Coverage for C:\Program Files\QGIS 3.10\apps\qgis-ltr\python\qgis\core\additions\fromfunction.py: 71%

1# -*- coding: utf-8 -*- 

2 

3""" 

4*************************************************************************** 

5 fromfunction.py 

6 --------------------- 

7 Date : May 2018 

8 Copyright : (C) 2018 by Denis Rouzaud 

9 Email : denis@opengis.ch 

10*************************************************************************** 

11* * 

12* This program is free software; you can redistribute it and/or modify * 

13* it under the terms of the GNU General Public License as published by * 

14* the Free Software Foundation; either version 2 of the License, or * 

15* (at your option) any later version. * 

16* * 

17*************************************************************************** 

18""" 

19 

20from .qgstaskwrapper import QgsTaskWrapper 

21from qgis._core import QgsTask 

22 

23 

24@staticmethod 

25def fromFunction(description, function, *args, on_finished=None, flags=QgsTask.AllFlags, **kwargs): 

26 """ 

27 Creates a new QgsTask task from a python function. 

28 

29 Example: 

30 

31 def calculate(task): 

32 # pretend this is some complex maths and stuff we want 

33 # to run in the background 

34 return 5*6 

35 

36 def calculation_finished(exception, value=None): 

37 if not exception: 

38 iface.messageBar().pushMessage( 

39 'the magic number is {}'.format(value)) 

40 else: 

41 iface.messageBar().pushMessage( 

42 str(exception)) 

43 

44 task = QgsTask.fromFunction('my task', calculate, 

45 on_finished=calculation_finished) 

46 QgsApplication.taskManager().addTask(task) 

47 

48 """ 

49 

50 assert function 

51 return QgsTaskWrapper(description, flags, function, on_finished, *args, **kwargs)