save current extent and CRS in locator core

remove remaining bits of interface

python/core/auto_generated/locator/qgslocatorwidgetcore.sip.in

@@ -28,11 +28,6 @@ to be used in a locator widget.
     explicit QgsLocatorWidgetCore( QObject *parent = 0 );
 %Docstring
 Constructor of QgsLocatorWidgetCore
-%End
-
-    void setMapCanvasInterface( QgsMapCanvasInterface *canvasInterface );
-%Docstring
-Set the map canvas interface
 %End
 
     void performSearch( const QString &text );
@@ -80,6 +75,16 @@ Emitted when the results are cleared
     void invalidateResults();
 %Docstring
 This will invalidate current search results
+%End
+
+    void updateCanvasExtent( const QgsRectangle &extent );
+%Docstring
+Update the canvas extent used to create search context
+%End
+
+    void updateCanvasCrs( const QgsCoordinateReferenceSystem &crs );
+%Docstring
+Update the canvas CRS used to create search context
 %End
 
 };

src/core/locator/qgslocatorwidgetcore.cpp

@@ -18,7 +18,6 @@
 #include "qgslocatorwidgetcore.h"
 #include "qgslocator.h"
 #include "qgslocatormodel.h"
-#include "qgsmapcanvasinterface.h"
 #include "qgsmapsettings.h"
 
 QgsLocatorWidgetCore::QgsLocatorWidgetCore( QObject *parent )
@@ -33,11 +32,6 @@ QgsLocatorWidgetCore::QgsLocatorWidgetCore( QObject *parent )
   connect( mLocator, &QgsLocator::finished, this, &QgsLocatorWidgetCore::searchFinished );
 }
 
-void QgsLocatorWidgetCore::setMapCanvasInterface( QgsMapCanvasInterface *canvasInterface )
-{
-  mCanvasInterface = canvasInterface;
-}
-
 bool QgsLocatorWidgetCore::isRunning() const
 {
   return mIsRunning;
@@ -58,6 +52,16 @@ void QgsLocatorWidgetCore::invalidateResults()
   mLocatorModel->clear();
 }
 
+void QgsLocatorWidgetCore::updateCanvasExtent( const QgsRectangle &extent )
+{
+  mCanvasExtent = extent;
+}
+
+void QgsLocatorWidgetCore::updateCanvasCrs( const QgsCoordinateReferenceSystem &crs )
+{
+  mCanvasCrs = crs;
+}
+
 void QgsLocatorWidgetCore::addResult( const QgsLocatorResult &result )
 {
   mLocatorModel->addResult( result );
@@ -121,10 +125,7 @@ bool QgsLocatorWidgetCore::hasQueueRequested() const
 QgsLocatorContext QgsLocatorWidgetCore::createContext()
 {
   QgsLocatorContext context;
-  if ( mCanvasInterface )
-  {
-    context.targetExtent = mCanvasInterface->mapSettings().visibleExtent();
-    context.targetExtentCrs = mCanvasInterface->mapSettings().destinationCrs();
-  }
+  context.targetExtent = mCanvasExtent;
+  context.targetExtentCrs = mCanvasCrs;
   return context;
 }

src/core/locator/qgslocatorwidgetcore.h

@@ -21,13 +21,14 @@
 #include <QObject>
 
 #include "qgis_core.h"
+#include "qgscoordinatereferencesystem.h"
+#include "qgsrectangle.h"
 
 class QgsLocatorResult;
 class QgsLocator;
 class QgsLocatorContext;
 class QgsLocatorModel;
 class QgsLocatorProxyModel;
-class QgsMapCanvasInterface;
 
 
 /**
@@ -44,9 +45,6 @@ class CORE_EXPORT QgsLocatorWidgetCore : public QObject
     //! Constructor of QgsLocatorWidgetCore
     explicit QgsLocatorWidgetCore( QObject *parent = nullptr );
 
-    //! Set the map canvas interface
-    void setMapCanvasInterface( QgsMapCanvasInterface *canvasInterface );
-
     //! Perform a search
     Q_INVOKABLE void performSearch( const QString &text );
 
@@ -76,6 +74,12 @@ class CORE_EXPORT QgsLocatorWidgetCore : public QObject
     //! This will invalidate current search results
     void invalidateResults();
 
+    //! Update the canvas extent used to create search context
+    void updateCanvasExtent( const QgsRectangle &extent );
+
+    //! Update the canvas CRS used to create search context
+    void updateCanvasCrs( const QgsCoordinateReferenceSystem &crs );
+
   private slots:
     void searchFinished();
     void addResult( const QgsLocatorResult &result );
@@ -87,11 +91,17 @@ class CORE_EXPORT QgsLocatorWidgetCore : public QObject
     QgsLocator *mLocator = nullptr;
     QgsLocatorModel *mLocatorModel = nullptr;
     QgsLocatorProxyModel *mProxyModel = nullptr;
-    QgsMapCanvasInterface *mCanvasInterface = nullptr;
 
     QString mNextRequestedString;
     bool mHasQueuedRequest = false;
     bool mIsRunning = false;
+
+    // keep track of map canvas extent and CRS
+    // if much if needed, it would be possible to add
+    // a QgsMapCanvasController in core to achieve this
+    // see discussion in https://github.com/qgis/QGIS/pull/8404
+    QgsRectangle mCanvasExtent;
+    QgsCoordinateReferenceSystem mCanvasCrs;
 };
 
 #endif // QGSLOCATORWIDGETCORE_H

src/gui/locator/qgslocatorwidget.cpp

@@ -116,7 +116,22 @@ QgsLocator *QgsLocatorWidget::locator()
 
 void QgsLocatorWidget::setMapCanvas( QgsMapCanvas *canvas )
 {
-  mWidgetCore->setMapCanvasInterface( canvas );
+  if ( mMapCanvas == canvas )
+    return;
+
+  for ( const QMetaObject::Connection &conn : qgis::as_const( mCanvasConnections ) )
+  {
+    disconnect( conn );
+  }
+  mCanvasConnections.clear();
+
+  mMapCanvas = canvas;
+  if ( mMapCanvas )
+  {
+    mCanvasConnections
+    << connect( mMapCanvas, &QgsMapCanvas::extentsChanged, this, [ = ]() {mWidgetCore->updateCanvasExtent( mMapCanvas->extent() );} )
+    << connect( mMapCanvas, &QgsMapCanvas::destinationCrsChanged, this, [ = ]() {mWidgetCore->updateCanvasCrs( mMapCanvas->mapSettings().destinationCrs() );} ) ;
+  }
 }
 
 void QgsLocatorWidget::search( const QString &string )

src/gui/locator/qgslocatorwidget.h

@@ -101,6 +101,7 @@ class GUI_EXPORT QgsLocatorWidget : public QWidget
     QgsFloatingWidget *mResultsContainer = nullptr;
     QgsLocatorResultsView *mResultsView = nullptr;
     QgsMapCanvas *mMapCanvas = nullptr;
+    QList<QMetaObject::Connection> mCanvasConnections;
     QMenu *mMenu = nullptr;
 
     QTimer mFocusTimer;