Questions tagged as 'qt'

Tagged questions
2
answers

Qt handling of QFile files

I'm starting in QtCreator and I'm trying to manage files. I want to save a int in a file, and when I press a button it shows me that number in QSpinBox but I do not know how to return the type character int . My test code:...
asked by 11.06.2017 / 07:41
1
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Rotate QGraphicsItem - It does not over its center

I'm trying to rotate a QGraphicsItem on its own center, so it does not move its center, just turn X degrees ... I can not make it happen, it changes places, as if the whole scene were spinning but the rest of the Elements do not turn ... but he...
asked by 31.05.2018 / 16:39
1
answer

Send a QSerialPort variable to another file

I am currently programming an app in C ++ with IDE Qt but I need to send a QSerialPort variable to another .cpp file in order to have the connection in any screen of the application but it does not accept the variable and I would like to know if...
asked by 21.06.2017 / 00:52
1
answer

Read large text files quickly

I have a big problem reading / parsing large text files. The issue is the following are files that have many lines, about 150k lines and I have to read them and then parsed the information. I do it by means of a fread, reading ALL the file and t...
asked by 18.04.2017 / 15:13
1
answer

Convert a char into QString as it is done?

Hi I want to convert a char in QString for example I have this: QString s; char a = "cadena" I want to convert a in QString but I do not know how to do it.     
asked by 05.10.2016 / 23:45
1
answer

Qt cross-compile from Windows to Linux Embedded?

No matter how much I search and reread the documentation and wikis of Qt I do not understand how to compile for a target different from the host. I know that it is recommended to use Linux as a development environment but the goal is to be from...
asked by 07.10.2016 / 13:10
1
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Errors when using static libraries in QT

Hi, I'm a bit desperate with this if someone has worked with this ide that please specify why I can not create a static version? The errors are:    Makefile: 66: recipe for target 'sub-tools-make_first' failed   mingw32-make [1]: * [sub-tool...
asked by 25.08.2016 / 20:07
2
answers

Read Excel data with Qt Creator

I would like to know how I could read the data of an excel from a Qt application. I've tried it with the following code but it reads data without sense. #include <QFile> #include <QStreamText> int main(){ QFile archivo("datos....
asked by 06.11.2017 / 12:17
3
answers

Convert QString to char

How do you convert a QString to char ? some easy and understandable way? It's to understand better thanks.     
asked by 11.10.2016 / 23:05
1
answer

QPushButton does not appear

I'm doing a small form with Qt, I insert several QPushButton buttons, but I do not have to add the header that specifies it, nor do I add anything in the .cpp or the .h, but it works perfectly. Is the library included in another? In which?     
asked by 24.04.2018 / 22:01