【Qt】重写QComboBox下拉展示多列数据

需求

点击QComboBox时，下拉列表以多行多列的表格展示出来。

实现

直接上代码：

#include <QComboBox>
#include <QTableWidget>
#include <QVBoxLayout>
#include <QWidget>
#include <QEvent>
#include <QMouseEvent>
#include <QLineEdit>
class ComboBoxWithTableWidget : public QComboBox {Q_OBJECTpublic:ComboBoxWithTableWidget(QWidget *parent = nullptr) : QComboBox(parent) {// 隐藏默认的下拉箭头setEditable(true);lineEdit()->setReadOnly(true);// 创建一个隐藏的容器来存放我们的表格popupWidget = new QWidget(this);popupWidget->setWindowFlags(Qt::Popup | Qt::FramelessWindowHint);QVBoxLayout *layout = new QVBoxLayout(popupWidget);layout->setContentsMargins(0, 0, 0, 0);layout->setSpacing(0);tableWidget = new QTableWidget(5, 2, popupWidget); // 5行2列for (int row = 0; row < 5; ++row){for (int col = 0; col < 2; ++col){QTableWidgetItem *item = new QTableWidgetItem(QString("Item %1%2").arg(row).arg(col));tableWidget->setItem(row, col, item);}}tableWidget->setSelectionBehavior(QAbstractItemView::SelectRows);tableWidget->setSelectionMode(QAbstractItemView::SingleSelection);layout->addWidget(tableWidget);popupWidget->resize(220,200);connect(tableWidget, &QTableWidget::cellClicked, this, &ComboBoxWithTableWidget::onCellClicked);popupWidget->hide();}protected:void showPopup() override{if (popupWidget->isHidden()){QComboBox::showPopup();//popupWidget->resize(this->width(), tableWidget->height() + 2); //（可能需要调整）popupWidget->move(this->mapToGlobal(QPoint(0, this->height())));popupWidget->show();tableWidget->setFocus();}}void hidePopup() override{if (popupWidget->isVisible()){popupWidget->hide();QComboBox::hidePopup();}}private slots:void onCellClicked(int row, int column){QString text = tableWidget->item(row, column)->text();this->setCurrentText(text);hidePopup(); // 选择后隐藏下拉列表}private:QWidget *popupWidget = nullptr;QTableWidget *tableWidget= nullptr;
};

示例效果