QGIS » QGIS Application

/***************************************************************************

  ogrsublayers.cpp

  This plugin allows the user to choose which layers to load from an OGR multilayer datasource.

  -------------------

         begin                : [PluginDate]

         copyright            : [(C) Your Name and Date]

         email                : [Your Email]

 ***************************************************************************

 *                                                                         *

 *   This program is free software; you can redistribute it and/or modify  *

 *   it under the terms of the GNU General Public License as published by  *

 *   the Free Software Foundation; either version 2 of the License, or     *

 *   (at your option) any later version.                                   *

 *                                                                         *

 ***************************************************************************/

/*  $Id: plugin.cpp 9327 2008-09-14 11:18:44Z jef $ */

//

// QGIS Specific includes

//

#include <qgisinterface.h>

#include <qgisgui.h>

#include <qgslogger.h>

#include <qgsdataprovider.h>

#include <qgsvectordataprovider.h>

#include <qgsmaplayerregistry.h>

#include "ogrsublayers.h"

#include "ogrsublayersgui.h"

#include "../../providers/ogr/qgsogrprovider.h"

//

// Qt4 Related Includes

//

#include <QAction>

#include <QToolBar>

#include <QTableWidgetItem>

#include <QFileInfo>

#include <QMessageBox>

static const char * const sIdent = "$Id: plugin.cpp 9327 2008-09-14 11:18:44Z jef $";

static const QString sName = QObject::tr( "OGR SubLayers" );

static const QString sDescription = QObject::tr( "This plugin allows the user to choose which layers to load from an OGR multilayer datasource." );

static const QString sPluginVersion = QObject::tr( "Version 0.1" );

static const QgisPlugin::PLUGINTYPE sPluginType = QgisPlugin::UI;

//////////////////////////////////////////////////////////////////////

//

// THE FOLLOWING METHODS ARE MANDATORY FOR ALL PLUGINS

//

//////////////////////////////////////////////////////////////////////

/**

 * Constructor for the plugin. The plugin is passed a pointer

 * an interface object that provides access to exposed functions in QGIS.

 * @param theQGisInterface - Pointer to the QGIS interface object

 */

OGRSubLayers::OGRSubLayers( QgisInterface * theQgisInterface ):

    QgisPlugin( sName, sDescription, sPluginVersion, sPluginType ),

    mQGisIface( theQgisInterface )

{

}

OGRSubLayers::~OGRSubLayers()

{

}

/*

 * Initialize the GUI interface for the plugin - this is only called once when the plugin is

 * added to the plugin registry in the QGIS application.

 */

void OGRSubLayers::initGui()

{

  // Create the action for tool

  mQActionPointer = new QAction( QIcon( ":/ogrsublayers/ogrsublayers.png" ), tr( "OGR SubLayers" ), this );

  // Set the what's this text

  mQActionPointer->setWhatsThis( tr( "Replace this with a short description of what the plugin does" ) );

  // Connect the action to the run

  connect( mQActionPointer, SIGNAL( triggered() ), this, SLOT( run() ) );

  // Add the icon to the toolbar

  mQGisIface->addToolBarIcon( mQActionPointer );

  mQGisIface->addPluginToMenu( tr( "&OGR SubLayers" ), mQActionPointer );

}

//method defined in interface

void OGRSubLayers::help()

{

  //implement me!

}

// Slot called when the menu item is triggered

// If you created more menu items / toolbar buttons in initiGui, you should

// create a separate handler for each action - this single run() method will

// not be enough

void OGRSubLayers::run()

{

  OGRSubLayersGui *myPluginGui;

  if ( mQGisIface->activeLayer() )

  {

    if ( mQGisIface->activeLayer()->type() == QgsMapLayer::VectorLayer )

    {

      // This plugin is OGR specific until proved safe to use with other providers.

      if (0 == (( QgsVectorLayer *)mQGisIface->activeLayer())->dataProvider()->name().compare("ogr"))

      {

        uri=mQGisIface->activeLayer()->source();

        // If there is no & in the uri, then the uri is just the filename. The loaded

        // layer will be layer 0.

        if ( uri.contains('&', Qt::CaseSensitive))

        {

        // If we get here, there are some options added to the filename. We must parse

        // the different parts separated by &, and among each option, the name and the

        // value around the =.

