Merge pull request #5027 from boundlessgeo/gpkg-vector-delete

[feature][needs-docs] Adds delete layer context action to ogr and geopackage items

src/providers/ogr/qgsgeopackagedataitems.cpp

@@ -20,13 +20,16 @@
 #include "qgsproject.h"
 #include "qgsvectorlayer.h"
 #include "qgsrasterlayer.h"
+#include "qgsogrprovider.h"
 #include "qgsnewgeopackagelayerdialog.h"
 
 #include <QAction>
 #include <QMessageBox>
 #include <QFileDialog>
 #include <QInputDialog>
 
+QGISEXTERN bool deleteLayer( const QString &uri, const QString &errCause );
+
 QgsDataItem *QgsGeoPackageDataItemProvider::createDataItem( const QString &path, QgsDataItem *parentItem )
 {
   QgsDebugMsg( "path = " + path );
@@ -327,7 +330,6 @@ void QgsGeoPackageConnectionItem::addTable()
 QList<QAction *> QgsGeoPackageAbstractLayerItem::actions()
 {
   QList<QAction *> lst;
-
   // TODO: delete layer when the provider supports it (not currently implemented)
   return lst;
 }
@@ -352,3 +354,55 @@ QgsGeoPackageRasterLayerItem::QgsGeoPackageRasterLayerItem( QgsDataItem *parent,
 {
 
 }
+
+
+#ifdef HAVE_GUI
+QList<QAction *> QgsGeoPackageVectorLayerItem::actions()
+{
+  QList<QAction *> lst = QgsGeoPackageAbstractLayerItem::actions();
+  QAction *actionDeleteLayer = new QAction( tr( "Delete layer '%1'..." ).arg( mName ), this );
+  connect( actionDeleteLayer, &QAction::triggered, this, &QgsGeoPackageVectorLayerItem::deleteLayer );
+  lst.append( actionDeleteLayer );
+  return lst;
+}
+
+
+void QgsGeoPackageVectorLayerItem::deleteLayer()
+{
+  // Check if the layer is in the registry
+  const QgsMapLayer *projectLayer = nullptr;
+  Q_FOREACH ( const QgsMapLayer *layer, QgsProject::instance()->mapLayers() )
+  {
+    if ( layer->publicSource() == mUri )
+    {
+      projectLayer = layer;
+    }
+  }
+  if ( ! projectLayer )
+  {
+    if ( QMessageBox::question( nullptr, QObject::tr( "Delete Layer" ),
+                                QObject::tr( "Are you sure you want to delete layer '%1' from GeoPackage?" ).arg( mName ),
+                                QMessageBox::Yes | QMessageBox::No, QMessageBox::No ) != QMessageBox::Yes )
+      return;
+
+    QString errCause;
+    bool res = ::deleteLayer( mUri, errCause );
+    if ( !res )
+    {
+      QMessageBox::warning( nullptr, tr( "Delete Layer" ), errCause );
+    }
+    else
+    {
+      QMessageBox::information( nullptr, tr( "Delete Layer" ), tr( "Layer deleted successfully." ) );
+      if ( mParent )
+        mParent->refresh();
+    }
+  }
+  else
+  {
+    QMessageBox::warning( nullptr, QObject::tr( "Delete Layer" ), QObject::tr( "The layer '%1' cannot be deleted because it is in the current project as '%2',"
+                          " remove it from the project and retry." ).arg( mName, projectLayer->name() ) );
+  }
+}
+#endif
+

src/providers/ogr/qgsgeopackagedataitems.h

@@ -49,7 +49,11 @@ class QgsGeoPackageVectorLayerItem : public QgsGeoPackageAbstractLayerItem
     Q_OBJECT
   public:
     QgsGeoPackageVectorLayerItem( QgsDataItem *parent, QString name, QString path, QString uri, LayerType layerType );
-
+#ifdef HAVE_GUI
+    QList<QAction *> actions() override;
+  public slots:
+    void deleteLayer();
+#endif
 };
 
 

src/providers/ogr/qgsogrdataitems.cpp

@@ -18,10 +18,12 @@
 #include "qgslogger.h"
 #include "qgsmessagelog.h"
 #include "qgssettings.h"
+#include "qgsproject.h"
 
 #include <QFileInfo>
 #include <QTextStream>
 #include <QAction>
+#include <QMessageBox>
 
 #include <ogr_srs_api.h>
 #include <cpl_error.h>
@@ -31,11 +33,14 @@
 QGISEXTERN QStringList fileExtensions();
 QGISEXTERN QStringList wildcards();
 
