(C++) QGraphicsProxyWidget

 

QGraphicsProxyWidget is the class that is returned when a QWidget is added to a QGraphicsScene. From that moment on, the QWidget can be modified in its original form, but also by its QGraphicsProxyWidget, the latter enabling for scaling and rotation.

 

• QGraphicsProxyWidget example 1: screenshot (png), displays a single QLineEdit
• QGraphicsProxyWidget example 2: screenshot (png), displays multiple QLineEdits
• QGraphicsProxyWidget example 3: screenshot (png), multiple movable widgets with a window frame
• QGraphicsProxyWidget example 4: screenshot (png), multiple unmovable widgets despite QGraphicsItem::ItemIsMovable flag
• QGraphicsProxyWidget example 5: screenshot (png), multiple movable widgets that cannot be focused on
• QGraphicsProxyWidget example 6: screenshot (png), multiple movable focusable widgets

 

 

 

 

 

Technical facts

 

Application type(s)

• Desktop application

Operating system(s) or programming environment(s)

• Lubuntu 12.10 (quantal)

IDE(s):

• Qt Creator 2.5.2

Project type:

• GUI application

C++ standard:

• C++98

Compiler(s):

• G++ 4.7.2

Libraries used:

• Qt: version 4.8.3 (32 bit)
• STL: GNU ISO C++ Library, version 4.7.2

 

 

 

 

 

Qt project file: CppQGraphicsProxyWidgetExample1.pro

 

---

QT       += core QT       += gui QMAKE_CXXFLAGS += -Wextra -Werror TARGET = CppQGraphicsProxyWidgetExample1 CONFIG   += console CONFIG   -= app_bundle TEMPLATE = app SOURCES += main.cpp

 

 

 

 

 

main.cpp

 

---

#include <QApplication> #include <QGraphicsProxyWidget> #include <QGraphicsScene> #include <QGraphicsView> #include <QLineEdit> int main(int argc, char **argv) {   //Create the application   QApplication app(argc, argv);   //Create the Qt Graphics Framework components   QGraphicsScene scene;   QGraphicsView view(&scene);   view.setGeometry(100,100,400,200);   view.show();   //Create a QWidget   QLineEdit *const edit = new QLineEdit;   //Add the QWidget and obtain its proxy   QGraphicsProxyWidget * const proxy = scene.addWidget(edit);   //Modify the widget by using its proxy   proxy->setScale(2.0);   proxy->setRotation(30);   return app.exec(); }