        // A valid uri is of the form: filename&option1=value1&option2=value2,...

           QStringList theURIParts = uri.split("&");

          uri = theURIParts.at( 0 );

        }

        QgsOgrProvider* theCurrentProvider = ( QgsOgrProvider * )((( QgsVectorLayer *)mQGisIface->activeLayer())->dataProvider());

        // We get the subLayers of activeLayer.dataProvider and we show them in the dialogbox.

        QStringList liste = theCurrentProvider->subLayers();

        if ( liste.count() < 2)

        {

          QMessageBox *myBox = new QMessageBox( QMessageBox::Information, "No sublayers!", "There are no sublayers in the active layer. Select another layer to activate the plugin.", QMessageBox::Ok, mQGisIface->mainWindow(),Qt::MSWindowsFixedSizeDialogHint);

          myBox -> setModal(true);

          myBox -> show();

          return;

        }else

        {

          myPluginGui = new OGRSubLayersGui( mQGisIface->mainWindow(), QgisGui::ModalDialogFlags );

          myPluginGui->setAttribute( Qt::WA_DeleteOnClose );

          myPluginGui->show();

          connect( myPluginGui, SIGNAL( updated(QStringList * ) ), this, SLOT( load(QStringList *  ) ) );

          myPluginGui->populateLayerTable( & liste );

        }

        // We want to select the already selected layers so the user can choose to add or remove

        // others

        QgsMapLayerRegistry * theLayerRegistry = QgsMapLayerRegistry::instance();

        QList<QgsVectorLayer * > theVectorLayersList = QList<QgsVectorLayer * >();

        QMapIterator<QString, QgsMapLayer*> iterator(theLayerRegistry -> mapLayers());

        while (iterator.hasNext()){

          iterator.next();

          if (iterator.value()->type() == QgsMapLayer::VectorLayer){

            theVectorLayersList.append ( (QgsVectorLayer*) (iterator.value()) );

          }

        }

        QgsLogger::critical("Nb of vector layers loaded: " + QString::number( theVectorLayersList.size()));

        myPluginGui->updateSelection();

      }

    }else // activeLayer -> type != VectorLayer

    {

      QMessageBox *myBox = new QMessageBox( QMessageBox::Information, "Not a vector layer", "This plugin is OGR specific! Select another layer to activate the plugin.", QMessageBox::Ok, mQGisIface->mainWindow(),Qt::MSWindowsFixedSizeDialogHint);

      myBox -> setModal(true);

      myBox -> show();

      return;

    }

  }

}

void OGRSubLayers::load(QStringList * list)

{

  QString fileName = QFileInfo(uri).baseName();

  for (int i = 0; i < list->size(); i++)

  {

    QString composedURI=uri+"&layername="+list->at(i);    

    mQGisIface-> addVectorLayer(composedURI,fileName+":"+list->at(i),"ogr");

  }

}

// Unload the plugin by cleaning up the GUI

void OGRSubLayers::unload()

{

  // remove the GUI

  mQGisIface->removePluginMenu( "&OGR SubLayers", mQActionPointer );

  mQGisIface->removeToolBarIcon( mQActionPointer );

  delete mQActionPointer;

}

//////////////////////////////////////////////////////////////////////////

//

//

//  THE FOLLOWING CODE IS AUTOGENERATED BY THE PLUGIN BUILDER SCRIPT

//    YOU WOULD NORMALLY NOT NEED TO MODIFY THIS, AND YOUR PLUGIN

//      MAY NOT WORK PROPERLY IF YOU MODIFY THIS INCORRECTLY

//

//

//////////////////////////////////////////////////////////////////////////

/**

 * Required extern functions needed  for every plugin

 * These functions can be called prior to creating an instance

 * of the plugin class

 */

// Class factory to return a new instance of the plugin class

QGISEXTERN QgisPlugin * classFactory( QgisInterface * theQgisInterfacePointer )

{

  return new OGRSubLayers( theQgisInterfacePointer );

}

// Return the name of the plugin - note that we do not user class members as

// the class may not yet be insantiated when this method is called.

