Are you sure the function is getting called (via a break point)?
-----Original Message----- From: Interest [mailto:interest-boun...@qt-project.org] On Behalf Of Jonathan Purol Sent: Friday, February 7, 2020 2:44 PM To: Qt Project <interest@qt-project.org> Subject: [Interest] Signal/Slot connection fails, even though QMetaObject::activate is called Hello everyone, I have a QMainWindow subclass called `text_editor` with a function `save` which looks as follows: ```cpp void text_editor::save() { _textbox->document()->setModified(false); _textbox->setFocus(); emit saved(); } ``` I now connect to that slot in another class like this: ```cpp _information_editor = new text_editor{this}; connect( _information_editor, &text_editor::saved, this, [=]() { std::cout << "hello\n"; } ); ``` I have verified that the signal is emitted, in fact, the method generated by the moc: ```cpp // SIGNAL 0 void text_editor::saved() { QMetaObject::activate(this, &staticMetaObject, 0, nullptr); } ``` is definitely called (verified with gdb and some other debugging shenenigans). In addition, the connection object returned by `connect` is valid, as verified by its implicit bool-cast operator. However, "hello" is never printed. I suspected this could be because `text_editor` inherits from `QMainWindow` and could have a different thread affinity, so I tried the following things: 1. Move the editor to the same thread as the object which establishes the connection 2. Use a QueuedConnection 3. Connect to the slot from WITHIN the text editor itself, making sure that we are 100% on the same slot and none of them worked. Just for clarification, the print of "hello" is only an example, so even if there was some issue with that, I would have detected it, the actual code is of course different. I'm really out of luck here, and would appreciate any help. Sincerely, Folling _______________________________________________ Interest mailing list Interest@qt-project.org https://lists.qt-project.org/listinfo/interest _______________________________________________ Interest mailing list Interest@qt-project.org https://lists.qt-project.org/listinfo/interest
