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   源码介绍

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Qt轮播图实现，在一个机会下，面试官让我写一个Qt轮播图功能的项目，所以我就把它传到这供大家参考，我认为功能还是比较全的，笔者把一些功能都是写活的，并且有非常详实的注释，比较适合初学者对信号槽机制的掌握，也方便大家使用。我个人认为Qt的轮播图确实很考验一个开发者使用信号槽机制的使用情况。

 里面的注释也写的挺全的，希望对大家有所帮助~~

/*
 * LKYSlidesShow轮播 1.0
 * L·K`Y
 * 2020.11.13   02:33
 * Cheer Up!!!
 */
#include "lkyslidesshow.h"
#include <QLayoutItem>
#include <QVBoxLayout>
#include <QHBoxLayout>
#include <QMessageBox>
#include <QDebug>
LKYSlidesShow::LKYSlidesShow(QWidget *parent) : QWidget(parent)
{
    m_turnLeft = true;                  //轮播方向
    m_navTextVisible = false;           //显示导航器序号
    m_mouseHoverStop = false;           //是否鼠标悬停
    m_mouseNavHoverChange = false;      //是否鼠标悬停导航器按钮时图片切换
    m_navType = Rectangle;              //导航器样式
    m_navPos = Left;                    //导航器位置
    m_navBtnSize = QSize(30, 24);       //导航器按钮大小
    m_navTextColor = Qt::black;         //导航器序号颜色
    m_navColor = QColor(128, 128, 128); //导航器颜色
    m_navHoverColor = Qt::yellow;       //导航器悬停颜色
    m_navPressColor = Qt::green;        //导航器按下颜色
    m_curIndex = 0;                     //当前图片索引
    m_preIndex = 0;                     //之前图片索引
    m_offsetX = 0;                      //图片偏移量
    m_changePixmapInterVal = 3000;      //图片切换间隔（图片轮换间隔，包含了图片动画间隔，单位：毫秒）
    m_PixmapAnimationInterval = 1000;   //图片移动间隔（图片动画间隔，单位：毫秒）


    initForm();
    //初始化定时器
    m_timer = new QTimer(this);
    m_timer->setInterval(m_changePixmapInterVal);
    connect(m_timer,SIGNAL(timeout()),this,SLOT(onTimeout()));
    //初始化动画
    m_animation = new QPropertyAnimation(this, "offsetX");
    m_animation->setDuration(m_PixmapAnimationInterval);

    this->setMouseTracking(true);
    this->setAttribute(Qt::WA_Hover, true);
}

void LKYSlidesShow::setPixmapAnimationInterval(int msecs)
{
    m_PixmapAnimationInterval = msecs;
}

void LKYSlidesShow::setPlayDir(bool turnLeft)
{
    m_turnLeft = turnLeft;
}

void LKYSlidesShow::setPixmap(const QList<QPixmap *> &pixmaps)
{
    //停止定时器、停止动画
    if (m_timer->isActive())
        m_timer->stop();
    if (m_animation->state() == QAbstractAnimation::Running)
        m_animation->stop();

    //清空数据
    qDeleteAll(m_pixmaps);

    m_pixmaps.clear();
    m_btns.clear();

    //清空布局中的数据
    QLayoutItem *child;

    while ((child = m_hNavLayout->takeAt(0)) != nullptr)
    {
        QWidget *widget = child->widget();
        delete widget;
        delete child;
    }

    //赋值数据
    m_pixmaps = pixmaps;
    for(int i = 0; i < pixmaps.count(); i  )
    {
        QPushButton *btn = new QPushButton(QString::number(i   1));
        btn->setFixedWidth(30);
        m_hNavLayout->addWidget(btn);
        m_btns.append(btn);
        connect(btn,SIGNAL(clicked()), this, SLOT(onClicked()));
        btn->installEventFilter(this);
    }


    m_curIndex = m_preIndex = 0;

    setNavType(m_navType);
    setNavPos(m_navPos);
    m_timer->start();
    //图片切换时，发送图片索引
    emit currentIndexChange(m_curIndex);
    update();
}

void LKYSlidesShow::setNavType(NavType navType)
{
    m_navType = navType;
    for (int i = 0; i < m_btns.count(); i  )
    {
        QString qss = "";
        QPushButton *btn = m_btns.at(i);
        //控制导航器序号显示与否
        if (m_navTextVisible)
            btn->setText(QString::number(i   1));
        else
            btn->setText("");

