Add signals for when layout item map crs or grid crs are changed

qgis · Nov 22, 2020 · 494bf24 · 494bf24
1 parent 1b56825
commit 494bf24
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Showing 8 changed files with 147 additions and 7 deletions.
diff --git a/python/core/auto_generated/layout/qgslayoutitemmap.sip.in b/python/core/auto_generated/layout/qgslayoutitemmap.sip.in
@@ -988,6 +988,13 @@ Emitted when the map's associated ``theme`` is changed.
    is linked to a different theme then it previously was.
 
 .. versionadded:: 3.14
+%End
+
+    void crsChanged();
+%Docstring
+Emitted when the map's coordinate reference system is changed.
+
+.. versionadded:: 3.18
 %End
 
   public slots:

diff --git a/python/core/auto_generated/layout/qgslayoutitemmapgrid.sip.in b/python/core/auto_generated/layout/qgslayoutitemmapgrid.sip.in
@@ -1118,6 +1118,15 @@ Retrieves the second fill color for the grid frame.
     virtual void refresh();
 
 
+  signals:
+
+    void crsChanged();
+%Docstring
+Emitted whenever the grid's CRS is changed.
+
+.. versionadded:: 3.18
+%End
+
 };
 
 QFlags<QgsLayoutItemMapGrid::FrameSideFlag> operator|(QgsLayoutItemMapGrid::FrameSideFlag f1, QFlags<QgsLayoutItemMapGrid::FrameSideFlag> f2);

diff --git a/src/core/layout/qgslayoutitemmap.cpp b/src/core/layout/qgslayoutitemmap.cpp
@@ -300,7 +300,11 @@ QgsCoordinateReferenceSystem QgsLayoutItemMap::crs() const
 
 void QgsLayoutItemMap::setCrs( const QgsCoordinateReferenceSystem &crs )
 {
+  if ( mCrs == crs )
+    return;
+
   mCrs = crs;
+  emit crsChanged();
 }
 
 QList<QgsMapLayer *> QgsLayoutItemMap::layers() const
@@ -707,15 +711,13 @@ bool QgsLayoutItemMap::readPropertiesFromElement( const QDomElement &itemElem, c
   }
 
   QDomNodeList crsNodeList = itemElem.elementsByTagName( QStringLiteral( "crs" ) );
+  QgsCoordinateReferenceSystem crs;
   if ( !crsNodeList.isEmpty() )
   {
     QDomElement crsElem = crsNodeList.at( 0 ).toElement();
-    mCrs.readXml( crsElem );
-  }
-  else
-  {
-    mCrs = QgsCoordinateReferenceSystem();
+    crs.readXml( crsElem );
   }
+  setCrs( crs );
 
   //map rotation
   mMapRotation = itemElem.attribute( QStringLiteral( "mapRotation" ), QStringLiteral( "0" ) ).toDouble();
@@ -1856,9 +1858,15 @@ void QgsLayoutItemMap::refreshDataDefinedProperty( const QgsLayoutObject::DataDe
   if ( property == QgsLayoutObject::MapCrs || property == QgsLayoutObject::AllProperties )
   {
     bool ok;
-    QString crsVar = mDataDefinedProperties.valueAsString( QgsLayoutObject::MapCrs, context, QString(), &ok );
+    const QString crsVar = mDataDefinedProperties.valueAsString( QgsLayoutObject::MapCrs, context, QString(), &ok );
     if ( ok && QgsCoordinateReferenceSystem( crsVar ).isValid() )
-      mCrs = QgsCoordinateReferenceSystem( crsVar );
+    {
+      const QgsCoordinateReferenceSystem newCrs( crsVar );
+      if ( newCrs.isValid() )
+      {
+        setCrs( newCrs );
+      }
+    }
   }
   //updates data defined properties and redraws item to match
   if ( property == QgsLayoutObject::MapRotation || property == QgsLayoutObject::MapScale ||
@@ -1992,6 +2000,7 @@ void QgsLayoutItemMap::connectUpdateSlot()
       {
         //using project CRS, which just changed....
         invalidateCache();
+        emit crsChanged();
       }
     } );
 

diff --git a/src/core/layout/qgslayoutitemmap.h b/src/core/layout/qgslayoutitemmap.h
@@ -910,6 +910,13 @@ class CORE_EXPORT QgsLayoutItemMap : public QgsLayoutItem, public QgsTemporalRan
      */
     void themeChanged( const QString &theme );
 
