Having trouble with QGraphicsView

I am having trouble displaying an image (or anything) in a QGraphicsView

I have a frame named mainwindow which contains simply a QGraphicsView widget named mainGraphics

I have an image named imageMap.bmp which I have added to the resource file

When I run the program, the QGraphicsView mainGraphics is blank.... just a white space in the frame..... if I change the setSceneRect param, the scrollable area does change size, so I am def changing parameters on the correct item, but just none of the graphics will show up...???

The code in mainwindow.cpp is as follows:

Code:

---

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QtGui>
 
MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent), ui(new Ui::MainWindow)
{
    ui->setupUi(this);
 
    ui->mainGraphics->setSceneRect(0,0,500,500);
    QPixmap back(":/images/imageMap.bmp");
    ui->mainGraphics->setBackgroundBrush(back);
 
 
    QGraphicsScene scene;
    scene.addText("Some text");
    scene.addLine(10,10,200,200);
 
    ui->mainGraphics->setScene(&scene);
    ui->mainGraphics->show();
 
 
 
 
}
 
MainWindow::~MainWindow()
{
    delete ui;
}

---

a file named main.cpp contains the main() function which starts the program

may be the scene is obscuring the background image of the view ... make QGraphicsScene little transperent using setOpacity() ..

also use QGraphicsView::setCacheMode(CacheBackground);

I have set the cach mode to cachBackground but it still doesn't make any difference.... nothing is showing up....

Also, the QGraphicsScene does not have a setOpacity() function, that is only implemented by QGraphicsItem.....

I don't think it is an opacity issue as even the text and line is not showing up....

if not setOpacity() then alpha value u can set in QColor ()

ok did u see the padnavigator example ... they set pixmap for the graphicsView ... see where the problem arise ..

I really appreciate your help wagmare, but unfortunaltely I am still having problems...

I have had a look through the padnavigator example but I dont see where I have implemented it any different apart from the fact that they made a subclass of QGraphicsView...


Also... if I remove the QGraphicsScene element, it still does not show a background.... so its not an opacity problem