        //控制导航器样式
        if (navType == Rectangle)
        {
            btn->setFixedSize(m_navBtnSize);
            if (i == m_curIndex)
            {
                qss = QString("QPushButton{border:none; background-color:rgb(%1, %2, %3); color:rgb(%4, %5, %6);}\
                                QPushButton:hover{border:none; background-color:rgb(%7, %8, %9); color:rgb(%4, %5, %6)}\
                                QPushButton:pressed{border:none; background-color:rgb(%1, %, %3); color:rgb(%4, %5, %6)}")
                              .arg(m_navPressColor.red()).arg(m_navPressColor.green()).arg(m_navPressColor.blue())
                              .arg(m_navTextColor.red()).arg(m_navTextColor.green()).arg(m_navTextColor.blue())
                              .arg(m_navHoverColor.red()).arg(m_navHoverColor.green()).arg(m_navHoverColor.blue());
            }
            else
            {
                qss = QString("QPushButton{border:none; background-color:rgb(%1, %2, %3); color:rgb(%4, %5, %6);}\
                                QPushButton:hover{border:none; background-color:rgb(%7, %8, %9); color:rgb(%4, %5, %6)}\
                                QPushButton:pressed{border:none; background-color:rgb(%10, %11, %12); color:rgb(%4, %5, %6)}")
                              .arg(m_navColor.red()).arg(m_navColor.green()).arg(m_navColor.blue())
                              .arg(m_navTextColor.red()).arg(m_navTextColor.green()).arg(m_navTextColor.blue())
                              .arg(m_navHoverColor.red()).arg(m_navHoverColor.green()).arg(m_navHoverColor.blue())
                              .arg(m_navPressColor.red()).arg(m_navPressColor.green()).arg(m_navPressColor.blue());
            }
        }
        else if (navType == RoundedRectangle)
        {
            btn->setFixedSize(m_navBtnSize);
            if (i == m_curIndex)
            {
                qss = QString("QPushButton{border:none; border-radius:5px; background-color:rgb(%1, %2, %3); color:rgb(%4, %5, %6);}\
                                QPushButton:hover{border:none; background-color:rgb(%7, %8, %9); color:rgb(%4, %5, %6)}\
                                QPushButton:pressed{border:none; background-color:rgb(%1, %, %3); color:rgb(%4, %5, %6)}")
                              .arg(m_navPressColor.red()).arg(m_navPressColor.green()).arg(m_navPressColor.blue())
                              .arg(m_navTextColor.red()).arg(m_navTextColor.green()).arg(m_navTextColor.blue())
                              .arg(m_navHoverColor.red()).arg(m_navHoverColor.green()).arg(m_navHoverColor.blue());
            }
            else
            {
                qss = QString("QPushButton{border:none; border-radius:5px; background-color:rgb(%1, %2, %3); color:rgb(%4, %5, %6);}\
                                QPushButton:hover{border:none; background-color:rgb(%7, %8, %9); color:rgb(%4, %5, %6)}\
                                QPushButton:pressed{border:none; background-color:rgb(%10, %11, %12); color:rgb(%4, %5, %6)}")
                              .arg(m_navColor.red()).arg(m_navColor.green()).arg(m_navColor.blue())
                              .arg(m_navTextColor.red()).arg(m_navTextColor.green()).arg(m_navTextColor.blue())
                              .arg(m_navHoverColor.red()).arg(m_navHoverColor.green()).arg(m_navHoverColor.blue())
                              .arg(m_navPressColor.red()).arg(m_navPressColor.green()).arg(m_navPressColor.blue());
            }
        }
        else if (navType == Circle)
        {
            //将用户设定的导航器按钮设置为正方形，用于设置样式为正圆
            int len = qMin(m_navBtnSize.width(), m_navBtnSize.height());
            len = len % 2 == 0 ? len : len   1;
            btn->setFixedSize(len ,len);
            if (i == m_curIndex)
            {
                qss = QString("QPushButton{border:none; border-radius:%1px; background-color:rgb(%2, %3, %4); color:rgb(%5, %6, %7);}\
                                QPushButton:hover{border:none; background-color:rgb(%8, %9, %10); color:rgb(%5, %6, %7)}\
                                QPushButton:pressed{border:none; background-color:rgb(%2, %3, %4); color:rgb(%5, %6, %7)}")
                              .arg(len / 2)
                              .arg(m_navPressColor.red()).arg(m_navPressColor.green()).arg(m_navPressColor.blue())
                              .arg(m_navTextColor.red()).arg(m_navTextColor.green()).arg(m_navTextColor.blue())
                              .arg(m_navHoverColor.red()).arg(m_navHoverColor.green()).arg(m_navHoverColor.blue());
            }
            else
            {
                qss = QString("QPushButton{border:none; border-radius:%1px; background-color:rgb(%2, %3, %4); color:rgb(%5, %6, %7);}\
                                QPushButton:hover{border:none; border-radius:%1px; background-color:rgb(%8, %9, %10); color:rgb(%5, %6, %7)}\
                                QPushButton:pressed{border:none; border-radius:%1px; background-color:rgb(%11, %12, %13); color:rgb(%5, %6, %7)}")
                              .arg(len / 2)
                              .arg(m_navColor.red()).arg(m_navColor.green()).arg(m_navColor.blue())
                              .arg(m_navTextColor.red()).arg(m_navTextColor.green()).arg(m_navTextColor.blue())
                              .arg(m_navHoverColor.red()).arg(m_navHoverColor.green()).arg(m_navHoverColor.blue())
                              .arg(m_navPressColor.red()).arg(m_navPressColor.green()).arg(m_navPressColor.blue());
            }
        }
        else if (navType == ConCentric_circle)
        {
            //将用户设定的导航器按钮设置为正方形，用于设置样式为正圆
            int len = qMin(m_navBtnSize.width(), m_navBtnSize.height());
            len = len % 2 == 0 ? len : len   1;
            btn->setFixedSize(len, len);
            if (i == m_curIndex)
            {
                qss = QString("QPushButton{border:none; border-radius:%1px; background-color:qradialgradient(cx:0.5, cy:0.5, radius:0.5, fx:0.5, fy:0.5, stop:0 rgb(%2, %3, %4), stop:0.4 rgb(%2, %3, %4), stop:0.6 transparent, stop:1 rgb(%2, %3, %4)); color:rgb(%5, %6, %7);}\
                                QPushButton:hover{border:none; background-color:qradialgradient(cx:0.5, cy:0.5, radius:0.5, fx:0.5, fy:0.5, stop:0 rgb(%8, %9, %10), stop:0.4 rgb(%8, %9, %10), stop:0.6 transparent, stop:1 rgbrgb(%8, %9, %10)); color:rgb(%5, %6, %7)}\
                                QPushButton:pressed{border:none; background-color:qradialgradient(cx:0.5, cy:0.5, radius:0.5, fx:0.5, fy:0.5, stop:0 rgb(%2, %3, %4), stop:0.4 rgb(%2, %3, %4), stop:0.6 transparent, stop:1 rgb(%2, %3, %4)); color:rgb(%5, %6, %7)}")
                              .arg(len / 2)
                              .arg(m_navPressColor.red()).arg(m_navPressColor.green()).arg(m_navPressColor.blue())
                              .arg(m_navTextColor.red()).arg(m_navTextColor.green()).arg(m_navTextColor.blue())
                              .arg(m_navHoverColor.red()).arg(m_navHoverColor.green()).arg(m_navHoverColor.blue());
            }
            else
            {
                qss = QString("QPushButton{border:none; border-radius:%1px; background-color:qradialgradient(cx:0.5, cy:0.5, radius:0.5, fx:0.5, fy:0.5, stop:0 rgb(%2, %3, %4), stop:0.4 rgb(%2, %3, %4), stop:0.6 transparent, stop:1 rgb(%2, %3, %4)); color:rgb(%5, %6, %7);}\
                                QPushButton:hover{border:none; background-color:qradialgradient(cx:0.5, cy:0.5, radius:0.5, fx:0.5, fy:0.5, stop:0 rgb(%8, %9, %10), stop:0.4 rgb(%8, %9, %10), stop:0.6 transparent, stop:1 rgbrgb(%8, %9, %10)); color:rgb(%5, %6, %7)}\
                                QPushButton:pressed{border:none; background-color:qradialgradient(cx:0.5, cy:0.5, radius:0.5, fx:0.5, fy:0.5, stop:0 rgb(%11, %12, %13), stop:0.4 rgb(%11, %12, %13), stop:0.6 transparent, stop:1 rgb(%11, %12, %13)); color:rgb(%5, %6, %7)}")
                              .arg(len / 2)
                              .arg(m_navColor.red()).arg(m_navColor.green()).arg(m_navColor.blue())
                              .arg(m_navTextColor.red()).arg(m_navTextColor.green()).arg(m_navTextColor.blue())
                              .arg(m_navHoverColor.red()).arg(m_navHoverColor.green()).arg(m_navHoverColor.blue())
                              .arg(m_navPressColor.red()).arg(m_navPressColor.green()).arg(m_navPressColor.blue());
            }