+QGISEXTERN bool deleteLayer( const QString &uri, const QString &errCause );
+
 
 QgsOgrLayerItem::QgsOgrLayerItem( QgsDataItem *parent,
-                                  QString name, QString path, QString uri, LayerType layerType )
+                                  QString name, QString path, QString uri, LayerType layerType, bool isSubLayer )
   : QgsLayerItem( parent, name, path, uri, layerType, QStringLiteral( "ogr" ) )
 {
+  mIsSubLayer = isSubLayer;
   mToolTip = uri;
   setState( Populated ); // children are not expected
 
@@ -56,6 +61,7 @@ QgsOgrLayerItem::QgsOgrLayerItem( QgsDataItem *parent,
   }
 }
 
+
 bool QgsOgrLayerItem::setCrs( const QgsCoordinateReferenceSystem &crs )
 {
   if ( !( mCapabilities & SetCrs ) )
@@ -110,9 +116,71 @@ QString QgsOgrLayerItem::layerName() const
     return info.completeBaseName();
 }
 
+#ifdef HAVE_GUI
+QList<QAction *> QgsOgrLayerItem::actions()
+{
+  QList<QAction *> lst;
+  // Messages are different for files and tables
+  QString message = mIsSubLayer ? QObject::tr( "Delete layer '%1'..." ).arg( mName ) : QObject::tr( "Delete file '%1'..." ).arg( mUri );
+  QAction *actionDeleteLayer = new QAction( message, this );
+  connect( actionDeleteLayer, &QAction::triggered, this, &QgsOgrLayerItem::deleteLayer );
+  lst.append( actionDeleteLayer );
+  return lst;
+}
+
+void QgsOgrLayerItem::deleteLayer()
+{
+  // Messages are different for files and tables
+  QString title = mIsSubLayer ? QObject::tr( "Delete Layer" ) : QObject::tr( "Delete File" );
+  // Check if the layer is in the registry
+  const QgsMapLayer *projectLayer = nullptr;
+  Q_FOREACH ( const QgsMapLayer *layer, QgsProject::instance()->mapLayers() )
+  {
+    if ( layer->publicSource() == mUri )
+    {
+      projectLayer = layer;
+    }
+  }
+  if ( ! projectLayer )
+  {
+    QString confirmMessage;
+    if ( mIsSubLayer )
+    {
+      confirmMessage = QObject::tr( "Are you sure you want to delete layer '%1' from datasource?" ).arg( mName );
+    }
+    else
+    {
+      confirmMessage = QObject::tr( "Are you sure you want to delete file '%1'?" ).arg( mUri );
+    }
+    if ( QMessageBox::question( nullptr, title,
+                                confirmMessage,
+                                QMessageBox::Yes | QMessageBox::No, QMessageBox::No ) != QMessageBox::Yes )
+      return;
+
+    QString errCause;
+    bool res = ::deleteLayer( mUri, errCause );
+    if ( !res )
+    {
+      QMessageBox::warning( nullptr, title, errCause );
+    }
+    else
+    {
+      QMessageBox::information( nullptr, title, mIsSubLayer ? tr( "Layer deleted successfully." ) :  tr( "File deleted successfully." ) );
+      if ( mParent )
+        mParent->refresh();
+    }
+  }
+  else
+  {
+    QMessageBox::warning( nullptr, title, QObject::tr( "The layer '%1' cannot be deleted because it is in the current project as '%2',"
+                          " remove it from the project and retry." ).arg( mName, projectLayer->name() ) );
+  }
+}
+#endif
+
 // -------
 
-static QgsOgrLayerItem *dataItemForLayer( QgsDataItem *parentItem, QString name, QString path, OGRDataSourceH hDataSource, int layerId )
+static QgsOgrLayerItem *dataItemForLayer( QgsDataItem *parentItem, QString name, QString path, OGRDataSourceH hDataSource, int layerId, bool isSubLayer = false )
 {
   OGRLayerH hLayer = OGR_DS_GetLayer( hDataSource, layerId );
   OGRFeatureDefnH hDef = OGR_L_GetLayerDefn( hLayer );
@@ -166,7 +234,7 @@ static QgsOgrLayerItem *dataItemForLayer( QgsDataItem *parentItem, QString name,
 
   QgsDebugMsgLevel( "OGR layer uri : " + layerUri, 2 );
 
-  return new QgsOgrLayerItem( parentItem, name, path, layerUri, layerType );
+  return new QgsOgrLayerItem( parentItem, name, path, layerUri, layerType, isSubLayer );
 }
 
