTABLEWIDGET_H


#include <QTableWidget>

class TableWidget : public QTableWidget
{
    Q_OBJECT

public:
    TableWidget(int rows, int cols, QWidget* parent = 0);

    bool eventFilter(QObject* o, QEvent* e);

};


#endif // GTABLEWIDGET_H

#include "GTableWidget.h"

#include <QEvent>
#include <QHeaderView>
#include <QApplication>
#include <QStylePainter>
#include <QAbstractButton>

TableWidget::TableWidget(int rows, int cols, QWidget *parent)
    : QTableWidget(rows, cols, parent)
{
    QAbstractButton* btn = findChild<QAbstractButton*>();

    if (btn)
    {
        btn->setText(QStringLiteral("角落按钮"));
        btn->installEventFilter(this);

        // adjust the width of the vertical header to match the preferred corner button width

        // (unfortunately QAbstractButton doesn't implement any size hinting functionality)

        QStyleOptionHeader opt;
        opt.text = btn->text();
        QSize s = (btn->style()->sizeFromContents(QStyle::CT_HeaderSection, &opt, QSize(), btn).
                   expandedTo(QApplication::globalStrut()));

        if (s.isValid())
        {
            verticalHeader()->setMinimumWidth(s.width());
        }
    }
}


bool TableWidget::eventFilter(QObject *o, QEvent *e)
{
    if (e->type() == QEvent::Paint)
    {
        QAbstractButton* btn = qobject_cast<QAbstractButton*>(o);

        if (btn)
        {
            // paint by hand (borrowed from QTableCornerButton)

            QStyleOptionHeader opt;
            opt.init(btn);
            QStyle::State state = QStyle::State_None;

            if (btn->isEnabled())
            {
                state |= QStyle::State_Enabled;
            }

            if (btn->isActiveWindow())
            {
                state |= QStyle::State_Active;
            }

            if (btn->isDown())
            {
                state |= QStyle::State_Sunken;
            }

            opt.state = state;
            opt.rect = btn->rect();
            opt.text = btn->text(); // this line is the only difference to QTableCornerButton

            opt.position = QStyleOptionHeader::OnlyOneSection;
            QStylePainter painter(btn);
            painter.drawControl(QStyle::CE_Header, opt);
            return true; // eat event
        }
    }

    return false;
}

测试

#include "mainwindow.h"
#include "GTableWidget.h"
#include "ui_mainwindow.h"
#include <QHeaderView>
#include <QVBoxLayout>

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);

    TableWidget *pTableWidget = new TableWidget(3, 3,this);
    pTableWidget->setStyleSheet("QTableCornerButton::section{background-color: red;}");
    pTableWidget->horizontalHeader()->setStyleSheet("QHeaderView::section{background: green}");
    pTableWidget->verticalHeader()->setStyleSheet("QHeaderView::section{background: green}");

    QVBoxLayout *pLayout = new QVBoxLayout(this);
    pLayout->addWidget(pTableWidget);

    ui->centralWidget->setLayout(pLayout);
}

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