Display a QMessageBox from a QThread
Emit a signal. Since you cannot do UI stuff in a Qthread
, instead send your message as an argument of your signal.
signal decalaration in your qthread:
signals: void write2SysStatus(QString theMessage);
emitting the signal from the qthread:
emit write2SysStatus("Some status");
slot declaration/definition in QMainWindow:
public slots: void eWriteLine ( QString theMessage ){ //this is where you use you message box. }
connecting of the slot and signal:
connect(pFPSengine, SIGNAL(write2SysStatus(QString)), this,SLOT(eWriteLine(QString)));
https://stackoverflow.com/questions/4299493/display-a-qmessagebox-from-a-qthread
You can't create widgets in any other thread than the main thread (the one from app.exec()) If you want to popup a message box based on something happening in a thread, you must emit a signal from that thread back to e.g. your main window and use your message box there
https://forum.qt.io/topic/32255/pop-up-a-qmessagebox-from-a-qthread