QGISEXTERN QString name()

{

  return sName;

}

// Return the description

QGISEXTERN QString description()

{

  return sDescription;

}

// Return the type (either UI or MapLayer plugin)

QGISEXTERN int type()

{

  return sPluginType;

}

// Return the version number for the plugin

QGISEXTERN QString version()

{

  return sPluginVersion;

}

// Delete ourself

QGISEXTERN void unload( QgisPlugin * thePluginPointer )

{

  delete thePluginPointer;

}

<RCC>

    <qresource prefix="/ogrsublayers/" >

        <file>ogrsublayers.png</file>

    </qresource>

</RCC>

/***************************************************************************

 *   Copyright (C) 2003 by Tim Sutton                                      *

 *   [email protected]                                                     *

 *                                                                         *

 *   This is a plugin generated from the QGIS plugin template              *

 *                                                                         *

 *   This program is free software; you can redistribute it and/or modify  *

 *   it under the terms of the GNU General Public License as published by  *

 *   the Free Software Foundation; either version 2 of the License, or     *

 *   (at your option) any later version.                                   *

 ***************************************************************************/

#include "ogrsublayersgui.h"

#include "qgscontexthelp.h"

//qt includes

//standard includes

OGRSubLayersGui::OGRSubLayersGui( QWidget* parent, Qt::WFlags fl )

    : QDialog( parent, fl )

{

  setupUi( this );

  layersTable->setColumnCount(3);

  QStringList labels;

  labels << tr("Layer ID") << tr("Layer name") << tr("Nb of features");

  layersTable->setHorizontalHeaderLabels(labels);

  layersTable->setColumnWidth(0,188);

  layersTable->setColumnWidth(1,188);

  layersTable->setColumnWidth(2,188);

  layersTable->setShowGrid(false);

}

OGRSubLayersGui::~OGRSubLayersGui()

{

}

void OGRSubLayersGui::on_buttonBox_accepted()

{

  //close the dialog

  QStringList list=QStringList();

  for (int i = 0; i < layersTable-> selectedItems().size(); i++)

  {

    if (1 == layersTable-> selectedItems().at(i)->column())

    {

      list.append(layersTable-> selectedItems().at(i)->text() );

    }

  }

  emit updated( &list );

  accept();

}

void OGRSubLayersGui::on_buttonBox_rejected()

{

  reject();

}

void OGRSubLayersGui::populateLayerTable (QStringList *theList)

{

  for (int i =0; i< theList->size(); i++){

    QString ligne = theList -> at(i);

    QStringList elements = ligne.split(":");

    QTableWidgetItem *layerIDItem = new QTableWidgetItem(elements.at(0));

    QTableWidgetItem *layerNameItem = new QTableWidgetItem(elements.at(1));

    QTableWidgetItem *featuresItem = new QTableWidgetItem(elements.at(2));

    int row = layersTable->rowCount();

    layersTable->insertRow(row);

    layersTable->setItem(row, 0, layerIDItem);

    layersTable->setItem(row, 1, layerNameItem);

    layersTable->setItem(row, 2, featuresItem);

  }  

}

void  OGRSubLayersGui::updateSelection()

{

}

/***************************************************************************

    ogrsublayers.h

    -------------------

    begin                : Jan 21, 2004

    copyright            : (C) 2004 by Tim Sutton

    email                : [email protected]

 ***************************************************************************/

/***************************************************************************

 *                                                                         *

 *   This program is free software; you can redistribute it and/or modify  *

 *   it under the terms of the GNU General Public License as published by  *

 *   the Free Software Foundation; either version 2 of the License, or     *

 *   (at your option) any later version.                                   *

 *                                                                         *

 ***************************************************************************/

/*  $Id: plugin.h 9138 2008-08-23 21:37:31Z jef $ */

/***************************************************************************

 *   QGIS Programming conventions:

 *

 *   mVariableName - a class level member variable

 *   sVariableName - a static class level member variable

 *   variableName() - accessor for a class member (no 'get' in front of name)

 *   setVariableName() - mutator for a class member (prefix with 'set')

 *

 *   Additional useful conventions:

 *

 *   theVariableName - a method parameter (prefix with 'the')

 *   myVariableName - a locally declared variable within a method ('my' prefix)

 *

 *   DO: Use mixed case variable names - myVariableName

 *   DON'T: separate variable names using underscores: my_variable_name (NO!)