        }
        else if (navType == Ellipse)
        {
            btn->setFixedSize(m_navBtnSize);
            if (i == m_curIndex)
            {
                qss = QString("QPushButton{border:none; border-radius:%1px %2px; background-color:rgb(%3, %4, %5); color:rgb(%6, %7, %8);}\
                                QPushButton:hover{border:none; border-radius:%1px %2px; background-color:rgb(%9, %10, %11); color:rgb(%6, %7, %8)}\
                                QPushButton:pressed{border:none; border-radius:%1px %2px; background-color:rgb(%3, %4, %5); color:rgb(%6, %7, %8)}")
                              .arg(m_navBtnSize.width() / 2).arg(m_navBtnSize.height() / 2)
                              .arg(m_navPressColor.red()).arg(m_navPressColor.green()).arg(m_navPressColor.blue())
                              .arg(m_navTextColor.red()).arg(m_navTextColor.green()).arg(m_navTextColor.blue())
                              .arg(m_navHoverColor.red()).arg(m_navHoverColor.green()).arg(m_navHoverColor.blue());
            }
            else
            {
                qss = QString("QPushButton{border:none; border-radius:%1px %2px; background-color:rgb(%3, %4, %5); color:rgb(%6, %7, %8);}\
                                QPushButton:hover{border:none; border-radius:%1px %2px; background-color:rgb(%9, %10, %11); color:rgb(%6, %7, %8)}\
                                QPushButton:pressed{border:none; border-radius:%1px %2px; background-color:rgb(%12, %13, %14); color:rgb(%6, %7, %8)}")
                              .arg(m_navBtnSize.width() / 2).arg(m_navBtnSize.height() / 2)
                              .arg(m_navColor.red()).arg(m_navColor.green()).arg(m_navColor.blue())
                              .arg(m_navTextColor.red()).arg(m_navTextColor.green()).arg(m_navTextColor.blue())
                              .arg(m_navHoverColor.red()).arg(m_navHoverColor.green()).arg(m_navHoverColor.blue())
                              .arg(m_navPressColor.red()).arg(m_navPressColor.green()).arg(m_navPressColor.blue());
            }
        }
        else if (m_navType == AnimationEllipse)
        {

