Question

I have a console application that uses QtCore and QtGui. I do not use the Qt event loop or create any instances of QApplication; I’m just using Qt’s string, list, and image manipulation functionalities. How do I get the imageformats plugins to load?

This app is on OS X and does not use an application bundle.

I was under the impression that placing the plugin files ./plugins/<pluginfolder>/*.dylib, where . is the directory of the application executable, would do the trick, as according to the deployment documentation “plugins” is the default search directory for plugins relative to the application bundle.

However, the plugins aren’t loading as I’m getting ‘invalid image format’ in my image processing functions. The same functions work on my development machine with the Qt binary package installed.

Answer 1

Just two ideas:
Try to search for strings (e.g. “/plugins”) in your Qt-dll using strings | grep or VI. May be that way you’ll find out the plugin directory.
As I’ve found out, on Windows the plugin-pathes are stored in the DLL as complete pathes during the installation.

Create an instance of QCoreApplication. Maybe the plugin-loading is triggered from there. Starting event loop shouldn’t be required.