[QGIS-Developer] PyQGIS 3.0: does not work under Windows (Anaconda package)

[Алексей Головизин]

Hi folks!

I've just tried to install QGIS 3.0 package in my Anaconda (Win7x64, 
Python 3.6 x64). I wanted to use QGIS widgets in my PyQt application. 
Alas, QGIS works incorrectly: at first, when I just tried to import qgis 
modules in Python, it said that it cannot find them. And when I manually 
set the PYTHONPATH, QGISPATH and PATH variables, it simply does not show 
my map (only the blank white screen).

Under Ubuntu 18.04 the script works correctly (there I just made 
`apt-get install python3-qgis`).

Can you tell me, how can I make it work under Windows too?

Here's my test script:

#!/usr/bin/env python3

import os

from PyQt5.QtWidgets import QWidget, QFrame, QHBoxLayout, QGridLayout

from qgis._core import QgsApplication, QgsRasterLayer
from qgis._gui import QgsMapCanvas


class TestWidget(QWidget):
     def __init__(self, parent=None):
         super(TestWidget, self).__init__(parent)
         self.main_layout = QHBoxLayout(self)
         self.canvas = QgsMapCanvas()
         self.main_layout.addWidget(self.canvas)

         base_layer_path = 
os.path.join(os.path.abspath(os.path.dirname(__file__)), "world.mbtiles")
         self.base_layer = QgsRasterLayer(base_layer_path, 'world')
         self.canvas.setLayers([self.base_layer])
         self.canvas.zoomToFullExtent()


if __name__ == '__main__':
     qgs = QgsApplication([], False)
     qgs.setPrefixPath(os.environ.get('QGISPATH', '/usr'), True)
     qgs.initQgis()

     w = TestWidget()
     w.show()

     qgs.exec_()
     qgs.exitQgis()


And here's my test map data (world.mbtiles): 
https://www.sendspace.com/filegroup/8OqffqxS3aWuRdwr4iolRQ


And here are my environment variables (set under Windows):


PYTHONPATH=C:/Anaconda3/Library/python
QGISPATH=C:/Anaconda3
PATH=C:/Anaconda3/share/qgis/python/qgis;C:/Anaconda3/Library/bin