Qt framework is a popular C++GUI framework developed by Nokia. And it is also cross platform compatible. Manydevelopers are using Qt to develop C++ GUI programs. In Qt, some importantcomponents are deserved our close attention. Many developers faced the problemwhen they put some widgets in a QScrollArea widget and they want it to displayscroll bars when the widgets inside the QScrollArea overflows. After manyexperiments, I propose a way which can show scroll bars as you expected. The relationship betweenwidgets and layout is the key here. Generally, we need not to add layout toscroll area dire...