Task that is composed of sub-tasks to be executed in a serial way, which may be useful for example to add several layers in a single target dataset which does not support concurrent updates. More...
#include <qgstaskmanager.h>
Public Member Functions | |
| QgsTaskWithSerialSubTasks (const QString &desc=QString()) | |
| Constructor. | |
| ~QgsTaskWithSerialSubTasks () override | |
| void | addSubTask (QgsTask *subTask) |
| Add a subtask and transfer its ownership. | |
| void | cancel () override |
| Notifies the task that it should terminate. | |
 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. | |
Protected Member Functions | |
| bool | run () override |
| Performs the task's operation. | |
| 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. | |
Protected Attributes | |
| QList< QgsTask * > | mSubTasksSerial |
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... | |
| typedef QFlags< Flag > | Flags |
| 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. | |
Detailed Description
Task that is composed of sub-tasks to be executed in a serial way, which may be useful for example to add several layers in a single target dataset which does not support concurrent updates.
- Since
- QGIS 3.36
Definition at line 670 of file qgstaskmanager.h.
Constructor & Destructor Documentation
◆ QgsTaskWithSerialSubTasks()
|
inline |
Constructor.
Definition at line 676 of file qgstaskmanager.h.
◆ ~QgsTaskWithSerialSubTasks()
|
override |
Definition at line 939 of file qgstaskmanager.cpp.
Member Function Documentation
◆ addSubTask()
| void QgsTaskWithSerialSubTasks::addSubTask | ( | QgsTask * | subTask | ) |
Add a subtask and transfer its ownership.
The parent task must be added to a QgsTaskManager for subtasks to be utilized. Subtasks should not be added manually to a QgsTaskManager, rather, only the parent task should be added to the manager.
For now, subtasks can NOT be nested.
Definition at line 947 of file qgstaskmanager.cpp.
◆ cancel()
|
overridevirtual |
Notifies the task that it should terminate.
Calling this is not guaranteed to immediately end the task, rather it sets the isCanceled() flag which task subclasses can check and terminate their operations at an appropriate time. Any subtasks owned by this task will also be canceled. Derived classes must ensure that the base class implementation is called from any overridden version.
- See also
- isCanceled()
Reimplemented from QgsTask.
Definition at line 975 of file qgstaskmanager.cpp.
◆ run()
|
overrideprotectedvirtual |
Performs the task's operation.
This method will be called when the task commences (ie via calling start() ), and subclasses should implement the operation they wish to perform in the background within this method.
A task must return a boolean value to indicate whether the task was completed successfully or terminated before completion.
Implements QgsTask.
Definition at line 952 of file qgstaskmanager.cpp.
Member Data Documentation
◆ mSubTasksSerial
|
protected |
Definition at line 694 of file qgstaskmanager.h.
The documentation for this class was generated from the following files:
- /build/qgis-3.40.0+99sid/src/core/qgstaskmanager.h
- /build/qgis-3.40.0+99sid/src/core/qgstaskmanager.cpp