            if (i == m_curIndex)
            {
                btn->setFixedSize(m_navBtnSize.width() * 2, m_navBtnSize.height());
                qss = QString("QPushButton{border:none; border-radius:%1px %2px; background-color:rgb(%3, %4, %5); color:rgb(%6, %7, %8);}\
                                QPushButton:hover{border:none; border-radius:%1px %2px; background-color:rgb(%9, %10, %11); color:rgb(%6, %7, %8)}\
                                QPushButton:pressed{border:none; border-radius:%1px %2px; background-color:rgb(%3, %4, %5); color:rgb(%6, %7, %8)}")
                              .arg(m_navBtnSize.width() / 2).arg(m_navBtnSize.height() / 2)
                              .arg(m_navPressColor.red()).arg(m_navPressColor.green()).arg(m_navPressColor.blue())
                              .arg(m_navTextColor.red()).arg(m_navTextColor.green()).arg(m_navTextColor.blue())
                              .arg(m_navHoverColor.red()).arg(m_navHoverColor.green()).arg(m_navHoverColor.blue());
            }
            else
            {
                btn->setFixedSize(m_navBtnSize);
                qss = QString("QPushButton{border:none; border-radius:%1px %2px; background-color:rgb(%3, %4, %5); color:rgb(%6, %7, %8);}\
                                QPushButton:hover{border:none; border-radius:%1px %2px; background-color:rgb(%9, %10, %11); color:rgb(%6, %7, %8)}\
                                QPushButton:pressed{border:none; border-radius:%1px %2px; background-color:rgb(%12, %13, %14); color:rgb(%6, %7, %8)}")
                              .arg(m_navBtnSize.width() / 2).arg(m_navBtnSize.height() / 2)
                              .arg(m_navColor.red()).arg(m_navColor.green()).arg(m_navColor.blue())
                              .arg(m_navTextColor.red()).arg(m_navTextColor.green()).arg(m_navTextColor.blue())
                              .arg(m_navHoverColor.red()).arg(m_navHoverColor.green()).arg(m_navHoverColor.blue())
                              .arg(m_navPressColor.red()).arg(m_navPressColor.green()).arg(m_navPressColor.blue());
            }
        }
        btn->setStyleSheet(qss);
    }
}

