In the end I now found out that this is everthiny I need to do:
Qt Code:
  1. setupUi(this);
  2.  
  3. buttongroup = new QButtonGroup(this);
  4. buttongroup->addButton(radioButtonNoFFT);
  5. buttongroup->addButton(radioButtonFFT);
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finding this out however caused me about 2 hours of trying to find some code example and implement whatever I could find...