A number of guides and documents are available that cover porting issues, from detailed coverage of API differences between Qt 3 and Qt 4 to platform and tool-specific documentation.
Porting advice for authors of new and existing Qt 3 applications. | |
Information about changes to the UI file format in Qt 4. | |
Hints and tips to assist with porting canvas applications to the Graphics View framework. | |
An overview of issues and techniques to consider when porting from Qt 3 to Qt 4. | |
An overview of the porting process for applications that use drag and drop. | |
An overview of changes to virtual functions in Qt 4. | |