Qt 组合框QComboBox定制颜色选择框

在项目开发中需要定制Qt Combobox,每一项是显示一个RGB颜色供用户选择，实现的效果

QColorCombobox.h

#pragma once
#include <QLineEdit>
#include <QCombobox>

class QLabel;
class QListWidget;

class QColorWidget : public QLineEdit
{
Q_OBJECT
public:
    QColorWidget(QWidget *parent = Q_NULLPTR);
    ~QColorWidget();

    void updateColor(const QColor& color);

    void mousePressEvent(QMouseEvent *event);

signals:
    void click(const QColor& color);
private:
    QLabel* m_pLabel;
    QLabel* m_pRgbLabel;
    QColor m_color;
};

class QColorCombobox :public QComboBox 
{
    Q_OBJECT
public:
    QColorCombobox(QWidget *parent = Q_NULLPTR);
    ~QColorCombobox();

    void appendItem(const QColor& color);

private slots:
    void onClickColorWidget(const QColor& color);
private:
    QColorWidget* m_pLineEdit;
    QListWidget* m_pListWidget;
};

QColorCombobox.cpp

#include "QColorCombobox.h"
#include <QLabel>
#include <QHBoxLayout>
#include <QListWidget>

QColorWidget::QColorWidget(QWidget *parent /*= Q_NULLPTR*/)
    :QLineEdit(parent)
    ,m_color(255,0,0)
{
    m_pLabel = new QLabel(this);
    m_pRgbLabel = new QLabel(this);

    m_pLabel->setFixedSize(15, 15);

    QHBoxLayout* layout = new QHBoxLayout();
    layout->addWidget(m_pLabel);
    layout->addWidget(m_pRgbLabel);
    layout->setContentsMargins(5, 0, 0, 2);
    setLayout(layout);
    setReadOnly(true);

    setStyleSheet("border: none");
}


QColorWidget::~QColorWidget()
{

}

void QColorWidget::updateColor(const QColor& color)
{
    m_color = color;

    QString strstyle = QString("border:1px solid black;background-color:rgb(%1,%2,%3);").arg(QString::number(color.red()), QString::number(color.green()), QString::number(color.blue()));
    QString strText = QString("%1,%2,%3").arg(QString::number(color.red()), QString::number(color.green()), QString::number(color.blue()));
    m_pLabel->setStyleSheet(strstyle);
    m_pRgbLabel->setText(strText);
}

void QColorWidget::mousePressEvent(QMouseEvent *event)
{
    emit click(m_color);
}




QColorCombobox::QColorCombobox(QWidget *parent /*= Q_NULLPTR*/)
    :QComboBox(parent)
{
    m_pLineEdit = new QColorWidget(this);
    m_pListWidget = new QListWidget(this);
    setContextMenuPolicy(Qt::NoContextMenu);//禁用菜单
    m_pListWidget->setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);//禁用垂直滚动条
    m_pListWidget->setStyleSheet("QListWidget::Item:hover{background-color:rgb(0,125,255);}");
    setLineEdit(m_pLineEdit);
    setModel(m_pListWidget->model());
    setView(m_pListWidget);

}

QColorCombobox::~QColorCombobox()
{
}

void QColorCombobox::appendItem(const QColor& color)
{
    QColorWidget* pWid = new QColorWidget(this);
    pWid->updateColor(color);
    connect(pWid, SIGNAL(click(const QColor&)),this,SLOT(onClickColorWidget(const QColor&)));
    QListWidgetItem* pItem = new QListWidgetItem(m_pListWidget);
    
    m_pListWidget->addItem(pItem);
    m_pListWidget->setItemWidget(pItem, pWid);

}

void QColorCombobox::onClickColorWidget(const QColor& color)
{
    m_pLineEdit->updateColor(color);
    hidePopup();
}

MainWindow.cpp

....

    ui.comboBox->appendItem(QColor(255, 0, 0));
    ui.comboBox->appendItem(QColor(255, 255, 0));
    ui.comboBox->appendItem(QColor(255, 0, 255));
    ui.comboBox->appendItem(QColor(0, 255, 255));
    ui.comboBox->appendItem(QColor(0, 255, 0));

...