仅在 PyCharm 的编辑器中缺少 qgis.core 模块中的类

Question

I would like to use PyCharm Community Edition 2020.1.2 x64 on Windows 10 as IDE for writing QGIS plugins. I need to base on old version - QGIS 2.18, so I need python 2.7, qt4, and also core modules from QGIS 2.18. I downloaded QGIS 2.18 from official site. It provides a ready to use python environment as.bat script, that sets all needed python paths. So I used path D:\Program Files\QGIS 2.18\bin\python-qgis-ltr.bat to set main python interpreter for my project.

After that I was able to run python console in PyCharm, import all QGIS modules, and any classes from QGIS standard collection like QgsFeature, QgsVectorLayer etc. Everything was fine untill I tried to import this classes from PyCharm editor in.py file as from qgis.core import QgsFeature . In editor PyCharm sees the package qgis.core and I'm able to import it, but PyCharm's code completion inside the module sees only classes that are saved in D:\Program Files\QGIS 2.18\apps\qgis-ltr\python\qgis\core\__init__.py eg QgsEditError class, but all standard QGIS class underlines on red.

Python console ran on exactly the same interpreter see the same sources as are visible in "External Libraries" tab in PyCharm, so command:

• qgis.core.__path__ returns ['D:\\Program Files\\QGIS 2.18\\apps\\qgis-ltr\\python\\qgis\\core'] ,
• qgis.core.__file__ returns 'D:\\Program Files\\QGIS 2.18\\apps\\qgis-ltr\\python\\qgis\\core\\__init__.pyc ,
• dir(qgis.core) returns full list of QGIS standard core classes.

If I run the.py script, in which PyCharm's code validator is showing incorrect import object by red underline, the script is executed without any error and I can easly print the imported QgsFeature object. Why my PyCharm's editor see different content of qgis.core module then console ran also from IDE on exactly the same interpreter?

Answer 1

Allow me to qualify myself. I lost interest for adventures and trail blazing in computing some time ago. I won some big battles and lost some too. And I unnecessary wasted a lot of time that could have been better spent. Nowadays, I just wait a reasonable period of time before upgrading anything, and wait a spell before downloading the newest anything, and pretty much avoid trying to do things outside a conventional path.

So your post got me curious and I looked around some. I found very little information about PyCharm being used building QGIS plugins. That pretty much tells me all I want to know: that it's not real common for PyCharm to be used in building QGIS plugins.

But there was quite abit of information about building QGIS plugins with python. There's even a QGIS Tutorial & Tips on the subject. QGIS suggests using the Qt Creator and further goes on to say that QGIS itself is written using the QT framework. "For plugin development, we use an application called Qt Creator."

If you overcome your current predicament I'd like to hear how you accomplished it.

For what it's worth, here's the link to the QGIS Tutorials & Tips.

https://www.qgistutorials.com/en/docs/building_a_python_plugin.html

Answer 2

Finally, the problem solved itself. It was something wrong with building a binary skeletons of C++ libraries, what PyCharm does every time the application is launched. My PyCharm didn't want to do it and I found many similar problems with other libraries (eg Qt) that people were struggling with. After two days my PyCharm just fixed itself and created all needed binary skeletons for my QGIS libraries.