General and Desktop

@CKurdu Thx for reply. I am doing similar usually. I've been seeking something that in-box from pure QT without additional storing info about what in stack. Looks like nothing in it yet. First time I've been questioning about it about 4-5 years ago ...

No, signals are different. They are QObject derived class members and are generated with moc (the meta-object compiler). A signal is kinda what its name implies - it signals a change in some object and making a connection to it subscribes you to notifications about changes in that object. If there's no object there's nothing to signal a change in. It's kinda like subscribing to notifications from some website - if there's no website who would you get notifications from?

@dheerendra god bless you my friend you just saved our school projet.

Ok I think the issue is solved. Again something learned. void Game::makeNewMinefield() { auto newMinefield = new Minefield{ mDefaultFieldWidth, mDefaultFieldHeight, mDefaultMines }; auto returnItem = mBottomFrame->layout()->replaceWidget( mMinefield, newMinefield); if(!returnItem) { QMessageBox::critical(this, tr("Internal Error"), tr("Minefield could not be replaced"), QMessageBox::Close); qApp->quit(); } delete returnItem; mMinefield = newMinefield; }

There seems to be some caching issues. Don't worry it will appear as solved :-)

I could solve the issue with the example code. I had to add a member which remembers the last cell in the event filer. Than i could solve my Issue like this: if(event->type() == QEvent::MouseMove) { auto mouse_event = static_cast<QMouseEvent*>(event); QRect rect{cell->mapToGlobal(QPoint(0, 0)), cell->size()}; if(mouse_event->buttons().testFlag(Qt::LeftButton) && mouse_event->buttons().testFlag(Qt::RightButton)) { auto widget = qApp->widgetAt(mouse_event->globalPos()); if(widget) { auto currentCell = qobject_cast<Cell *>(widget); if(!currentCell) { if(mLastCell) { mLastCell->handleMouseMoveEventOutside(mouse_event); } mLastCell = nullptr; return true; } if(currentCell != mLastCell) { if(mLastCell) { mLastCell->handleMouseMoveEventOutside(mouse_event); } currentCell->handleMouseMoveEventInside(mouse_event); mLastCell = currentCell; } } return true; } }

Then please mark the topic as solved, thx :)

@Mr-Pang You can install it with the online installer together with a recent Qt version. That's how I do it on Ubuntu 18.04 ;)

@mrjj Thank you very much. I've tried to solve this problem for hours, but the solution was so easy.

Another way is to add make install as a custom build step in Qt Creator: https://doc.qt.io/qtcreator/creator-build-settings.html

So it looks like you are trying to push everything possible all the time. You should rather optimise your data processing so your GUI updates "make sense". There's no use trying to do updates at 1000Hz while the computer can at best be at about 100

I thought it might be fun to make a console based blue tooth sniffer using Qt. I may have to play with that for fun.

@pjorgegerman Hi https://doc.qt.io/archives/qt-5.5/build-sources.html#openssl-v1later "From Qt version 5.2 onwards, the officially supported version for OpenSSL is 1.0.0 or later. Versions >= 0.9.7 and < 1.0.0 might work, but are not guaranteed to." So OpenSSL v1.0.2L should work. If you have issues with compiling it, search the forum. other have done it before. https://forum.qt.io/topic/94328/qt-static-with-openssl-issue Yes building a static version takes lots of effort. Depending on your SQL needs later, it might also be a small fight if its not SQLLite you want to use. Its best to start clean over every time as keeping old build artifacts, more often cause issues than speed up the process. This one QtXlsx ? https://github.com/dbzhang800/QtXlsxWriter If yes, then i would go with option 2 Usage(2): Use source code directly and compiled it into the app to avoid having to build the module as static.

@sierdzio Thanks a lot for the clarification

@JonB thank you! Now I got it!

Sorry, I know it's like over a year later, but I have finally marked it as solved. Thanks for the help.

@jsulm sorry,but I want to know what exactly that x11.. because i understood x11 is for windowing system..(shall i ask more about x11 which you talking) but i am using the operating system: debian(linux) beagleboneboard Qtcreator(building to support beagleboneboard)...