Free Pascal Qt4 Binding


The Free Pascal Qt4 binding allows Free Pascal to interface with the C++ Library Qt.

This binding does not cover the whole Qt4 framework but only the classes needed by the Cross Platform Lazarus IDE to use Qt as a Widget set


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Version History

11 Dec 2013
Initial Qt5 Alpha release
29 Dec 2011
SSE Stack alignment fixes. Solves problems with Kde Oxygen Style Replaces V2.3
07 July 2011
More Range Check Error Fixes. Replaces V2.3
16 June 2011
Qt 4.7 support
03 Aug 2010
Qt for Maemo (N900)
19 Feb 2010
Added QScocketNotifier, QTcpServer, QUdpSocket, QPointF, QtVersion
18 Jan 2010
Qt qmake build system. qt4intf renamed to Qt4Pas


The following screenshots provide a glimpse of results achieved

Click on the thumnails for larger images.


Documentation about this Free Pascal Qt4 Binding can be found on this FPC Wiki Page


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V2.6Alpha (Qt 5.1.X)

Alpha release !

V2.5 (Qt 4.5.X, compatible till Qt 4.8.X)

V2.2 (Maemo 5 Qt 4.6.2 for N900 PR 1.2)

Maemo Binding Instructions

The Lazarus LCL/Qt code still needs a patch, coordination is in progress.

Lazarus LCL/Qt WebKit demo

This demo implements a very basic browser, and provides sample code for cookies, proxy, authentication, flash enabling ...

Needs Binding >= V1.72 (lazarus svn 21913)

Download LCL WebKit Demo