void LKYSlidesShow::setNavPos(LKYSlidesShow::NavPos navPos)
{
    m_navPos = navPos;
    if (navPos == Left)
    {
        m_hLayout->setStretch(0, 0);
        m_hLayout->setStretch(1, 1);
        m_hLayout->setStretch(2, 6);
    }
    else if (navPos == Center)
    {
        m_hLayout->setStretch(0, 3);
        m_hLayout->setStretch(1, 1);
        m_hLayout->setStretch(2, 3);
    }
    else if(navPos == Right)
    {
        m_hLayout->setStretch(0, 6);
        m_hLayout->setStretch(1, 1);
        m_hLayout->setStretch(2, 0);
    }
}

void LKYSlidesShow::setNavTextVisible(bool textVisible)
{
    m_navTextVisible = textVisible;
    setNavType(m_navType);
}

void LKYSlidesShow::setMouseNavHoverChange(bool mouseNavHoverChange)
{
    m_mouseNavHoverChange = mouseNavHoverChange;
}

void LKYSlidesShow::paintEvent(QPaintEvent *event)
{
    Q_UNUSED(event);

    //判断是否有图片载入
    if(m_pixmaps.count() <= 0)
    {
        m_timer->stop();
        return;
    }

    int width = this->width();
    int height = this->height();
    QPainter painter(this);
    painter.setRenderHints(QPainter::Antialiasing | QPainter::TextAntialiasing);

    if (m_turnLeft)
    {   //向左轮播
        QRect preRect = QRect(-m_offsetX, 0, width, height);
        QRect curRect = QRect(width - m_offsetX, 0, width, height);
        painter.drawPixmap(preRect, *(m_pixmaps.at(m_preIndex)));
        painter.drawPixmap(curRect, *(m_pixmaps.at(m_curIndex)));
    }
    else
    {   //向右轮播
        QRect preRect = QRect(m_offsetX, 0, width, height);
        QRect curRect = QRect(-width   m_offsetX, 0, width, height);
        painter.drawPixmap(preRect, *(m_pixmaps.at(m_preIndex)));
        painter.drawPixmap(curRect, *(m_pixmaps.at(m_curIndex)));
    }
}

bool LKYSlidesShow::eventFilter(QObject *obj, QEvent *ev)
{
    if (obj->metaObject()->className() == QStringLiteral("QPushButton"))
    {
        if(ev->type() == QEvent::HoverEnter)
        {
            if(m_mouseNavHoverChange)
            {
                if(m_timer->isActive())
                    m_timer->stop();

                m_preIndex = m_curIndex;
                m_curIndex = m_btns.indexOf((QPushButton *)obj);

                setNavType(m_navType);
                m_animation->setStartValue(0);
                m_animation->setEndValue(width());
                //图片切换时，发送图片索引
                emit currentIndexChange(m_curIndex);
                update();
            }
        }
        else if (ev->type() == QEvent::HoverLeave)
        {
            if (!m_timer->isActive() || !m_mouseHoverStop)
                m_timer->start();
        }
    }

    return false;
}

void LKYSlidesShow::initForm()
{
    //导航窗体内部布局
    m_navWidget = new QWidget(this);
    m_hNavLayout = new QHBoxLayout(m_navWidget);
    m_hNavLayout->setSpacing(2);
    m_hNavLayout->setMargin(0);
    m_navWidget->setLayout(m_hNavLayout);

