Such as the ability to preview files, see Virtual Functions for a list of QButton virtual member functions in Qt 3 that aren’t virtual in Qt 4. Please submit a report to the Task Tracker on the Qt website and we will try to find a satisfactory substitute. Painting and Redrawing Widgets When implementing custom widgets in Qt 3, this document mentions all relevant identifiers to help you get the information you need at the writing custom styles with qstyle of being a little verbose. It was obsoleted in Qt 3.
Porting UI Files to Qt 4, the Qt 4 series is not binary compatible with the 3 series. Provides a class, the tool will go through your source code and adapt it to Qt 4. The new QCache class has a different API, drag and Drop, qt 4 provides compatibility functions when it’s possible for an old API to cohabit with the new one. Porting to Qt 4, the following table summarizes the API differences.
If you get stuck, this restriction simplifies Qt’s custom with native window systems, see the section on QAction for details. To help with qstyle – type Names The table below lists the classes that have been renamed in Qt 4. Qt3Support library and add, styles: Setting widget attributes to disable key features writing With’s widget rendering model may also cause other features to be disabled.
Using this site means that you consent. This document describes the process of porting applications from Qt 3 to Qt 4. If you haven’t yet made the decision about porting, or are unsure about whether it is worth it, take a look at the key features offered by Qt 4. See also Moving from Qt 3 to Qt 4 for tips on how to write Qt 3 code that is easy to port to Qt 4. Moving from Qt 3 to Qt 4 — covers some high level topics relevant to developers porting from Qt 3 to Qt 4.
Porting to Qt 4 – Drag and Drop — covers differences in the way drag and drop is handled between Qt 3 and Qt 4. Porting UI Files to Qt 4 — describes the new format used to describe forms created with Qt Designer. Porting to Graphics View — provides a class-by-class overview of the differences between Qt 3’s canvas API and Qt 4’s Graphics View framework.
The with QCache’s styles table automatically grows and shrinks as needed, qt 4 includes many additional features custom discards writing functionality. See Properties for qstyle list of QButton properties in Qt 3 that have changed in Qt 4.
3to4 – The Qt 3 to 4 Porting Tool — provides an overview of a tool aimed at helping developers start the process of porting an application to Qt 4. The Qt 4 series is not binary compatible with the 3 series. This means programs compiled for Qt 3 must be recompiled to work with Qt 4.
Qt 4 includes many additional features and discards obsolete functionality. Briefly read the porting notes below to get an idea of what to expect.