qgsmaptoolfeatureaction.cpp

/***************************************************************************
    qgsmaptoolfeatureaction.h  -  map tool for running feature actions
    ---------------------
    begin                : January 2012
    copyright            : (C) 2012 by Giuseppe Sucameli
    email                : brush.tyler at gmail dot com
 ***************************************************************************
 *                                                                         *
 *   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 "qgsmaptoolfeatureaction.h"

#include "qgsfeature.h"
#include "qgsfield.h"
#include "qgsgeometry.h"
#include "qgslogger.h"
#include "qgsmapcanvas.h"
#include "qgsmaptopixel.h"
#include "qgsmessageviewer.h"
#include "qgsactionmanager.h"
#include "qgscoordinatereferencesystem.h"
#include "qgsvectordataprovider.h"
#include "qgsvectorlayer.h"
#include "qgsproject.h"
#include "qgsmaplayerregistry.h"
#include "qgsmaplayeractionregistry.h"
#include "qgisapp.h"

#include <QSettings>
#include <QMouseEvent>
#include <QStatusBar>

QgsMapToolFeatureAction::QgsMapToolFeatureAction( QgsMapCanvas* canvas )
    : QgsMapTool( canvas )
{
}

QgsMapToolFeatureAction::~QgsMapToolFeatureAction()
{
}

void QgsMapToolFeatureAction::canvasMoveEvent( QgsMapMouseEvent* e )
{
  Q_UNUSED( e );
}

void QgsMapToolFeatureAction::canvasPressEvent( QgsMapMouseEvent* e )
{
  Q_UNUSED( e );
}

void QgsMapToolFeatureAction::canvasReleaseEvent( QgsMapMouseEvent* e )
{
  QgsMapLayer *layer = mCanvas->currentLayer();

  if ( !layer || layer->type() != QgsMapLayer::VectorLayer )
  {
    emit messageEmitted( tr( "To run an action, you must choose an active vector layer." ), QgsMessageBar::INFO );
    return;
  }

  if ( !mCanvas->layers().contains( layer ) )
  {
    // do not run actions on hidden layers
    return;
  }

  QgsVectorLayer *vlayer = qobject_cast<QgsVectorLayer *>( layer );
  if ( vlayer->actions()->size() == 0 && QgsMapLayerActionRegistry::instance()->mapLayerActions( vlayer ).isEmpty() )
  {
    emit messageEmitted( tr( "The active vector layer has no defined actions" ), QgsMessageBar::INFO );
    return;
  }

  if ( !doAction( vlayer, e->x(), e->y() ) )
    QgisApp::instance()->statusBar()->showMessage( tr( "No features at this position found." ) );
}

void QgsMapToolFeatureAction::activate()
{
  QgsMapTool::activate();
}

void QgsMapToolFeatureAction::deactivate()
{
  QgsMapTool::deactivate();
}

bool QgsMapToolFeatureAction::doAction( QgsVectorLayer *layer, int x, int y )
{
  if ( !layer )
    return false;

  QgsPoint point = mCanvas->getCoordinateTransform()->toMapCoordinates( x, y );

  QgsFeatureList featList;

  // toLayerCoordinates will throw an exception for an 'invalid' point.
  // For example, if you project a world map onto a globe using EPSG 2163
  // and then click somewhere off the globe, an exception will be thrown.
  try
  {
    // create the search rectangle
    double searchRadius = searchRadiusMU( mCanvas );

    QgsRectangle r;
    r.setXMinimum( point.x() - searchRadius );
    r.setXMaximum( point.x() + searchRadius );
    r.setYMinimum( point.y() - searchRadius );
    r.setYMaximum( point.y() + searchRadius );

    r = toLayerCoordinates( layer, r );

    QgsFeatureIterator fit = layer->getFeatures( QgsFeatureRequest().setFilterRect( r ).setFlags( QgsFeatureRequest::ExactIntersect ) );
    QgsFeature f;
    while ( fit.nextFeature( f ) )
      featList << QgsFeature( f );
  }
  catch ( QgsCsException & cse )
  {
    Q_UNUSED( cse );
    // catch exception for 'invalid' point and proceed with no features found
    QgsDebugMsg( QString( "Caught CRS exception %1" ).arg( cse.what() ) );
  }

  if ( featList.isEmpty() )
    return false;

  Q_FOREACH ( const QgsFeature& feat, featList )
  {
    if ( layer->actions()->defaultAction() >= 0 )
    {
      // define custom substitutions: layer id and clicked coords

      // TODO QGIS 3.0 - remove these deprecated global expression variables!
      QMap<QString, QVariant> substitutionMap;
      substitutionMap.insert( "$layerid", layer->id() );
      point = toLayerCoordinates( layer, point );
      substitutionMap.insert( "$clickx", point.x() );
      substitutionMap.insert( "$clicky", point.y() );

      QgsExpressionContext context;
      context << QgsExpressionContextUtils::globalScope()
      << QgsExpressionContextUtils::projectScope()
      << QgsExpressionContextUtils::mapSettingsScope( mCanvas->mapSettings() );
      QgsExpressionContextScope* actionScope = new QgsExpressionContextScope();
      actionScope->addVariable( QgsExpressionContextScope::StaticVariable( QString( "click_x" ), point.x(), true ) );
      actionScope->addVariable( QgsExpressionContextScope::StaticVariable( QString( "click_y" ), point.y(), true ) );
      context << actionScope;

      int actionIdx = layer->actions()->defaultAction();
      layer->actions()->doAction( actionIdx, feat, context, &substitutionMap );
    }
    else
    {
      QgsMapLayerAction* mapLayerAction = QgsMapLayerActionRegistry::instance()->defaultActionForLayer( layer );
      if ( mapLayerAction )
      {
        mapLayerAction->triggerForFeature( layer, &feat );
      }
    }
  }

  return true;
}