处理控件滚动条事件的例子（QListWidget QListView等）

#include<QListWidget>
#include<QScrollBar>
#include<QWidget>

class Widget:public QWidget
{
    Q_OBJECT
    public:
          Widget(QWidget* parent =0);
    private:
          QListWidget *listWidget;
          QScrollBar *verticalScrollBar;
    private slots:
          void onScrollBarValueChanged(int);
    signals:
          void signalToEmit();
}

Widget::Widget(QWidget *parent):QWidget(parent)
{
    listWidget =new QListWidget(this);   
    verticalScrollBar = listWidget.verticalScrollBar();
    connect(verticalScrollBar, SIGNAL(valueChanged(int)),this,SLOT(onScrollBarValueChanged(int)));
}

void Widget::onScrollBarValueChanged(int value)
{
    if(value == verticalScrollBar->maximum())
        emit signalToEmit();
}