General and Desktop

@AshishDev said in Are Qt Open Source and Qt Commercial different.: They take the code from the open source branch and sell it with a commercial license. They don't "take code from the open source branch". They make the code available under multiple licenses (GPL or LGPL or Commercial). Users can choose which license they want to use. Different licenses come with different freedoms and obligations: If you choose the GPL license, then one of your obligations is to license your own software under the GPL. If you choose the commercial license, then one of your obligations is to pay the Qt Company. Is it not a violation of the GPL license? I don't see any violations here.

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@user4592357 said in remove timer single shot delay after a condition is met: so how can i make sure the child process does its initialisation inside the first slot, and not after it has finished You can't. You have no control over, or knowledge of, what the child is doing in the way of initialisation or otherwise. Quite apart from, you don't even know how the OS is scheduling time between your process and another process. i.e. only have singleShot delay if app was first time loaded, next times i don't wanna have delay To answer just that: just keep a bool variable to tell you whether it's first time or not, and don't do delay if you say you don't want it after first time.

Can you show how you do that ? Did you try starting your application with the QT_DEBUG_PLUGINS environment variable set to 1 ?

Very, very interesting. Never knew about that QMAKE_SUBSTITUTES. In my project file: GIT_VERSION = $$system(git --git-dir="C:/wifibutton"/.git --work-tree="C:/wifibutton" describe --always --tags) win32 { // this is to remove characters that could prevent compilation. GIT_VERSION ~= s/-\d+-g[a-f0-9]{6,} } QMAKE_SUBSTITUTES += config.h.in and config.h.in: #ifndef CONFIG_H_IN #define CONFIG_H_IN #define APP_VERSION '"$$GIT_VERSION"' #endif // CONFIG_H_IN and in my source code: QString version(APP_VERSION); // etc. Thanks!

@Helg1980 said in How do I delete the current QTreeWidget element correctly?: QCssParser::parseColorValue: Specified color without alpha value but alpha given: 'rgb 27, 29, 35, 0' You have a css somewhere which defines a wrong color rgb value.

@A-Newbie said in QFile, QThread, QConcurrent and how to Qt: Regardless, I got answers pretty much to all of my questions and everyone helped a lot. great 👍 Is there a way to simply have this topic as solved without picking a specific answer? sure bottem right side, topic tools button, simply set it to solved there

@mganesh Please read through https://doc.qt.io/qt-5/signalsandslots.html, looking at the examples. Please move away from SIGNAL/SLOT() macros, which are very old, and use the "new" syntax described there.

@Merlino Try to start it with strace: strace ./YOUR_APP You can post its output here. It can give some hints.

It looks like "model" is a C++ object, but I cannot trace where it is added or exposed to QML. If anyone can tell me how I can trace this ?

@Bonnie It was the reason. Thank you very much!

@Bonnie OK, thank you.

@jsulm Thank you! That makes a lot of sense. I will go with a SQLite database (or whatever is simplest).

@helloworldddd said in DHT11 Sensor with RPI: do u know how to use plot values to time, time as x axis on pyqtgraph? Sorry, I never used pyqtgraph. Did you check its documentation?

I have given up on that project for now. It has many many bugs :(

Okay so that got me going in the correct direction, My headers were actually okay, but I was not running the commands the right way. I was using a standard old cmd.exe, which appeared to have gcc.exe configured in the path, alone with g++.exe and mingw32-make.exe, except for some reason the "\bin" directory was not in the PATH variable somehow. I assumed that it was because it found gcc.exe, and I was wrong (still not sure how I was wrong with that logic). TL;DR there is a "mingw-w64.bat" in the PROGFIL~1 directory that you need to execute (which sets the PATH) and then run the configure.bat command inside that window that pops up.

Attached it to a QDialog and it worked. Woops.