摘要： We can show a image with automatic scroll bars with the use of QScrollArea.This is a simple application with QScrollArea.#include <QtGui/QApplication>#include <QLabel>#include <QScrollArea>#include "qmlapplicationviewer.h"Q_DECL_EXPORT int main(int argc, char *argv[]){ QA 阅读全文

摘要： To paint on a device, usually a widget, we need to overload the function void QWidget::paintEvent(QPainteEvent *event){}We also need to construct the object of QPainter in the function of paintEvent like this: QPainter painter(this);Then we will be able to use QPainter whataver we like. 阅读全文

摘要： QWidget::width();QWidget::height(); 阅读全文