Hfrhyu

I want to force closing Qgis project (QgsTask) in some point

NOTE:

QgsProject.instance().clear() # NOT WORKING

QgsTaskManager().cancelAll() # NOT WORKING

QgsTask.cancel() # NOT WORKING

task.canCancel() # FALSE

project = QgsProject.instance()
project.clear() # NOT WORKING
QgsTaskManager().cancelAll() # NOT WORKING
tasks = QgsApplication.taskManager().activeTasks()
for task in tasks:
 print (task.canCancel()) # False
 print (task.description()) # Loading “C:/Users/User/Desktop/some_project.qgs”
 print (task.flags()) # <qgis._core.QgsTask.Flags object at 0x000002330527E4C8>

 task.cancel() # NOT WORKING

Is there any way to force closing project or task or change flag QgsTask.CanCancel to True ?

I add an example of a task to load a project, For cancel only uncomment

task.cancel()

Sample

def completed(exception, result=None):
 if exception is None:
 if result is None:
 print('Completed with no exception and no result probably manually canceled by the user')
 else:
 print("completed " , result['task'])
 # But layers not show on canvas and refresh not work
 # Trick (probably don't know the right method)
 root = QgsProject.instance().layerTreeRoot()
 layers = QgsProject.instance().mapLayers()
 map_canvas_layer_list = [l for l in layers.values()]
 for layer in map_canvas_layer_list:
 node=root.findLayer( layer.id())
 v=node.isVisible ()
 node.setItemVisibilityChecked(not v)
 node.setItemVisibilityChecked(v)
 break
 else:
 print ("Failed Task")
 raise exception

def LoadProject(task,mFile):
 project = QgsProject.instance()
 project.read(mFile)
 return 'task': task.description()

mFile = r'D:sample.qgs'
task = QgsTask.fromFunction("Loading project",LoadProject,mFile=mFile,on_finished=completed, flags=QgsTask.CanCancel)

QgsApplication.taskManager().addTask(task)

# task.cancel() # For cancel , uncomment if you want cancel it
while QgsApplication.taskManager().countActiveTasks() > 0:
 QCoreApplication.processEvents()

Note: I suppose there is a method to make them visible, but I thought of that as a trick

tested QGIS 3.6.1

I hope it helps you