Question

This question is from a past exam paper and it is used for revision purposes

#include <QApplication>
#include <QLabel>
#include <QVBoxLayout> 
#include <QTextEdit>
#include <QWidget> 

int main (int argc, char* argv[]) {
    QApplication app (argc, argv);
    QWidget window;

    QLabel* label =  new QLabel("Please enter some text");
    QTextEdit* textEdit = new QTextEdit;
    QVBoxLayout* layout = new QVBoxLayout;
    layout->addwidget(label);
    layout->addwidget(textEdit);

    window.setLayout(layout);
    window.show;

    return app.exec();
}

1. Qt provides a child management facility through the QObject class. Where is the QObject in the program above? Explain

2. The QObject class provides the function setParent(QObject *parent) to specify a Qbject to be its parent. Why is this function not use in this program?

3. The program uses both heap and stack objects. Explain how the parnt-child facility works when the:

a. parent is a heap obhect and the child objects are stack objects
b.parent is a stack obhect and the child objects are heap objects

Answer 1

QObject documentation is available here, and can also be accessed via Qt assistant. So go ahead and read it.