+    /**
+     * Emitted when the map's coordinate reference system is changed.
+     *
+     * \since QGIS 3.18
+     */
+    void crsChanged();
+
   public slots:
 
     void refresh() override;

diff --git a/src/core/layout/qgslayoutitemmapgrid.cpp b/src/core/layout/qgslayoutitemmapgrid.cpp
@@ -203,6 +203,11 @@ QgsLayoutItemMapGrid::QgsLayoutItemMapGrid( const QString &name, QgsLayoutItemMa
 
   connect( mMap, &QgsLayoutItemMap::extentChanged, this, &QgsLayoutItemMapGrid::refreshDataDefinedProperties );
   connect( mMap, &QgsLayoutItemMap::mapRotationChanged, this, &QgsLayoutItemMapGrid::refreshDataDefinedProperties );
+  connect( mMap, &QgsLayoutItemMap::crsChanged, this, [ = ]
+  {
+    if ( !mCRS.isValid() )
+      emit crsChanged();
+  } );
 }
 
 void QgsLayoutItemMapGrid::createDefaultGridLineSymbol()
@@ -438,8 +443,12 @@ bool QgsLayoutItemMapGrid::readXml( const QDomElement &itemElem, const QDomDocum
 
 void QgsLayoutItemMapGrid::setCrs( const QgsCoordinateReferenceSystem &crs )
 {
+  if ( mCRS == crs )
+    return;
+
   mCRS = crs;
   mTransformDirty = true;
+  emit crsChanged();
 }
 
 bool QgsLayoutItemMapGrid::usesAdvancedEffects() const

diff --git a/src/core/layout/qgslayoutitemmapgrid.h b/src/core/layout/qgslayoutitemmapgrid.h
@@ -1006,6 +1006,15 @@ class CORE_EXPORT QgsLayoutItemMapGrid : public QgsLayoutItemMapItem
     bool accept( QgsStyleEntityVisitorInterface *visitor ) const override;
     void refresh() override;
 
+  signals:
+
+    /**
+     * Emitted whenever the grid's CRS is changed.
+     *
+     * \since QGIS 3.18
+     */
+    void crsChanged();
+
   private:
 
     QgsLayoutItemMapGrid() = delete;

diff --git a/tests/src/python/test_qgslayoutmap.py b/tests/src/python/test_qgslayoutmap.py
@@ -822,6 +822,44 @@ def testMainAnnotationLayer(self):
         TestQgsLayoutMap.report += checker.report()
         self.assertTrue(result, message)
 
+    def testCrsChanged(self):
+        """
+        Test that the CRS changed signal is emitted in the right circumstances
+        """
+        p = QgsProject()
+        layout = QgsLayout(p)
+        p.setCrs(QgsCoordinateReferenceSystem('EPSG:4326'))
+        map = QgsLayoutItemMap(layout)
+
+        spy = QSignalSpy(map.crsChanged)
+        # map has no explicit crs set, so follows project crs => signal should be emitted
+        # when project crs is changed
+        p.setCrs(QgsCoordinateReferenceSystem('EPSG:3111'))
+        self.assertEqual(len(spy), 1)
+        p.setCrs(QgsCoordinateReferenceSystem('EPSG:4326'))
+        self.assertEqual(len(spy), 2)
+        # set explicit crs on map item
+        map.setCrs(QgsCoordinateReferenceSystem('EPSG:28356'))
+        self.assertEqual(len(spy), 3)
+        map.setCrs(QgsCoordinateReferenceSystem('EPSG:28356'))
+        self.assertEqual(len(spy), 3)
+        map.setCrs(QgsCoordinateReferenceSystem('EPSG:28355'))
+        self.assertEqual(len(spy), 4)
+        # should not care about project crs changes anymore..
+        p.setCrs(QgsCoordinateReferenceSystem('EPSG:3111'))
+        self.assertEqual(len(spy), 4)
+        # set back to project crs
+        map.setCrs(QgsCoordinateReferenceSystem())
+        self.assertEqual(len(spy), 5)
+
+        map.setCrs(QgsCoordinateReferenceSystem('EPSG:28355'))
+        self.assertEqual(len(spy), 6)
+        # data defined crs
+        map.dataDefinedProperties().setProperty(QgsLayoutObject.MapCrs, QgsProperty.fromValue('EPSG:4283'))
+        self.assertEqual(len(spy), 6)
+        map.refresh()
+        self.assertEqual(len(spy), 7)
+
 
