qt实现绘图工具栏，具体ui

下面是一个使用Qt实现绘图工具栏的示例代码：

// mainwindow.h
#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include <QToolBar>
#include <QComboBox>
#include <QAction>
#include <QColorDialog>

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    MainWindow(QWidget *parent = nullptr);
    ~MainWindow();

private slots:
    void onPenColorChanged();
    void onBrushColorChanged();

private:
    QToolBar *toolBar;
    QComboBox *penColorComboBox;
    QComboBox *brushColorComboBox;
    QAction *penColorAction;
    QAction *brushColorAction;
};

#endif // MAINWINDOW_H


// mainwindow.cpp
#include "mainwindow.h"

MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
{
    // 创建绘图工具栏
    toolBar = new QToolBar(this);

    // 创建画笔颜色选择框
    penColorComboBox = new QComboBox(this);
    penColorComboBox->addItem("Black", QColor(Qt::black));
    penColorComboBox->addItem("Red", QColor(Qt::red));
    penColorComboBox->addItem("Green", QColor(Qt::green));
    penColorComboBox->addItem("Blue", QColor(Qt::blue));
    connect(penColorComboBox, SIGNAL(currentIndexChanged(int)), this, SLOT(onPenColorChanged()));

    // 创建画刷颜色选择框
    brushColorComboBox = new QComboBox(this);
    brushColorComboBox->addItem("No brush", QColor(Qt::transparent));
    brushColorComboBox->addItem("Yellow", QColor(Qt::yellow));
    brushColorComboBox->addItem("Cyan", QColor(Qt::cyan));
    brushColorComboBox->addItem("Magenta", QColor(Qt::magenta));
    connect(brushColorComboBox, SIGNAL(currentIndexChanged(int)), this, SLOT(onBrushColorChanged()));

    // 创建动作
    penColorAction = toolBar->addWidget(penColorComboBox);
    brushColorAction = toolBar->addWidget(brushColorComboBox);

    // 将工具栏添加到主窗口
    addToolBar(toolBar);
}

MainWindow::~MainWindow()
{
}

void MainWindow::onPenColorChanged()
{
    QComboBox *comboBox = qobject_cast<QComboBox*>(sender());
    if (comboBox)
    {
        QColor color = comboBox->currentData().value<QColor>();
        // 更新画笔颜色
        // ...
    }
}

void MainWindow::onBrushColorChanged()
{
    QComboBox *comboBox = qobject_cast<QComboBox*>(sender());
    if (comboBox)
    {
        QColor color = comboBox->currentData().value<QColor>();
        // 更新画刷颜色
        // ...
    }
}

这是一个简单的绘图工具栏示例，其中包括画笔颜色选择框和画刷颜色选择框。你可以根据需要添加其他绘图工具和功能。注意，这只是一个示例，具体实现可能需要根据你的需求进行调整。