摘要：
重印地址：https://www.cnblogs.com/ppffs/p/3186221.html最近，由于项目的需要，用Qt开发的程序应该能够支持双屏显示。经过在线研究，我们发现http://www.ics.com/blog/whats-new-qt-5-qscreen-class#.Ud9mY4csnXB中讨论了Qt的多屏幕管理，并指出可以使用QScreen获取窗口的相关信息。代码如下：
转载地址：https://www.cnblogs.com/ppffs/p/3186221.html
最近由于项目需要，采用Qt开发的程序要能够支持双屏显示，在网上调研了以下，发现网页http://www.ics.com/blog/whats-new-qt-5-qscreen-class#.Ud9mY4csnXB中对于Qt的多屏幕管理有一定论述，指出采用QScreen可以获取窗口的相关信息，代码如下：
#include <QGuiApplication>
#include <QScreen>
#include <QDebug>
/*
Example of using Qt 5 QScreen class.
*/
// Helper function to return display orientation as a string.
QString Orientation(Qt::ScreenOrientation orientation)
{
switch (orientation) {
case Qt::PrimaryOrientation : return "Primary";
case Qt::LandscapeOrientation : return "Landscape";
case Qt::PortraitOrientation : return "Portrait";
case Qt::InvertedLandscapeOrientation : return "Inverted landscape";
case Qt::InvertedPortraitOrientation : return "Inverted portrait";
default : return "Unknown";
}
}
int main(int argc, char *argv)
{
QGuiApplication a(argc, &argv);
qDebug() << "Number of screens:" << QGuiApplication::screens().size();
qDebug() << "Primary screen:" << QGuiApplication::primaryScreen()->name();
foreach (QScreen *screen, QGuiApplication::screens()) {
qDebug() << "Information for screen:" << screen->name();
qDebug() << " Available geometry:" << screen->availableGeometry().x() << screen->availableGeometry().y() << screen->availableGeometry().width() << "x" << screen->availableGeometry().height();
qDebug() << " Available size:" << screen->availableSize().width() << "x" << screen->availableSize().height();
qDebug() << " Available virtual geometry:" << screen->availableVirtualGeometry().x() << screen->availableVirtualGeometry().y() << screen->availableVirtualGeometry().width() << "x" << screen->availableVirtualGeometry().height();
qDebug() << " Available virtual size:" << screen->availableVirtualSize().width() << "x" << screen->availableVirtualSize().height();
qDebug() << " Depth:" << screen->depth() << "bits";
qDebug() << " Geometry:" << screen->geometry().x() << screen->geometry().y() << screen->geometry().width() << "x" << screen->geometry().height();
qDebug() << " Logical DPI:" << screen->logicalDotsPerInch();
qDebug() << " Logical DPI X:" << screen->logicalDotsPerInchX();
qDebug() << " Logical DPI Y:" << screen->logicalDotsPerInchY();
qDebug() << " Orientation:" << Orientation(screen->orientation());
qDebug() << " Physical DPI:" << screen->physicalDotsPerInch();
qDebug() << " Physical DPI X:" << screen->physicalDotsPerInchX();
qDebug() << " Physical DPI Y:" << screen->physicalDotsPerInchY();
qDebug() << " Physical size:" << screen->physicalSize().width() << "x" << screen->physicalSize().height() << "mm";
qDebug() << " Primary orientation:" << Orientation(screen->primaryOrientation());
qDebug() << " Refresh rate:" << screen->refreshRate() << "Hz";
qDebug() << " Size:" << screen->size().width() << "x" << screen->size().height();
qDebug() << " Virtual geometry:" << screen->virtualGeometry().x() << screen->virtualGeometry().y() << screen->virtualGeometry().width() << "x" << screen->virtualGeometry().height();
qDebug() << " Virtual size:" << screen->virtualSize().width() << "x" << screen->virtualSize().height();
}
}于是，有了建立基于Qt的双屏显示程序的思路：建立两个QMainWindow，然后分别通过函数setGeometry分别指定两个QMainWindow为显示器一和显示器二的位置，这样总体的效果就是这个程序能够实现双屏的功能。同时需要注意，在定义QMainWindow的对象时，需要使用堆内存的方法，不能采用栈内存，在网页http://www.qtcentre.org/archive/index.php/t-16439.html中对此有过论述。