QT中QTableWidget加载大量数据不卡顿的解决

// item 水平表头自适应大小
	tab->horizontalHeader()->setSectionResizeMode(QHeaderView::Stretch);
	// item 垂直表头自适应大小
	ui->tableWidget->verticalHeader()->setSectionResizeMode(QHeaderView::Stretch);
 	//试着设置为：  QHeaderView::Fixed 看看是否还会卡顿

//需要重写的虚函数
	virtual void wheelEvent(QWheelEvent* event)
	//事件过滤器
	virtual bool eventFilter(QObject* obj, QEvent* event)

void SongMenu::loadData()
{
	int len = taglsit.length();
	for (int i = 0; i != 20; ++i) {
		if (i >= len)return;
		ui->tab_SongTable->insertRow(i);
		//添加窗口小部件
		ui->tab_SongTable->setCellWidget(i, 0, base->setItemWidget(1));
		QTableWidgetItem* item1 = new QTableWidgetItem(taglsit.at(i).Title);
		QTableWidgetItem* item2 = new QTableWidgetItem(taglsit.at(i).Artist);
		QTableWidgetItem* item3 = new QTableWidgetItem(taglsit.at(i).Ablue);
		QTableWidgetItem* item4 = new QTableWidgetItem(taglsit.at(i).Duration);
		ui->tab_SongTable->setItem(i, 1, item1);
		ui->tab_SongTable->setItem(i, 2, item2);
		ui->tab_SongTable->setItem(i, 3, item3);
		ui->tab_SongTable->setItem(i, 4, item4);
	}
	curtableindex = 20;
	//下面例子是加载大量数据会卡顿，原因:一次性把所有的数据都添加了且设置了自适应宽度
	/*foreach(const Temptag & rhs, taglsit) {
		ui->tab_SongTable->insertRow(index);
		ui->tab_SongTable->setCellWidget(index, 0, base->setItemWidget(1));
		QTableWidgetItem* item1 = new QTableWidgetItem(rhs.Artist);
		QTableWidgetItem* item2 = new QTableWidgetItem(rhs.Title);
		QTableWidgetItem* item3 = new QTableWidgetItem(rhs.Ablue);
		QTableWidgetItem* item4 = new QTableWidgetItem(rhs.Duration);
		ui->tab_SongTable->setItem(index, 1, item1);
		ui->tab_SongTable->setItem(index, 2, item2);
		ui->tab_SongTable->setItem(index, 3, item3);
		ui->tab_SongTable->setItem(index, 4, item4);
	}*/
}

virtual void wheelEvent(QWheelEvent* event)

void Base::wheelEvent(QWheelEvent* event)
{
	//滑动一次 y() == 120
	//y() > 0 鼠标滚轮向前滑动， y() < 0 鼠标滚轮向自己滑动
	if (event->angleDelta().y() < 0) {
		emit loadNextPage();
	}
}

virtual bool eventFilter(QObject* obj, QEvent* event)

bool Base::eventFilter(QObject* obj, QEvent* event)
{
	if (obj == tab) {
		if (event->type() == QEvent::Wheel) {
			QWheelEvent* wheel = static_cast<QWheelEvent*>(event);
			//y() < 0 鼠标滚轮向自己滑动 
			if (wheel->angleDelta().y() < 0) {
				//发射信号，然后处理数据
				emit loadNextPage(); 
			}
		}
	}
	return QTableWidget::eventFilter(obj,event);
}
//然后在 构造函数中安装事件过滤器
ui->tab_SongTable->installEventFilter(this);

//加载剩余的数据
	connect(base, &Base::loadNextPage, this, [&]() {
	//每次滚动到底部都加载5条数据，和前面一样，检查边界，以防越界
		for (int i = 0; i != 5; i++) {
			if (curtableindex >= taglsit.length()) {
				return;
			}
			else
			{
				//拿到ui->tab_SongTable尾部的索引，之后往尾部添加数据
				int currow = ui->tab_SongTable->rowCount();
				ui->tab_SongTable->insertRow(currow);
				ui->tab_SongTable->setCellWidget(currow, 0, base->setItemWidget(1));
				QTableWidgetItem* item1 = new QTableWidgetItem(taglsit.at(currow).Title);
				QTableWidgetItem* item2 = new QTableWidgetItem(taglsit.at(currow).Artist);
				QTableWidgetItem* item3 = new QTableWidgetItem(taglsit.at(currow).Ablue);
				QTableWidgetItem* item4 = new QTableWidgetItem(taglsit.at(currow).Duration);
				ui->tab_SongTable->setItem(currow, 1, item1);
				ui->tab_SongTable->setItem(currow, 2, item2);
				ui->tab_SongTable->setItem(currow, 3, item3);
				ui->tab_SongTable->setItem(currow, 4, item4);
			}
			//累加索引，防止越界
			++curtableindex ;
		}
		});