Question

如何实时取得QSpinBox的值

Answer 1

　　自己emit一个信号，步骤如下(保证你这个两个cpp都对应的类是继承自QObject类)：
　　准备两个cpp,一个是包含QSpinBox的cpp，一个是需要获得SpinBox改变的值
　　1、在QSpinBox的类中（可能是QWidget）中增加一个信号void spinBoxChanged(QString);
　　2、对于一个QSpinBox会有一个valueChanged的信号槽，假设你已经实现了这个槽函数中，并且在这个槽函数中得到了改变后的值，然后emit spinBoxChanged(changeValue);
　　3、再在另一个需要获得SpinBox的cpp对应的类（假设是QClass）中增加一个与信号函数的参数相同的槽函数
　　void slotSpinBoxChanged(QString).并实现之
　　4、连接两个对象的信号和槽，一般在初始化中连接

　　可能写的不太好懂，为了简单，你可以利用QT的一个信号对应多个槽的机制，不需要自己发信号，直接把槽函数和QSpinBox的valueChanged信号相连，这样就更简单了。

Answer 2

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#include <QtGui>

#include "mainwindow.h"
#include <QLabel>
#include <QSplitter>

#include <QHBoxLayout>
#include <QSlider>
#include <QSpinBox>

int spinBox1value;
int spinBox2value;

MainWindow::MainWindow()
: QMainWindow()
{
QSplitter *MainSplitter = new QSplitter(Qt::Horizontal);

area = new SvgWindow;
area->resize(289,maximumHeight ());
area->setStyleSheet("background-color:gray;");
QSplitter * WidgetRight = new QSplitter(Qt::Vertical);
//WidgetRight->setWindowTitle("Enter Your Age");
QWidget *SubWidget1 = new QWidget;
QWidget *SubWidget2 = new QWidget;
////////////////////////////////////////////////////////////////////////////////
QSpinBox *spinBox1 = new QSpinBox;

QSlider *slider1 = new QSlider(Qt::Horizontal);
spinBox1->setRange(0, 130);
slider1->setRange(0, 130);
QObject::connect(spinBox1, SIGNAL(valueChanged(int)),
slider1, SLOT(setValue(int)));
QObject::connect(slider1, SIGNAL(valueChanged(int)),
spinBox1, SLOT(setValue(int)));
QObject::connect(spinBox1, SIGNAL(valueChanged(int)),
this,SLOT(GetValue1(int)));
QObject::connect(spinBox1, SIGNAL(valueChanged(int)),
area,SLOT(SpinBoxEvent(int)));

spinBox1->setValue(35);

QHBoxLayout *layout1 = new QHBoxLayout;
layout1->addWidget(spinBox1);
layout1->addWidget(slider1);
SubWidget1->setLayout(layout1);
////////////////////////////////////////////////////////////////////////////
QSpinBox *spinBox2 = new QSpinBox;
QSlider *slider2 = new QSlider(Qt::Horizontal);
spinBox2->setRange(0, 130);
slider2->setRange(0, 130);
QObject::connect(spinBox2, SIGNAL(valueChanged(int)),
slider2, SLOT(setValue(int)));
QObject::connect(slider2, SIGNAL(valueChanged(int)),
spinBox2, SLOT(setValue(int)));
spinBox2->setValue(35);

QHBoxLayout *layout2 = new QHBoxLayout;
layout2->addWidget(spinBox2);
layout2->addWidget(slider2);
SubWidget2->setLayout(layout2);

/////////////////////////////////////////////////////////////////////////////

WidgetRight->addWidget(SubWidget1);
WidgetRight->addWidget(SubWidget2);

MainSplitter->addWidget(area);
MainSplitter->addWidget(WidgetRight);

setCentralWidget(MainSplitter);

QMenu *fileMenu = new QMenu(tr("&File"), this);
QAction *openAction = fileMenu->addAction(tr("&Open..."));
openAction->setShortcut(QKeySequence(tr("Ctrl+O")));
QAction *quitAction = fileMenu->addAction(tr("E&xit"));
quitAction->setShortcut(QKeySequence(tr("Ctrl+Q")));

menuBar()->addMenu(fileMenu);

QMenu *rendererMenu = new QMenu(tr("&Renderer"), this);
nativeAction = rendererMenu->addAction(tr("&Native"));
nativeAction->setCheckable(true);
nativeAction->setChecked(true);
#ifndef QT_NO_OPENGL
glAction = rendererMenu->addAction(tr("&OpenGL"));
glAction->setCheckable(true);
#endif
imageAction = rendererMenu->addAction(tr("&Image"));
imageAction->setCheckable(true);

QActionGroup *rendererGroup = new QActionGroup(this);
rendererGroup->addAction(nativeAction);
#ifndef QT_NO_OPENGL
rendererGroup->addAction(glAction);
#endif
rendererGroup->addAction(imageAction);

menuBar()->addMenu(rendererMenu);

connect(openAction, SIGNAL(triggered()), this, SLOT(openFile()));
connect(quitAction, SIGNAL(triggered()), qApp, SLOT(quit()));
connect(rendererGroup, SIGNAL(triggered(QAction *)),
this, SLOT(setRenderer(QAction *)));

//setCentralWidget(area);
setWindowTitle(tr("SVG Viewer"));
}

void MainWindow::openFile(const QString &path)
{
QString fileName;
if (path.isNull())
fileName = QFileDialog::getOpenFileName(this, tr("Open SVG File"),
currentPath, "*.svg");
else
fileName = path;

if (!fileName.isEmpty()) {
area->openFile(fileName);
if (!fileName.startsWith(":/")) {
currentPath = fileName;
setWindowTitle(tr("%1 - SVGViewer").arg(currentPath));
}
}
}

void MainWindow::setRenderer(QAction *action)
{
if (action == nativeAction)
area->setRenderer(SvgWindow::Native);
#ifndef QT_NO_OPENGL
else if (action == glAction)
area->setRenderer(SvgWindow::OpenGL);
#endif
else if (action == imageAction)
area->setRenderer(SvgWindow::Image);
}
void MainWindow::GetValue1(int value1)
{
spinBox1value=spinBox1->value();