Handles HTTP network content fetching in a background task. More...
#include <qgsnetworkcontentfetchertask.h>
Signals | |
| void | fetched () |
| Emitted when the network content has been fetched, regardless of whether the fetch was successful or not. More... | |
 Signals inherited from QgsTask | |
| void | begun () |
| Will be emitted by task to indicate its commencement. More... | |
| void | progressChanged (double progress) |
| Will be emitted by task when its progress changes. More... | |
| void | statusChanged (int status) |
| Will be emitted by task when its status changes. More... | |
| void | taskCompleted () |
| Will be emitted by task to indicate its successful completion. More... | |
| 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). More... | |
Public Member Functions | |
| QgsNetworkContentFetcherTask (const QUrl &url) | |
| Constructor for a QgsNetworkContentFetcherTask which fetches the specified url. More... | |
| QgsNetworkContentFetcherTask (const QNetworkRequest &request) | |
| Constructor for a QgsNetworkContentFetcherTask which fetches the specified network request. More... | |
| ~QgsNetworkContentFetcherTask () override | |
| void | cancel () override |
| Notifies the task that it should terminate. More... | |
| QNetworkReply * | reply () |
| Returns the network reply. More... | |
| bool | run () override |
| Performs the task's operation. More... | |
| Public Member Functions inherited from QgsTask | |
| QgsTask (const QString &description=QString(), QgsTask::Flags flags=AllFlags) | |
| Constructor for QgsTask. More... | |
| ~QgsTask () override | |
| void | addSubTask (QgsTask *subTask, const QgsTaskList &dependencies=QgsTaskList(), SubTaskDependency subTaskDependency=SubTaskIndependent) |
| Adds a subtask to this task. More... | |
| bool | canCancel () const |
Returns true if the task can be canceled. More... | |
| QList< QgsMapLayer *> | dependentLayers () const |
| Returns the list of layers on which the task depends. More... | |
| QString | description () const |
| Returns the task's description. More... | |
| qint64 | elapsedTime () const |
| Returns the elapsed time since the task commenced, in milliseconds. More... | |
| Flags | flags () const |
| Returns the flags associated with the task. More... | |
| void | hold () |
| Places the task on hold. More... | |
| bool | isActive () const |
Returns true if the task is active, ie it is not complete and has not been canceled. More... | |
| double | progress () const |
| Returns the task's progress (between 0.0 and 100.0) More... | |
| void | setDependentLayers (const QList< QgsMapLayer *> &dependentLayers) |
| Sets a list of layers on which the task depends. More... | |
| TaskStatus | status () const |
| Returns the current task status. More... | |
| void | unhold () |
| Releases the task from being held. More... | |
| bool | waitForFinished (int timeout=30000) |
| Blocks the current thread until the task finishes or a maximum of timeout milliseconds. More... | |
Additional Inherited Members | |
| Public Types inherited from QgsTask | |
| enum | Flag { CanCancel = 1 << 1, 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... | |
| Protected Slots inherited from QgsTask | |
| void | setProgress (double progress) |
| Sets the task's current progress. More... | |
| 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). More... | |
| bool | isCanceled () const |
Will return true if task should terminate ASAP. More... | |
Detailed Description
Handles HTTP network content fetching in a background task.
Provides a simple method for fetching remote HTTP content in a QgsTask. Url redirects are automatically handled.
After constructing a QgsNetworkContentFetcherTask, callers should connect to the QgsNetworkContentFetcherTask::fetched signal. They can then safely access the network reply() from the connected slot without danger of the task being first removed by the QgsTaskManager.
- See also
- QgsNetworkContentFetcher
- Since
- QGIS 3.2
Definition at line 47 of file qgsnetworkcontentfetchertask.h.
Constructor & Destructor Documentation
◆ QgsNetworkContentFetcherTask() [1/2]
| QgsNetworkContentFetcherTask::QgsNetworkContentFetcherTask | ( | const QUrl & | url | ) |
Constructor for a QgsNetworkContentFetcherTask which fetches the specified url.
Definition at line 22 of file qgsnetworkcontentfetchertask.cpp.
◆ QgsNetworkContentFetcherTask() [2/2]
| QgsNetworkContentFetcherTask::QgsNetworkContentFetcherTask | ( | const QNetworkRequest & | request | ) |
Constructor for a QgsNetworkContentFetcherTask which fetches the specified network request.
Definition at line 27 of file qgsnetworkcontentfetchertask.cpp.
◆ ~QgsNetworkContentFetcherTask()
|
override |
Definition at line 33 of file qgsnetworkcontentfetchertask.cpp.
Member Function Documentation
◆ 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 63 of file qgsnetworkcontentfetchertask.cpp.
◆ fetched
|
signal |
Emitted when the network content has been fetched, regardless of whether the fetch was successful or not.
Users of QgsNetworkContentFetcherTask should connect to this signal, and from the associated slot they can then safely access the network reply() without danger of the task being first removed by the QgsTaskManager.
◆ reply()
| QNetworkReply * QgsNetworkContentFetcherTask::reply | ( | ) |
Returns the network reply.
Ownership is not transferred.
May return nullptr if the request has not yet completed.
Definition at line 71 of file qgsnetworkcontentfetchertask.cpp.
◆ run()
|
overridevirtual |
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 39 of file qgsnetworkcontentfetchertask.cpp.
The documentation for this class was generated from the following files:
- /tmp/buildd/qgis-3.8.0+99unstable/src/core/qgsnetworkcontentfetchertask.h
- /tmp/buildd/qgis-3.8.0+99unstable/src/core/qgsnetworkcontentfetchertask.cpp
