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/*!
\page portingcppapp.html
\title Porting C++ Applications to Qt 5
\brief Provides instructions to migrate a Qt 4 C++ application to Qt 5.

This topic talks about the Qt Widgets and Qt WebKit changes in Qt 5. The
following step-by-step instructions take you through the changes required to
port the \l{Animated Tiles Example}{Animated Tiles} application to Qt 5:

\list 1
   \li Open the Animated Tiles project using Qt Creator.
   \li Edit \c {main.cpp} and replace the \c {#include <QtGui>} instance with
       \c {#include <QtWidgets>}.
       The Perl-script \c fixqt4headers.pl can be used to scan the source files
       of a project and perform the replacements.
   \li Edit the \c {animatedtiles.pro} and add \c {QT += widgets} towards the
       end of the file.
       \note \l{Qt GUI} is included by default in all Qt applications unless excluded using the \c {QT -= gui} directive in the \c{qmake} project file.
   \li Save the changes and run the application.
\endlist

Once you see the application running, check whether it behaves as expected.

\image animatedtiles_snapshot.png "A snapshot of the \c animatedtiles application running on Ubuntu v12.04"

A similar change is needed to port Qt 4 C++ applications using Qt WebKit. The following
step-by-step instructions take you through the changes required to achieve this:

\list 1
   \li Open your project using Qt Creator.
   \li Replace all \c {#include <QtWebKit>} instances with
       \c {#include <QtWebKitWidgets>} in your project source.
   \li Edit the \c{.pro} file and add \c {QT += webkitwidgets}.

       \note If the \c {QT +=} statement already exists, append \c webkitwidgets
       to it.
   \li Save changes and run your application.
\endlist

For larger projects, we recommend initially enabling deprecated API by adding the define
\code
DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0
\endcode
to the \c{.pro} file. In a second step, the define can be removed.

It is possible to keep the project compiling with Qt 4 and Qt 5. This requires:

\list 1
   \li Omitting the module name from all includes. This is done by passing
       the command line option \c --strip-modules to \c fixqt4headers.pl.
   \li Adding scopes depending on the version of Qt to the \c{.pro} files:
       \code
       greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
       \endcode
   \li Introducing \c #if scopes around code using modified API:
       \code
       #if QT_VERSION >= 0x050000
           headerView->setSectionResizeMode(QHeaderView::ResizeToContents);
       #else
           headerView->setResizeMode(QHeaderView::ResizeToContents);
       #endif
       \endcode
\endlist

\section1 Related Topics
\list
\li \l {C++ API Changes}
\li \l {Porting QML Applications to Qt 5 Example}
\li \l {Qt Examples And Tutorials}
\endlist
*/