 *

 * **************************************************************************/

#ifndef OGRSubLayers_H

#define OGRSubLayers_H

//QT4 includes

#include <QObject>

//QGIS includes

#include "../qgisplugin.h"

//forward declarations

class QAction;

class QToolBar;

class QgisInterface;

/**

* \class Plugin

* \brief [name] plugin for QGIS

* [description]

*/

class OGRSubLayers: public QObject, public QgisPlugin

{

    Q_OBJECT

  public:

    //////////////////////////////////////////////////////////////////////

    //

    //                MANDATORY PLUGIN METHODS FOLLOW

    //

    //////////////////////////////////////////////////////////////////////

    /**

    * Constructor for a plugin. The QgisInterface pointer is passed by

    * QGIS when it attempts to instantiate the plugin.

    * @param theInterface Pointer to the QgisInterface object.

     */

    OGRSubLayers( QgisInterface * theInterface );

    //! Destructor

    virtual ~OGRSubLayers();

  public slots:

    //! init the gui

    virtual void initGui();

    //! Show the dialog box

    void run();

    //! unload the plugin

    void unload();

    //! show the help document

    void help();

    void load( QStringList * list);

  private:

    QString uri;

    ////////////////////////////////////////////////////////////////////

    //

    // MANDATORY PLUGIN PROPERTY DECLARATIONS  .....

    //

    ////////////////////////////////////////////////////////////////////

    int mPluginType;

    //! Pointer to the QGIS interface object

    QgisInterface *mQGisIface;

    //!pointer to the qaction for this plugin

    QAction * mQActionPointer;

    ////////////////////////////////////////////////////////////////////

    //

    // ADD YOUR OWN PROPERTY DECLARATIONS AFTER THIS POINT.....

    //

    ////////////////////////////////////////////////////////////////////

};

#endif //OGRSubLayers_H

/***************************************************************************

 *   Copyright (C) 2003 by Tim Sutton                                      *

 *   [email protected]                                                     *

 *                                                                         *

 *   This is a plugin generated from the QGIS plugin template              *

 *                                                                         *

 *   This program is free software; you can redistribute it and/or modify  *

 *   it under the terms of the GNU General Public License as published by  *

 *   the Free Software Foundation; either version 2 of the License, or     *

 *   (at your option) any later version.                                   *

 ***************************************************************************/

#ifndef OGRSubLayersGUI_H

#define OGRSubLayersGUI_H

#include <QDialog>

#include <QTableWidgetItem>

#include <ui_ogrsublayersguibase.h>

#include <qgslogger.h>

/**

@author Tim Sutton

*/

class OGRSubLayersGui : public QDialog, private Ui::OGRSubLayersGuiBase

{

    Q_OBJECT

  public:

    OGRSubLayersGui( QWidget* parent = 0, Qt::WFlags fl = 0 );

    ~OGRSubLayersGui();

    void populateLayerTable (QStringList *theList);

    QStringList * getSelection ();

    void updateSelection();

  private:

    static const int context_id = 0;

  private slots:

    void on_buttonBox_accepted();

    void on_buttonBox_rejected();

  signals:

    void updated(QStringList*list);

};

