Initializes a virtual layer with postpone mode activated and reloads the data in a separated thread. More...

#include <qgsvirtuallayertask.h>

Inheritance diagram for QgsVirtualLayerTask:

Public Member Functions
	QgsVirtualLayerTask (const QgsVirtualLayerDefinition &definition)
	Constructor.

void	cancel () override
	Cancels the pending query and the parent task.

QgsVirtualLayerDefinition	definition () const
	Returns the virtual layer definition.

QString	exceptionText () const
	Returns the exception text or an empty string if no exceptions were raised.

QgsVectorLayer *	layer ()
	Returns the underlying virtual layer.

bool	run () override
	Reloads the data.

void	setExceptionText (const QString &exceptionText)
	Sets the exceptionText.

QgsVectorLayer *	takeLayer ()
	Returns the underlying virtual layer and ownership.

Public Member Functions inherited from QgsTask
	QgsTask (const QString &description=QString(), QgsTask::Flags flags=AllFlags)
	Constructor for QgsTask.

	~QgsTask () override

void	addSubTask (QgsTask *subTask, const QgsTaskList &dependencies=QgsTaskList(), SubTaskDependency subTaskDependency=SubTaskIndependent)
	Adds a subtask to this task.

bool	canCancel () const
	Returns `true` if the task can be canceled.

QList< QgsMapLayer * >	dependentLayers () const
	Returns the list of layers on which the task depends.

QString	description () const
	Returns the task's description.

qint64	elapsedTime () const
	Returns the elapsed time since the task commenced, in milliseconds.

Flags	flags () const
	Returns the flags associated with the task.

void	hold ()
	Places the task on hold.

bool	isActive () const
	Returns `true` if the task is active, ie it is not complete and has not been canceled.

double	progress () const
	Returns the task's progress (between 0.0 and 100.0)

void	setDependentLayers (const QList< QgsMapLayer * > &dependentLayers)
	Sets a list of layers on which the task depends.

void	setDescription (const QString &description)
	Sets the task's description.

TaskStatus	status () const
	Returns the current task status.

void	unhold ()
	Releases the task from being held.

bool	waitForFinished (int timeout=30000)
	Blocks the current thread until the task finishes or a maximum of timeout milliseconds.

Additional Inherited Members
Public Types inherited from QgsTask
enum	Flag { CanCancel = 1 << 1 , CancelWithoutPrompt = 1 << 2 , Hidden = 1 << 3 , Silent = 1 << 4 , AllFlags = CanCancel }
	Task flags. More...

enum	SubTaskDependency { SubTaskIndependent = 0 , ParentDependsOnSubTask }
	Controls how subtasks relate to their parent task. More...

enum	TaskStatus { Queued , OnHold , Running , Complete , Terminated }
	Status of tasks. More...

Signals inherited from QgsTask
void	begun ()
	Will be emitted by task to indicate its commencement.

void	progressChanged (double progress)
	Will be emitted by task when its progress changes.

void	statusChanged (int status)
	Will be emitted by task when its status changes.

void	taskCompleted ()
	Will be emitted by task to indicate its successful completion.

void	taskTerminated ()
	Will be emitted by task if it has terminated for any reason other then completion (e.g., when a task has been canceled or encountered an internal error).

Protected Slots inherited from QgsTask
void	setProgress (double progress)
	Sets the task's current progress.

Protected Member Functions inherited from QgsTask
virtual void	finished (bool result)
	If the task is managed by a QgsTaskManager, this will be called after the task has finished (whether through successful completion or via early termination).

bool	isCanceled () const
	Will return `true` if task should terminate ASAP.

Detailed Description

Initializes a virtual layer with postpone mode activated and reloads the data in a separated thread.

Since: QGIS 3.2

Definition at line 33 of file qgsvirtuallayertask.h.

Constructor & Destructor Documentation

◆ QgsVirtualLayerTask()

QgsVirtualLayerTask::QgsVirtualLayerTask ( const QgsVirtualLayerDefinition & definition )

Constructor.

Parameters

definition The definition to use for initializing the virtual layer

Definition at line 22 of file qgsvirtuallayertask.cpp.

Member Function Documentation

◆ cancel()

void QgsVirtualLayerTask::cancel ( )

overridevirtual

Cancels the pending query and the parent task.

Reimplemented from QgsTask.

Definition at line 62 of file qgsvirtuallayertask.cpp.

◆ definition()

QgsVirtualLayerDefinition QgsVirtualLayerTask::definition ( ) const

Returns the virtual layer definition.

Definition at line 47 of file qgsvirtuallayertask.cpp.

◆ exceptionText()

QString QgsVirtualLayerTask::exceptionText ( ) const

Returns the exception text or an empty string if no exceptions were raised.

Since: QGIS 3.4

Definition at line 68 of file qgsvirtuallayertask.cpp.

◆ layer()

QgsVectorLayer * QgsVirtualLayerTask::layer ( )

Returns the underlying virtual layer.

Definition at line 52 of file qgsvirtuallayertask.cpp.

◆ run()

bool QgsVirtualLayerTask::run ( )

overridevirtual

Reloads the data.

Returns: true if the virtual layer is valid, false otherwise.

Implements QgsTask.

Definition at line 30 of file qgsvirtuallayertask.cpp.

◆ setExceptionText()

void QgsVirtualLayerTask::setExceptionText ( const QString & exceptionText )

Sets the exceptionText.

Since: QGIS 3.4

Definition at line 73 of file qgsvirtuallayertask.cpp.

◆ takeLayer()

QgsVectorLayer * QgsVirtualLayerTask::takeLayer ( )

Returns the underlying virtual layer and ownership.

Definition at line 57 of file qgsvirtuallayertask.cpp.

The documentation for this class was generated from the following files:

/build/qgis-3.34.0+99sid/src/core/qgsvirtuallayertask.h
/build/qgis-3.34.0+99sid/src/core/qgsvirtuallayertask.cpp

Public Member Functions

Additional Inherited Members