(C++) QtExample18

This Qt example shows how to stretchdraw and rotate an image, like this screenshot (png).

Download the Qt Project of 'QtExample18' (zip)

Technical facts

Application type(s)

Desktop application

Operating system(s) or programming environment(s)

Lubuntu 15.04 (vivid)

Qt Creator 3.1.1

GUI application

C++11

G++ 4.9.2

Libraries used:

Qt: version 5.4.1 (32 bit)
STL: GNU ISO C++ Library, version 4.9.2

Qt project file: ./CppQtExample18/CppQtExample18.pro

exists(../../DesktopApplication.pri) { include(../../DesktopApplication.pri) } !exists(../../DesktopApplication.pri) { QT += core gui greaterThan(QT_MAJOR_VERSION, 4): QT += widgets TEMPLATE = app CONFIG(debug, debug|release) { message(Debug mode) } CONFIG(release, debug|release) { message(Release mode) DEFINES += NDEBUG NTRACE_BILDERBIKKEL } QMAKE_CXXFLAGS += -std=c++11 -Wall -Wextra unix { QMAKE_CXXFLAGS += -Werror } } exists(../../Libraries/Boost.pri) { include(../../Libraries/Boost.pri) } !exists(../../Libraries/Boost.pri) { win32 { INCLUDEPATH += \ ../../../Projects/Libraries/boost_1_55_0 } } SOURCES += main.cpp SOURCES += dialog.cpp HEADERS += dialog.h FORMS += dialog.ui RESOURCES += resources.qrc

./CppQtExample18/dialog.h

#ifndef DIALOG_H #define DIALOG_H #pragma GCC diagnostic push #pragma GCC diagnostic ignored "-Weffc++" #pragma GCC diagnostic ignored "-Wunused-local-typedefs" #include <boost/shared_ptr.hpp> #include <QDialog> #pragma GCC diagnostic pop struct QGraphicsPixmapItem; struct QGraphicsScene; namespace Ui { class Dialog; } class Dialog : public QDialog { Q_OBJECT public: explicit Dialog(QWidget parent = 0); Dialog(const Dialog&) = delete; Dialog& operator=(const Dialog&) = delete; ~Dialog(); private: Ui::Dialog ui; boost::shared_ptr<QGraphicsScene> m_scene; boost::shared_ptr<QGraphicsPixmapItem> m_background; }; #endif // DIALOG_H

./CppQtExample18/dialog.cpp

#include "dialog.h" #pragma GCC diagnostic push #pragma GCC diagnostic ignored "-Weffc++" #pragma GCC diagnostic ignored "-Wunused-local-typedefs" #include "ui_dialog.h" #include <QGraphicsPixmapItem> #include <QGraphicsScene> #pragma GCC diagnostic pop Dialog::Dialog(QWidget *parent) : QDialog(parent), ui(new Ui::Dialog), m_scene(new QGraphicsScene), m_background(new QGraphicsPixmapItem) { ui->setupUi(this); ui->graphicsView->setScene(m_scene.get()); m_scene->addItem(m_background.get()); m_background->setPixmap(QPixmap(":/images/R.bmp")); //Draw image 20x as large m_background->setScale(20.0); //Rotate image by 30 degree m_background->setRotation(30.0); } Dialog::~Dialog() { delete ui; }

./CppQtExample18/main.cpp

`#pragma GCC diagnostic push #pragma GCC diagnostic ignored "-Weffc++" #pragma GCC diagnostic ignored "-Wunused-local-typedefs" #include <QApplication> #include "dialog.h" #pragma GCC diagnostic pop int main(int argc, char *argv[]) { QApplication a(argc, argv); Dialog w; w.show(); return a.exec(); }`