Qt浅谈之四十五QSplitter实现自由伸缩滑动窗口

一、简介

        最近看到一篇Qt实现伸缩滑动的窗口的文章，但其代码不完整。便在此重新书写了完整的代码，并开源出来。窗口的中央有滑动条可以动态改变子窗口的大小，隐藏的按钮可以快速伸缩子窗口。其效果图如下：

二、详解

1、代码

（1）slidingwindow.h

#ifndef SLIDINGWINDOW_H
#define SLIDINGWINDOW_H

#include <QtGui>

class SlidingWindow : public QWidget
{
    Q_OBJECT

public:
    SlidingWindow(QWidget *parent = 0);
    ~SlidingWindow();

protected:
    void mousePressEvent ( QMouseEvent * event);
    void mouseMoveEvent(QMouseEvent *event);
    void mouseReleaseEvent(QMouseEvent *event);
    void resizeEvent(QResizeEvent *event);
    bool eventFilter(QObject *obj, QEvent *event);

private:
    void setBtnPos();
    void setBtnIcon();

private slots:
    void slotClickedBtn();
    void slotSplitterMoved(int pos, int index);

private:
    QPoint dragPosition;
    bool bPressFlag;
    QSplitter *splitter;
    QFrame *contentFrame;
    QFrame *listFrame;
    QPushButton *pushButton;
    QIcon leftIcon;
    QIcon rightIcon;
};

#endif // SLIDINGWINDOW_H

（2）slidingwindow.cpp

#include "slidingwindow.h"

SlidingWindow::SlidingWindow(QWidget *parent)
    : QWidget(parent, Qt::FramelessWindowHint)
    , bPressFlag(false)
{
    resize(660, 460);
    splitter = new QSplitter(Qt::Horizontal, this);
    splitter->setHandleWidth(1);
    splitter->setStyleSheet("QSplitter::handle{background:#FFFFFF}");
    contentFrame = new QFrame(splitter);
    contentFrame->setStyleSheet("background:#000000");
    contentFrame->resize(475, height());
    contentFrame->setMinimumWidth(405);
    listFrame = new QFrame(splitter);
    listFrame->setStyleSheet("background:#323232");
    listFrame->resize(660 - 475, height());
    listFrame->setMaximumWidth(660 - 405);
    connect(splitter, SIGNAL(splitterMoved(int,int)), this, SLOT(slotSplitterMoved(int,int)));

    leftIcon = QIcon(":/left.png");
    rightIcon = QIcon(":/right.png");

    pushButton = new QPushButton(this);
    pushButton->setFocusPolicy(Qt::NoFocus);
    pushButton->hide();
    pushButton->setFixedSize(13, 42);
    pushButton->setIconSize(pushButton->size());
    pushButton->setStyleSheet("border:none;");
    pushButton->setIcon(rightIcon);
    pushButton->move(contentFrame->width() - pushButton->width()-2, (contentFrame->height() - pushButton->height())/2);
    connect(pushButton,SIGNAL(clicked()),this,SLOT(slotClickedBtn()));

    contentFrame->setMouseTracking(true);
    listFrame->setMouseTracking(true);
    contentFrame->installEventFilter(this);
    listFrame->installEventFilter(this);
}

SlidingWindow::~SlidingWindow()
{

}

void SlidingWindow::resizeEvent(QResizeEvent *event)
{
    splitter->setGeometry(0, 0, width(), height());
    move((QApplication::desktop()->width() - width())/2,  (QApplication::desktop()->height() - height())/2);
    QWidget::resizeEvent(event);
}

bool SlidingWindow::eventFilter(QObject *obj, QEvent *event)
{
    if (event->type() == QEvent::MouseMove) {
        QMouseEvent *mouseMove = static_cast<QMouseEvent*>(event);
        QRect rect = pushButton->frameGeometry();
        if (rect.contains(mouseMove->pos())) {
            pushButton->show();
        }
        else {
            pushButton->hide();
        }
    }
    return QWidget::eventFilter(obj, event);
}

void SlidingWindow::setBtnPos()
{
    pushButton->move(contentFrame->width() - pushButton->width(), (contentFrame->height() - pushButton->height())/2);
}

void SlidingWindow::setBtnIcon()
{
    if (listFrame->width() != 0) {
        pushButton->setIcon(rightIcon);
    }
    else {
        pushButton->setIcon(leftIcon);
    }
}

void SlidingWindow::slotClickedBtn()
{
    QList <int> sizeList;
    sizeList.clear();
    if (listFrame->width() != 0) {
        sizeList.append(660);
        sizeList.append(0);
    }
    else {
        sizeList.append(475);
        sizeList.append(660 - 475);
    }
    splitter->setSizes(sizeList);

    setBtnIcon();
    setBtnPos();
    pushButton->hide();
}

void SlidingWindow::slotSplitterMoved(int pos, int index)
{
    Q_UNUSED(pos)
    Q_UNUSED(index)
    setBtnIcon();
    setBtnPos();
}

void SlidingWindow::mousePressEvent ( QMouseEvent * event)
{
    bPressFlag = true;
    dragPosition = event->pos();
    QWidget::mousePressEvent(event);
}

void SlidingWindow::mouseMoveEvent(QMouseEvent *event)
{
    if (bPressFlag) {
        QPoint relaPos(QCursor::pos() - dragPosition);
        move(relaPos);
    }
    QWidget::mouseMoveEvent(event);
}

void SlidingWindow::mouseReleaseEvent(QMouseEvent *event)
{
    bPressFlag = false;
    QWidget::mouseReleaseEvent(event);
}

（3）main.cpp

#include "slidingwindow.h"
#include <QApplication>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    SlidingWindow w;
    w.show();

    return a.exec();
}

（4）编译运行

三、总结

（1）获取位置坐标可以尝试QPoint realPos(QCursor::pos() - this->pos());，这样不用类型转换。主要设置setMouseTracking(true);才能当鼠标不点击时移动鼠标进入mouseMoveEvent事件函数。
（2）源码已上传到csdn：http://download.csdn.net/detail/taiyang1987912/9439233。
（3）若有问题或建议，请留言，在此感谢！