Usage

The tutorial shows how to use the widget.

Interface

This is the sample of the QSmartGraphicsView. The left view receives the image loaded from the system, and the right view receives the selected sub-image of the left view.

The left top corner of any view is the menu bar. The eye is normal view mode, and the arrow is the region selection mode.

The menu bar can be hidden by pressing the key 'H' on your keyboard,

or right click on the view to hide it.

In region selection mode, you have to press Ctrl to drag the image around. Feel free to select any region then right click

and press "Copy Selected Region" to get the sub-image.

Code

The following code reads the image from the system and puts into the qsmartgraphicsview

QStringList fileNames = QFileDialog::getOpenFileNames(this,tr("Open File"),0,"Image files (*.png *.bmp *.jpg);;PNG (*.png);;BMP (*.bmp);;JPG (*.jpg)");

if(fileNames.isEmpty())
    return;

int img_w = 0, img_h = 0;
std::vector<QImage> images;
for(int i = 0; i < fileNames.size(); i++)
{
    QImage tmp(fileNames.at(i));
    if(!tmp.isNull())
    {
        if(tmp.width() > img_w){img_w = tmp.width();}
        if(tmp.height() > img_h){img_h = tmp.height();}
        images.push_back(tmp);
    }
}

if(!images.empty())
{
    ui->graphicsView->initialize(images.size(), img_w, img_h);  //initial qgraphics view
    ui->graphicsView->setImagefromQImage(images);
}

qsmartgraphicsview must be initialize before use.

The "Copy Selected Region" function triggers a signal sendSelectedRegion(QImage) when clicked. You can connect it to a slot to receive the image.

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    connect(ui->graphicsView, SIGNAL(sendSelectedRegion(QImage)),this,SLOT(receiveSelectedRegion(QImage)));
}

void MainWindow::receiveSelectedRegion(const QImage &img)
{
    //Do something
}