QT实现按钮滚动的效果

布满荆棘的人生 2022-09-04 05:56 199阅读 0赞

# 1.效果展示 #

![20210811172359586.gif][]

# 2.代码展示 #

代码中已添加了详细的注释，如果看不懂，可以留言。

## 2.1 MyBtnLayout.h  ##

#pragma once
    
    #include <QtWidgets/QMainWindow>
    #include "ui_MyBtnLayout.h"
    #include "QVector"
    
    class MyBtnLayout : public QMainWindow
    {
        Q_OBJECT
    
    public:
        MyBtnLayout(QWidget *parent = Q_NULLPTR);
        
    public slots:
        void AddButton();
        void MoveToLeft();//点击左移按钮后调用此函数
        void MoveToRight();//点击右移按钮后调用此函数
    
    private:
        Ui::MyBtnLayoutClass ui;
        QVector<QPushButton*> m_vctBtn;//保存每个按钮的指针，供后续移动使用
        int m_iBtnNum;//按钮个数
        QSize m_usedSize;//已绘制按钮的区域尺寸
        QSize m_btnAreaSize;//用于放置按钮的整个QWidget的尺寸
        QPushButton *m_btnLeft;//左移按钮
        QPushButton *m_btnRight;//右移按钮
        bool m_bShowMoveBtn;//是否已显示出左移和右移按钮
    };

## 2.2 MyBtnLayout.cpp ##

#include "MyBtnLayout.h"
    #include "QPushButton"
    
    MyBtnLayout::MyBtnLayout(QWidget *parent)
        : QMainWindow(parent)
    {
        ui.setupUi(this);   
        setWindowFlags(Qt::FramelessWindowHint);
    
        //响应添加按钮的点击事件
        connect(ui.pushButton,SIGNAL(clicked()),this,SLOT(AddButton()));
    
        m_iBtnNum = 0;
        m_usedSize = QSize(0, 0);
        m_btnAreaSize = ui.widget->size();
        m_bShowMoveBtn = false;    
    }
    
    void MyBtnLayout::AddButton()
    {    
        //创建和保存按钮
        QString strBtnText = QString("BTN%1").arg(m_iBtnNum);
        QPushButton *btn = new QPushButton(strBtnText, ui.widget);
        m_vctBtn.push_back(btn);
    
        //设置按钮尺寸和移动位置
        btn->setFixedSize(100, m_btnAreaSize.height());
        if (m_usedSize == QSize(0, 0))
        {
            btn->move(0, 0);
        }
        else
        {
            btn->move(m_usedSize.width(), 0);
        }
    
        //计算下次按钮显示位置的相关参数的值
        m_usedSize += btn->size();
        m_usedSize.setWidth(m_usedSize.width());
        m_iBtnNum++;
        btn->show();
    
        //如果已经添加的按钮在ui.widget放不下时，则创建和显示左移、右移按钮，并且要调整其它按钮的位置
        if (!m_bShowMoveBtn && (m_usedSize.width() > m_btnAreaSize.width()))
        {        
            for (int i = 0;i < m_vctBtn.size();i++)
            {
                m_vctBtn[i]->move(m_vctBtn[i]->x() + 50,0);
            }
    
            m_usedSize.setWidth(m_usedSize.width() + 50);
    
            m_btnLeft = new QPushButton("<<", ui.widget);
            m_btnLeft->setGeometry(0, 0, 50, m_btnAreaSize.height());
            m_btnRight = new QPushButton(">>", ui.widget);
            m_btnRight->setGeometry(m_btnAreaSize.width() - 49, 0, 50, m_btnAreaSize.height());
            m_btnLeft->show();
            m_btnRight->show();
            m_bShowMoveBtn = true;
    
            connect(m_btnLeft, SIGNAL(clicked()),this,SLOT(MoveToLeft()));
            connect(m_btnRight, SIGNAL(clicked()), this, SLOT(MoveToRight()));
        }
    }
    
    void MyBtnLayout::MoveToLeft()
    {
        for (int i = 0; i < m_vctBtn.size(); i++)
        {
            m_vctBtn[i]->move(m_vctBtn[i]->x() - 50, 0);
        }
    
        m_usedSize.setWidth(m_usedSize.width() - 50);
    }
    
    void MyBtnLayout::MoveToRight()
    {
        for (int i = 0; i < m_vctBtn.size(); i++)
        {
            m_vctBtn[i]->move(m_vctBtn[i]->x() + 50, 0);
        }
    
        m_usedSize.setWidth(m_usedSize.width() + 50);
    }

[20210811172359586.gif]: /images/20220829/952f4b256dd44311b87306ee22ad09b4.png