How to fix "QApplication: No such file or directory" error?

Question

linux

When compiling a file in qmake, such an error takes off.

The code:

#include <QApplication>
#include <QTextEdit>

int main(int argv, char **args)
{
    QApplication app(argv, args);

    QTextEdit textEdit;
    textEdit.show();

    return app.exec();
}

Qmake installed via "sudo apt-get install qt5-qmake"
When compiling any Qt projects, errors come out:
QWidget - No such file or directory
QApplication - No such file or directory
and similar.
What to do?

Answer 1

On my machine, QApplication is in a QtWidgets subdirectory that you don't have in your path.