 // ----
@@ -189,7 +257,7 @@ QVector<QgsDataItem *> QgsOgrDataCollectionItem::createChildren()
   children.reserve( numLayers );
   for ( int i = 0; i < numLayers; ++i )
   {
-    QgsOgrLayerItem *item = dataItemForLayer( this, QString(), mPath, hDataSource, i );
+    QgsOgrLayerItem *item = dataItemForLayer( this, QString(), mPath, hDataSource, i, true );
     children.append( item );
   }
 

src/providers/ogr/qgsogrdataitems.h

@@ -24,11 +24,19 @@ class QgsOgrLayerItem : public QgsLayerItem
 {
     Q_OBJECT
   public:
-    QgsOgrLayerItem( QgsDataItem *parent, QString name, QString path, QString uri, LayerType layerType );
+    QgsOgrLayerItem( QgsDataItem *parent, QString name, QString path, QString uri, LayerType layerType, bool isSubLayer = false );
 
     bool setCrs( const QgsCoordinateReferenceSystem &crs ) override;
 
     QString layerName() const override;
+
+#ifdef HAVE_GUI
+    QList<QAction *> actions() override;
+  public slots:
+    void deleteLayer();
+#endif
+  private:
+    bool mIsSubLayer;
 };
 
 

src/providers/ogr/qgsogrprovider.cpp

@@ -4297,3 +4297,76 @@ QGISEXTERN void cleanupProvider()
   // NOTE: QgsApplication takes care of
   // calling OGRCleanupAll();
 }
+
+
+
+QGISEXTERN bool deleteLayer( const QString &uri, QString &errCause )
+{
+  bool isSubLayer;
+  int layerIndex;
+  QString layerName;
+  QString subsetString;
+  OGRwkbGeometryType ogrGeometryType;
+  QString filePath = AnalyzeURI( uri,
+                                 isSubLayer,
+                                 layerIndex,
+                                 layerName,
+                                 subsetString,
+                                 ogrGeometryType );
+
+  OGRDataSourceH hDS = GDALOpenEx( filePath.toLocal8Bit().data(), GDAL_OF_RASTER | GDAL_OF_VECTOR | GDAL_OF_UPDATE, NULL, NULL, NULL );
+  if ( hDS  && ( ! layerName.isEmpty() || layerIndex != -1 ) )
+  {
+    if ( layerIndex == -1 )
+    {
+      for ( int i = 0; i < GDALDatasetGetLayerCount( hDS ); i++ )
+      {
+        OGRLayerH hL = GDALDatasetGetLayer( hDS, i );
+        if ( layerName == QString( OGR_L_GetName( hL ) ) )
+        {
+          layerIndex = i;
+        }
+      }
+    }
+    OGRErr error = GDALDatasetDeleteLayer( hDS, layerIndex );
+    switch ( error )
+    {
+      case OGRERR_NOT_ENOUGH_DATA:
+        errCause = QObject::tr( "Not enough data to deserialize" );
+        break;
+      case OGRERR_NOT_ENOUGH_MEMORY:
+        errCause = QObject::tr( "Not enough memory" );
+        break;
+      case OGRERR_UNSUPPORTED_GEOMETRY_TYPE:
+        errCause = QObject::tr( "Unsupported geometry type" );
+        break;
+      case OGRERR_UNSUPPORTED_OPERATION:
+        errCause = QObject::tr( "Unsupported operation" );
+        break;
+      case OGRERR_CORRUPT_DATA:
+        errCause = QObject::tr( "Corrupt data" );
+        break;
+      case OGRERR_FAILURE:
+        errCause = QObject::tr( "Failure" );
+        break;
+      case OGRERR_UNSUPPORTED_SRS:
+        errCause = QObject::tr( "Unsupported SRS" );
+        break;
+      case OGRERR_INVALID_HANDLE:
+        errCause = QObject::tr( "Invalid handle" );
+        break;
+      case OGRERR_NON_EXISTING_FEATURE:
+        errCause = QObject::tr( "Non existing feature" );
+        break;
+      default:
+      case OGRERR_NONE:
+        errCause = QObject::tr( "Success" );
+        break;
+    }
+    errCause = QObject::tr( "GDAL result code: %s" ).arg( errCause );
+    return error == OGRERR_NONE;
+  }
+  // This should never happen:
+  errCause = QObject::tr( "Layer not found: %s" ).arg( uri );
+  return false;
+}