 if __name__ == '__main__':
     unittest.main()
diff --git a/tests/src/python/test_qgslayoutmapgrid.py b/tests/src/python/test_qgslayoutmapgrid.py
@@ -14,6 +14,7 @@
 
 from qgis.PyQt.QtCore import QRectF, QDir
 from qgis.PyQt.QtGui import QPainter, QColor
+from qgis.PyQt.QtTest import QSignalSpy
 
 from qgis.core import (QgsLayoutItemMap,
                        QgsLayoutItemMapGrid,
@@ -852,6 +853,57 @@ def testDynamicInterval(self):
         self.report += checker.report()
         self.assertTrue(myTestResult, myMessage)
 
+    def testCrsChanged(self):
+        """
+        Test that the CRS changed signal is emitted in the right circumstances
+        """
+        p = QgsProject()
+        layout = QgsLayout(p)
+        p.setCrs(QgsCoordinateReferenceSystem('EPSG:4326'))
+        map = QgsLayoutItemMap(layout)
+
+        grid = map.grid()
+
+        spy = QSignalSpy(grid.crsChanged)
+        # map grid and map have no explicit crs set, so follows project crs => signal should be emitted
+        # when project crs is changed
+        p.setCrs(QgsCoordinateReferenceSystem('EPSG:3111'))
+        self.assertEqual(len(spy), 1)
+        p.setCrs(QgsCoordinateReferenceSystem('EPSG:4326'))
+        self.assertEqual(len(spy), 2)
+        # set explicit crs on map item
+        map.setCrs(QgsCoordinateReferenceSystem('EPSG:28356'))
+        self.assertEqual(len(spy), 3)
+        map.setCrs(QgsCoordinateReferenceSystem('EPSG:28356'))
+        self.assertEqual(len(spy), 3)
+        map.setCrs(QgsCoordinateReferenceSystem('EPSG:28355'))
+        self.assertEqual(len(spy), 4)
+        # should not care about project crs changes anymore..
+        p.setCrs(QgsCoordinateReferenceSystem('EPSG:3111'))
+        self.assertEqual(len(spy), 4)
+        # set back to project crs
+        map.setCrs(QgsCoordinateReferenceSystem())
+        self.assertEqual(len(spy), 5)
+
+        map.setCrs(QgsCoordinateReferenceSystem('EPSG:28355'))
+        self.assertEqual(len(spy), 6)
+        # data defined crs
+        map.dataDefinedProperties().setProperty(QgsLayoutObject.MapCrs, QgsProperty.fromValue('EPSG:4283'))
+        self.assertEqual(len(spy), 6)
+        map.refresh()
+        self.assertEqual(len(spy), 7)
+
+        # explicit crs for map grid
+        grid.setCrs(QgsCoordinateReferenceSystem('EPSG:3857'))
+        self.assertEqual(len(spy), 8)
+        grid.setCrs(QgsCoordinateReferenceSystem('EPSG:3857'))
+        self.assertEqual(len(spy), 8)
+        map.dataDefinedProperties().setProperty(QgsLayoutObject.MapCrs, QgsProperty.fromValue('EPSG:3111'))
+        map.refresh()
+        self.assertEqual(len(spy), 8)
+        grid.setCrs(QgsCoordinateReferenceSystem('EPSG:3111'))
+        self.assertEqual(len(spy), 9)
+
 
 if __name__ == '__main__':
     unittest.main()