General and Desktop

For those who end up looking here : It seems that this is a Qt 5.6 bug, it works fine in Qt 5.14 Edit : The bug itself may be related to the use of QSurfaceFormat::setDefaultFormat after application startup : Qt 5.14 warned me about a piece of code I was not aware saying that it could cause context sharing issues. Having it removed seems to have solved the bug when i got back to Qt 5.6

I'm sorry to say it, but I'm leaning toward a questionable protocol on the embedded board. You are trying to parse block commands from a stream data feed. There are oh so many potential problems by not using either 1) all fixed length commands, or 2) choosing and consistently using an end of message indicator like \n...and consistently sending a status indicator upon receipt and processing of EVERY COMMAND.

Hi Any help with this would be unfathomably wonderful. I've been googling for hours, and my unfamiliarity with C++ . What i would do it to create a new empty UI form with .h and .cpp (and add it to the project) [image: WSJJRd.png] And then copy the UI file over the new empty one. (creator closed ) Open Creator Then clean all, rebuild all and it should generate the ui_xxx automatically and in your .cpp you have access to all via UI as normal in c++. QUiLoader also works great but no access via UI->

Hi Apply layouts using right-click on the widgets then layout menu. The red layouts are for inserting into "right click layouts" and wont work if used alone. That fooled me alot in the beginning as you insert all other elements using the Widget menu/list :=)

Hi Even if the other already explained it... Think of it as a role. The role of being an index type. We need sometimes to flag the index as invalid. And since none ever uses negative indexes, using signed can be used for that.

@jsulm I just tried to change the places of delete ui and delete colorBarWidget: ColorBarEditorForm::~ColorBarEditorForm() { delete colorBarWidget; delete ui; for (int i = 0; i < scene->items().size(); i++){ delete scene->items().at(i); } delete scene; } And now I dont see any error. Is it possible that when ui is closed a QwtScaleWidget (ColorBarWidget is inherited form QwtScaleWidget) destructor is called?

@Kishore-0 You could try offline installer for a Qt version which works on Ubuntu 14.04

It's QSqlQueryModel which has an internal pagination. Search the forum for QSqlQueryModel and you will find some threads about this.

What OS are you using? If you are working on windows i highly suggest getting a PEAK can adapter instead. On linux if you follow IXXAT's documentation for installing socketcan drivers then it will work easily with QCanBus.

@SGaist said in Porting an application on Ubuntu: Hi, How did you install Qt on both these machines ? I installed it on Ubuntu. The problem is on Ubuntu. I have Qt installed on another machine on Debian (for RPi) and on this installation the widget application runs without problems. I found the solution. During the installation I broke the GPU driver libraries, so this helped sudo apt install --reinstall mali-x11

@Simon-ZanG Documentation says: "The mouse cursor is generally not grabbed", so you're out of luck with Qt here. "are there any APIs to do that" - I think you will have to look into native APIs for that.

Can you share your test file? Perhaps you are using/ not using correct main-generating macro?

@delivite Make your slot public, not private

You should check if the sql driver supports this feature: https://doc.qt.io/qt-5/qsqldriver.html#DriverFeature-enum (hint: mysql does not support it - so it's not possible)

So did you actually implement this ctor and include the source of it in your project?

Try your original code with the address of 0.0.0.0 I believe you may need privilege to bind to a specific interface.