[Qt-interest] Qt Plugins Windows

[David Ching]

"Dave Cawley" <sakrag at gmail.com> wrote in message 
news:hq9252$5d0$1 at eple.troll.no...
> Hi,
>
> I am writing a Qt application that takes advantage of the svg and sqlite 
> plugins.  Everything works great on linux, however on windows, the correct 
> plugins are never loaded so the svg icons are null and the database 
> connection fails.  I have tried following the deployment guide for 
> windows, I have copied the imageformats, iconengines, and sqldrivers 
> directories into my applications directory, checked the dependencies of 
> the dlls in a dependency viewer, tried placing the dlls in the same 
> directory as my application, and tried using 
> QApplication::addLibraryPath() to specify my own location for them all to 
> no avail.

For some reason I don't understand, Qt builds the plugin DLL's with a 
manifest requiring the C runtime DLL's.  This causes them to fail to be 
loaded as the runtime DLL's are not distributed in the plugin's folder.  So 
for all the plugins I use, I need to build them specially without the 
manifest, e.g. for QtAccessibleWidgets4.dll, here's what I do:

Edit C:\Qt\4.5.3-vc\src\plugins\accessible\widgets\widgets.pro so that it 
builds qtaccessiblewidgets4.dll without the manifest.  Add at the bottom:

    CONFIG -= embed_manifest_dll


Then rebuild the plugin.


-- David