Qt之QSlider

一、新建QtGUI應用，選取QWidget爲基類，取消建立界面

二、widget.h中

#ifndef WIDGET_H
#define WIDGET_H

#include <QSlider>
#include <QLabel>

class Widget : public QWidget
{
    Q_OBJECT

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

private:
    QSlider *slider[6];
    QLabel *lbl[3];

private slots:
    void valueChanged1(int value);
    void valueChanged2(int value);
    void valueChanged3(int value);

};

#endif // WIDGET_H

widget.cpp中

#include "widget.h"

Widget::Widget(QWidget *parent)
    : QWidget(parent)
{
    int xpos = 20, ypos = 20;
    for(int i = 0 ; i < 6 ; i++)
    {
        if(i <= 2)
        {
            slider[i] = new QSlider(Qt::Vertical, this);
            slider[i]->setGeometry(xpos, 20, 30, 80);
            xpos += 30;
        }
        else if(i >= 3)
        {
            slider[i] = new QSlider(Qt::Horizontal, this);
            slider[i]->setGeometry(130, ypos, 80, 30);
            ypos += 30;
        }

        slider[i]->setRange(0, 100);
        slider[i]->setValue(50);
    }

    xpos = 20;
    for(int i = 0 ; i < 3 ; i++)
    {
        lbl[i] = new QLabel(QString("%1").arg(slider[i]->value()), this);
        lbl[i]->setGeometry(xpos+10, 100, 30, 40);
        xpos += 30;
    }

    connect(slider[0], SIGNAL(valueChanged(int)), this,
                       SLOT(valueChanged1(int)));

    connect(slider[1], SIGNAL(valueChanged(int)), this,
                       SLOT(valueChanged2(int)));

    connect(slider[2], SIGNAL(valueChanged(int)), this,
                       SLOT(valueChanged3(int)));
}

void Widget::valueChanged1(int value)
{
    lbl[0]->setText(QString("%1").arg(value));
    slider[3]->setValue(slider[0]->value());
}

void Widget::valueChanged2(int value)
{
    lbl[1]->setText(QString("%1").arg(value));
    slider[4]->setValue(slider[1]->value());
}

void Widget::valueChanged3(int value)
{
    lbl[2]->setText(QString("%1").arg(value));
    slider[5]->setValue(slider[2]->value());
}

Widget::~Widget()
{

}

效果：