Problem with QPixmap

[michaelboybo]

Hi

I'm trying to load an image into a QPixmap object, here is my code:


QPixmap blackKingPixmap;
std::cout << "Hello";
blackKingPixmap.load("images/black_king.png");
std::cout << "Hello";

When I run it, I only see one 'Hello' printed to the console, shortly after that the program terminates without printing the second 'Hello'.
I don't get any error messages when I run it, it simply just terminates. I have tried putting the 'images' folder in the 'resources' folder, and in the same folder as the .cpp file. I have tried taking the images out of the folder and putting them directly in the 'resources' folder. I have tried specifying the absolute path to the image ('C:<user>/ etcetc'). I even tried loading the image to a QImage first and then trying to create the QPixmap from the QImage. I have checked that the image definitely exists at the specified path, and that the permissions for accessing the image are correct. All of which to no avail! Basically I have tried everything that I (or ChatGPT) could think of to fix it, none of it worked.

Can someone please help me? (Or put me out of my misery haha)

Thanks a lot,
Michael

[zvoopz]

You need to set a container for your QPixmap. I do as follows and maybe you can try

ui->label_picRange->setVisible(true); //QLabel for image was defined in mainwindow.ui
picRange = QPixmap(":/img/picRange.jpg");  //QPixmap picRange was declared in the header
    if (picRange.isNull()) {
        qDebug() << "Failed to load picRange.jpg";
    } else {
//putting the image into the label
    ui->label_picRange->setPixmap(picRange.scaled(ui->label_picRange->width(), ui->label_picRange->height(), Qt::KeepAspectRatio));
    }

ui->label_picRange->setVisible(true); //QLabel for image was defined in mainwindow.ui
picRange = QPixmap(":/img/picRange.jpg");  //QPixmap picRange was declared in the header
    if (picRange.isNull()) {
        qDebug() << "Failed to load picRange.jpg";
    } else {
//putting the image into the label
    ui->label_picRange->setPixmap(picRange.scaled(ui->label_picRange->width(), ui->label_picRange->height(), Qt::KeepAspectRatio));
    }

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[Ginsengelf]

Hi, I think you should use a debugger to see what's going on there. Maybe check if the pixmap file itself is corrupted? Can you open it with other tools?

Ginsengelf

[KyleighCormier]

Always make sure to use the full path or double-check the path relative to the working directory. Use functions like QFileInfo::exists() to check the file before downloading.

[natalieportman]

Your program crashes because QPixmap requires a QApplication object to initialize the GUI system. Add `QApplication app(argc, argv);` at the start of your `main()` function to resolve this. Verify the image path is correct relative to the working directory, or test with an absolute path, and ensure the image format (e.g., PNG) is supported.

Slope Game

[edmiller]

It's likely due to a missing resource or an issue with the image file itself. Make sure the path to "images/black_king.png" is correct relative to your executable's working directory, and check if the image format is supported by Qt. You can add error handling by checking if blackKingPixmap.load() returns false, which will help identify if the loading failed. Additionally, consider using QImage for debugging, as it may provide more informative error messages.
slope game