Respect QgsTask::CanCancel flag in gui

Author: nyalldawson

python/core/__init__.py

@@ -199,12 +199,12 @@ def copy_func(f):
 
 class QgsTaskWrapper(QgsTask):
 
-    def __init__(self, description, function, on_finished, *args, **kwargs):
-        QgsTask.__init__(self, description)
+    def __init__(self, description, flags, function, on_finished, *args, **kwargs):
+        QgsTask.__init__(self, description, flags)
         self.args = args
         self.kwargs = kwargs
         self.function = copy_func(function)
-        self.on_finished = copy_func(on_finished)
+        self.on_finished = copy_func(on_finished) if on_finished else None
         self.returned_values = None
         self.exception = None
 
@@ -235,7 +235,8 @@ def finished(self, result):
             self.exception = ex
 
 
-def fromFunction(cls, description, function, *args, on_finished=None, **kwargs):
-    return QgsTaskWrapper(description, function, on_finished, *args, **kwargs)
+def fromFunction(cls, description, function, *args, on_finished=None, flags=QgsTask.AllFlags, **kwargs):
+    assert function
+    return QgsTaskWrapper(description, flags, function, on_finished, *args, **kwargs)
 
 QgsTask.fromFunction = classmethod(fromFunction)

src/core/qgstaskmanager.cpp

@@ -87,20 +87,22 @@ void QgsTask::run()
 
 void QgsTask::cancel()
 {
-#if QT_VERSION < 0x050500
-  //can't cancel with qt < 5.5
-  return;
-#else
+  if ( mOverallStatus == Complete || mOverallStatus == Terminated )
+    return;
 
   mShouldTerminate = true;
-  QThreadPool::globalInstance()->cancel( this );
 
+#if QT_VERSION >= 0x050500
+  //can't cancel queued tasks with qt < 5.5
+  QThreadPool::globalInstance()->cancel( this );
   if ( mStatus == Queued || mStatus == OnHold )
   {
     // immediately terminate unstarted jobs
     terminated();
   }
-  else if ( mStatus == Terminated )
+#endif
+
+  if ( mStatus == Terminated )
   {
     processSubTasksForTermination();
   }
@@ -109,7 +111,6 @@ void QgsTask::cancel()
   {
     subTask.task->cancel();
   }
-#endif
 }
 
 void QgsTask::hold()

src/gui/qgstaskmanagerwidget.cpp

@@ -37,12 +37,6 @@ QgsTaskManagerWidget::QgsTaskManagerWidget( QgsTaskManager *manager, QWidget *pa
 
   QVBoxLayout* vLayout = new QVBoxLayout();
   vLayout->setMargin( 0 );
-#if 0
-  QToolBar* toolbar = new QToolBar();
-  toolbar->setIconSize( QSize( 16, 16 ) );
-  toolbar->addAction( new QAction( "test", this ) );
-  vLayout->addWidget( toolbar );
-#endif
   mTreeView = new QTreeView();
   mModel = new QgsTaskManagerModel( manager, this );
   mTreeView->setModel( mModel );
@@ -54,7 +48,6 @@ QgsTaskManagerWidget::QgsTaskManagerWidget( QgsTaskManager *manager, QWidget *pa
 
   vLayout->addWidget( mTreeView );
 
-
   setLayout( vLayout );
 }
 
@@ -202,10 +195,11 @@ Qt::ItemFlags QgsTaskManagerModel::flags( const QModelIndex &index ) const
     return flags;
   }
 
+  QgsTask* task = indexToTask( index );
   if ( index.column() == Status )
   {
-    //if ( static_cast< QgsTask::TaskStatus >( data( index, StatusRole ).toInt() ) == QgsTask::Running )
-    flags = flags | Qt::ItemIsEditable;
+    if ( task && task->canCancel() )
+      flags = flags | Qt::ItemIsEditable;
   }
   return flags | Qt::ItemIsEnabled | Qt::ItemIsSelectable;
 }
@@ -225,7 +219,7 @@ bool QgsTaskManagerModel::setData( const QModelIndex &index, const QVariant &val
   {
     case Status:
     {
-      if ( value.toBool() )
+      if ( value.toBool() && task->canCancel() )
         task->cancel();
       return true;
     }
@@ -388,8 +382,8 @@ QgsTaskManagerFloatingWidget::QgsTaskManagerFloatingWidget( QgsTaskManager *mana
     : QgsFloatingWidget( parent )
 {
   setLayout( new QVBoxLayout() );
-  setMinimumSize( 250, 150 );
   QgsTaskManagerWidget* w = new QgsTaskManagerWidget( manager );
+  setMinimumSize( w->sizeHint() );
   layout()->addWidget( w );
   setStyleSheet( ".QgsTaskManagerFloatingWidget { border-top-left-radius: 8px;"
                  "border-top-right-radius: 8px; background-color: rgb(0, 0, 0, 70%); }" );

tests/src/python/test_qgstaskmanager.py

@@ -110,6 +110,14 @@ def testTaskFromFunction(self):
         self.assertTrue(bad_task.exception)
         self.assertEqual(bad_task.status(), QgsTask.Terminated)
 
+    def testTaskFromFunctionWithFlags(self):
+        """ test creating task from function with flags"""
+
+        task = QgsTask.fromFunction('test task', run, 20, flags=QgsTask.Flags())
+        self.assertFalse(task.canCancel())
+        task2 = QgsTask.fromFunction('test task', run, 20, flags=QgsTask.CanCancel)
+        self.assertTrue(task2.canCancel())
+
     def testTaskFromFunctionWithKwargs(self):
         """ test creating task from function using kwargs """