#endif

<ui version="4.0" >

 <class>OGRSubLayersGuiBase</class>

 <widget class="QDialog" name="OGRSubLayersGuiBase" >

  <property name="geometry" >

   <rect>

    <x>0</x>

    <y>0</y>

    <width>584</width>

    <height>535</height>

   </rect>

  </property>

  <property name="windowTitle" >

   <string>Select OGR layers to load</string>

  </property>

  <property name="windowIcon" >

   <iconset/>

  </property>

  <layout class="QGridLayout" >

   <property name="leftMargin" >

    <number>9</number>

   </property>

   <property name="topMargin" >

    <number>9</number>

   </property>

   <property name="rightMargin" >

    <number>9</number>

   </property>

   <property name="bottomMargin" >

    <number>9</number>

   </property>

   <property name="horizontalSpacing" >

    <number>6</number>

   </property>

   <property name="verticalSpacing" >

    <number>6</number>

   </property>

   <item row="0" column="0" >

    <widget class="QLabel" name="txtHeading" >

     <property name="sizePolicy" >

      <sizepolicy vsizetype="Minimum" hsizetype="Preferred" >

       <horstretch>0</horstretch>

       <verstretch>0</verstretch>

      </sizepolicy>

     </property>

     <property name="font" >

      <font>

       <family>Sans Serif</family>

       <pointsize>24</pointsize>

       <weight>75</weight>

       <italic>false</italic>

       <bold>true</bold>

       <underline>false</underline>

       <strikeout>false</strikeout>

      </font>

     </property>

     <property name="text" >

      <string>Sub layers list</string>

     </property>

     <property name="alignment" >

      <set>Qt::AlignCenter</set>

     </property>

    </widget>

   </item>

   <item row="6" column="0" >

    <widget class="QDialogButtonBox" name="buttonBox" >

     <property name="orientation" >

      <enum>Qt::Horizontal</enum>

     </property>

     <property name="standardButtons" >

      <set>QDialogButtonBox::Cancel|QDialogButtonBox::NoButton|QDialogButtonBox::Ok</set>

     </property>

    </widget>

   </item>

   <item row="2" column="0" >

    <widget class="QTableWidget" name="layersTable" >

     <property name="minimumSize" >

      <size>

       <width>564</width>

       <height>274</height>

      </size>

     </property>

     <property name="maximumSize" >

      <size>

       <width>564</width>

       <height>274</height>

      </size>

     </property>

     <property name="editTriggers" >

      <set>QAbstractItemView::NoEditTriggers</set>

     </property>

     <property name="selectionMode" >

      <enum>QAbstractItemView::MultiSelection</enum>

     </property>

     <property name="selectionBehavior" >

      <enum>QAbstractItemView::SelectRows</enum>

     </property>

    </widget>

   </item>

   <item row="1" column="0" >

    <widget class="QTextEdit" name="textEdit" >

     <property name="html" >

      <string>&lt;html>&lt;head>&lt;meta name="qrichtext" content="1" />&lt;style type="text/css">

p, li { white-space: pre-wrap; }

</style></head><body style=" font-family:'Sans Serif'; font-size:9pt; font-weight:400; font-style:normal;">

<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px;">This is the list of all layers available in the datasource of the active layer. You can select the layers to load. The layers will be loaded when you press "OK".</p>

<p style="-qt-paragraph-type:empty; margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px;"></p>

<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px;">The layer name is format dependant. Consult the OGR documentation or the documentation of your data format to determine the nature of the included information.</p>

<p style="-qt-paragraph-type:empty; margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px;"></p>

&lt;p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px;">&lt;span style=" font-weight:600;">Be advised: &lt;/span>selecting an already opened layer will not generate an error message and the layer will end up loaded twice!&lt;/p>&lt;/body>&lt;/html></string>

     </property>

    </widget>

   </item>

  </layout>

 </widget>

 <layoutdefault spacing="6" margin="11" />

 <resources/>

 <connections/>

</ui>

Welcome to the OGR multilayer plugin

-------------------------------------------------------------

This plugin is designed to allow you to choose the layers you

want to load from an OGR multilayer datasource like KML or S57.

-------------------------------------------------------------

The plugin usage is very simple.

Once the plugin has been loaded with the Plugins Manager, you 

will find a new icon in the toolbar.

To choose the layers to load:

First load you datasource as you always did until now. 

("V" key, or add a new vector layer menu entry, then

select the datafile from which you wish to load the data).

