Developer Guide Widgets
The most of non skin-able GUI is created by using Qt-Widgets and the QtDesigner wysiwyg editor.
The UI files are used to autogenerated the c++ code that initializes the GUI. In Mixxx we use the dlg*.cpp files to receive events from these GUI elements.
The dlghidden.ui for instance builds the bar on top of the table with the hidden files in the library region. The class using the generated widgets is dlghidden.cpp
New UI files need to be introduced to scons via the depends.py file.
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