Standardise API for deciding whether the datum transform dialog shoul…

…d be shown
qgis · Mar 22, 2019 · 0b6fdd9 · 0b6fdd9
1 parent fc4d9b8
commit 0b6fdd9
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Showing 3 changed files with 21 additions and 11 deletions.
diff --git a/src/app/qgisapp.cpp b/src/app/qgisapp.cpp
@@ -7855,8 +7855,7 @@ QString QgisApp::saveAsVectorFileGeneral( QgsVectorLayer *vlayer, bool symbology
       //ask user about datum transformation
       QgsSettings settings;
       QgsDatumTransformDialog dlg( vlayer->crs(), destCRS );
-      if ( dlg.availableTransformationCount() > 1 &&
-           settings.value( QStringLiteral( "Projections/showDatumTransformDialog" ), false ).toBool() )
+      if ( dlg.shouldAskUserForSelection() )
       {
         dlg.exec();
       }
@@ -9912,6 +9911,7 @@ void QgisApp::projectCrsChanged()
   }
   else if ( transformsToAskFor.count() > 1 )
   {
+    // TODO - this should actually loop through and ask for each in turn
     bool ask = QgsSettings().value( QStringLiteral( "/Projections/showDatumTransformDialog" ), false ).toBool();
     if ( ask )
     {
@@ -9921,8 +9921,6 @@ void QgisApp::projectCrsChanged()
                                         5 );
     }
   }
-
-
 }
 
 // toggle overview status
@@ -13736,14 +13734,9 @@ bool QgisApp::askUserForDatumTransform( const QgsCoordinateReferenceSystem &sour
   {
     //if several possibilities:  present dialog
     QgsDatumTransformDialog dlg( sourceCrs, destinationCrs );
-    if ( dlg.availableTransformationCount() > 1 )
+    if ( dlg.shouldAskUserForSelection() )
     {
-      bool ask = QgsSettings().value( QStringLiteral( "/Projections/showDatumTransformDialog" ), false ).toBool();
-      if ( !ask )
-      {
-        ok = false;
-      }
-      else if ( dlg.exec() )
+      if ( dlg.exec() )
       {
         QPair< QPair<QgsCoordinateReferenceSystem, int>, QPair<QgsCoordinateReferenceSystem, int > > dt = dlg.selectedDatumTransforms();
         QgsCoordinateTransformContext context = QgsProject::instance()->transformContext();

diff --git a/src/gui/qgsdatumtransformdialog.cpp b/src/gui/qgsdatumtransformdialog.cpp
@@ -195,6 +195,16 @@ int QgsDatumTransformDialog::availableTransformationCount()
   return mDatumTransforms.count();
 }
 
+bool QgsDatumTransformDialog::shouldAskUserForSelection()
+{
+  if ( availableTransformationCount() > 1 )
+  {
+    return QgsSettings().value( QStringLiteral( "/Projections/showDatumTransformDialog" ), false ).toBool();
+  }
+  // TODO: show if transform grids are required, but missing
+  return false;
+}
+
 QPair<QPair<QgsCoordinateReferenceSystem, int>, QPair<QgsCoordinateReferenceSystem, int> > QgsDatumTransformDialog::selectedDatumTransforms()
 {
   int row = mDatumTransformTableWidget->currentRow();

diff --git a/src/gui/qgsdatumtransformdialog.h b/src/gui/qgsdatumtransformdialog.h
@@ -54,6 +54,13 @@ class GUI_EXPORT QgsDatumTransformDialog : public QDialog, private Ui::QgsDatumT
      */
     int availableTransformationCount();
 
+    /**
+     * Returns true if the dialog should be shown and the user prompted to make the transformation selection.
+     *
+     * \since QGIS 3.8
+     */
+    bool shouldAskUserForSelection();
+
     /**
      * Returns the source and destination transforms, each being a pair of QgsCoordinateReferenceSystems and datum transform code
      * \since 3.0