If everything goes well, you will see a new layer in the layer 

lists on the left side of the screen (assuming you still have

the standard screen layout...). In fact, this layer is the

layer which has an ID of 0 in OGR. This is the default layer

loader by QGis normally.

If you select this layer (which makes it the active layer) and

clic on the plugin icon, and if the datasource contains more

than just one layer, then you will be presented with the list

of all the layers that are available for you to load and display.

Select the different layers you want to load into QGis. 

Be advised: nothing prevents you from loading a layer that you

have already loaded (for exemple, il you select the first line in

the list, you will load the first layer a second time)

When you are done with the selection, you can clic OK and

the selected layers will hopefully be loaded into QGis.

You can then manage the loaded layers as you are used to do with

usual data sources. There is absolutly no difference.

Please feel free to report any bug, comment or question to

[email protected]

	   /**

     * Sub-layers handled by this provider, in order from bottom to top

     *

     * Sub-layers are used when the provider's source can combine layers

     * it knows about in some way before it hands them off to the provider.

     */

    virtual QStringList subLayers();

  protected:

    /** loads fields from input file to member attributeFields */

    void loadFields();

    /**Get an attribute associated with a feature*/

    void getFeatureAttribute( OGRFeatureH ogrFet, QgsFeature & f, int attindex );

  // This part of the code parses the uri transmitted to the ogr provider to 

  // get the options the client wants us to apply

  QString mFilePath;

  QString theLayerName;

  int theLayerIndex=0;

  // If there is no & in the uri, then the uri is just the filename. The loaded

  // layer will be layer 0.

  if ( ! uri.contains('&', Qt::CaseSensitive))

  {

    mFilePath = uri;

  }

  else

  {

  // If we get here, there are some options added to the filename. We must parse

  // the different parts separated by &, and among each option, the name and the

  // value around the =.

  // A valid uri is of the form: filename&option1=value1&option2=value2,...

 	  QStringList theURIParts = uri.split("&");

    mFilePath = theURIParts.at( 0 );

    for (int i = 1 ; i < theURIParts.size(); i++ )

    {

      QStringList theInstruction = theURIParts.at( i ).split( "=" );

      if ( 0 == theInstruction.at( 0 ).compare( QString( "layerid" )))

      {

        bool ok;

        theLayerIndex = theInstruction.at( 1 ).toInt( &ok );

        if ( ! ok )

        {

          theLayerIndex = 0;

        }

      }

      if ( 0 == theInstruction.at( 0 ).compare( QString( "layername" )))

      {

        theLayerName = theInstruction.at( 1 );

      }				

    }

  }

  QgsLogger::debug("mFilePath: " + mFilePath);

  QgsLogger::debug("theLayerIndex: "+theLayerIndex);

  QgsLogger::debug("theLayerName: "+theLayerName);

  ogrDataSource = OGROpen( QFile::encodeName( mFilePath ).constData(), TRUE, &ogrDriver );

    ogrDataSource = OGROpen( QFile::encodeName( mFilePath ).constData(), FALSE, &ogrDriver );

    // We get the layer which was requested by the uri. The layername

    // has precedence over the layerid if both are given.

    if ( NULL == theLayerName )

    {

      ogrLayer = OGR_DS_GetLayer( ogrDataSource, theLayerIndex );

    }else

    {

      ogrLayer = OGR_DS_GetLayerByName( ogrDataSource, (char*)(theLayerName.toLocal8Bit().data()) );

    }

QStringList QgsOgrProvider::subLayers()

{

  QStringList theList = QStringList();

  if (! valid )

  {

    return theList;

  }

  for ( int i = 0; i < layerCount() ; i++ )

  {  

    QString theLayerName = QString(OGR_FD_GetName(OGR_L_GetLayerDefn(OGR_DS_GetLayer( ogrDataSource, i ))));

    int theLayerFeatureCount=OGR_L_GetFeatureCount(OGR_DS_GetLayer( ogrDataSource, i ),1) ;

    theList.append(QString::number(i)+":"+ theLayerName+":"+QString::number(theLayerFeatureCount));

  }

  return theList;

}