    //页面底部导航器整体布局
    m_hLayout = new QHBoxLayout();
    m_lSpacerItem = new QSpacerItem(10, 10, QSizePolicy::Expanding,QSizePolicy::Minimum);
    m_rSpacerItem = new QSpacerItem(10, 10, QSizePolicy::Expanding,QSizePolicy::Minimum);
    m_hLayout->addItem(m_lSpacerItem);
    m_hLayout->addWidget(m_navWidget);
    m_hLayout->addItem(m_rSpacerItem);
    m_hLayout->setStretch(0, 3);
    m_hLayout->setStretch(1, 1);
    m_hLayout->setStretch(2, 3);
    m_hLayout->setSpacing(3);
    m_hLayout->setMargin(0);

    //图片页整体布局
    QVBoxLayout *vLayout = new QVBoxLayout(this);
    m_vSpacerItem = new QSpacerItem(10, 100, QSizePolicy::Minimum, QSizePolicy::Expanding);
    vLayout->addItem(m_vSpacerItem);
    vLayout->addLayout(m_hLayout);
    vLayout->setStretch(0, 6);
    vLayout->setStretch(1, 1);
    vLayout->setSpacing(0);
    vLayout->setMargin(0);
    this->setLayout(vLayout);
}

void LKYSlidesShow::setOffsetX(int offsetX)
{
    m_offsetX = offsetX;
    if (m_navType == AnimationEllipse)
    {
        for (int i = 0;i < m_btns.count();i  )
        {
            if(i == m_curIndex)
            {
                m_btns.at(i)->setFixedWidth(m_navBtnSize.width() * (1   offsetX * 1.0 / width()));
            }
            else
            {
                m_btns.at(i)->setFixedSize(m_navBtnSize);
            }
        }
    }
    update();
}

int LKYSlidesShow::getOffsetX() const
{
    return m_offsetX;
}

void LKYSlidesShow::on_Click_Piece()
{
    if(m_pixmaps.count() == 0)
    {
        QMessageBox::critical(NULL, "hinit", "Please select the picture file first", QMessageBox::Yes | QMessageBox::No, QMessageBox::Yes);
        return;
    }
    m_curIndex--;
    if(m_curIndex < 0)
    {
        m_curIndex = m_pixmaps.count()-1;
    }
    setNavType(m_navType);

    //重新开启定时器
    m_timer->start();
    m_turnLeft = false;
    emit currentIndexChange(m_curIndex);

    update();
}

void LKYSlidesShow::onClicked()
{
    if(!m_mouseNavHoverChange)
    {
        //点击相应按钮，从当前点击按钮图片开始继续轮播
        QPushButton *btn = dynamic_cast<QPushButton *>(sender());
        if(btn != nullptr)
        {
            int index = m_btns.indexOf(btn);
            m_curIndex = m_preIndex = index;
            m_offsetX = 0;
            //停止定时器及动画，防止刚点击新的图片时，由于之前的定时器快到了，直接触发到下一张图片
            m_timer->stop();
            m_animation->stop();
            setNavType(m_navType);
            if(!m_mouseHoverStop)
            {
                //重新开启定时器
                m_timer->start();
            }
            //图片切换时，发送图片索引
            emit currentIndexChange(m_curIndex);
            update();
        }
    }
}


void LKYSlidesShow::on_Click_Next()
{
    if(m_pixmaps.count() == 0)
    {
        QMessageBox::critical(NULL, "hinit", "Please select the picture file first", QMessageBox::Yes | QMessageBox::No, QMessageBox::Yes);
        return;
    }
    m_curIndex  ;
    //从第一张调到最后一张
    if(m_curIndex > m_pixmaps.count()-1)
    {
        m_curIndex = 0;
    }
    setNavType(m_navType);
    m_timer->start();
    m_turnLeft = true;
    emit currentIndexChange(m_curIndex);
    update();
}

void LKYSlidesShow::onTimeout()
{
    m_preIndex = m_curIndex;
    m_curIndex  ;
    //到最后一张Index再重新更新为第一张
    if(m_curIndex == m_pixmaps.count())
        m_curIndex = 0;

    setNavType(m_navType);
    m_animation->setStartValue(0);
    m_animation->setEndValue(width());
    m_animation->start();
    //图片切换时，发送图片索引
    emit currentIndexChange(m_curIndex);
    update();
}