QGIS API Documentation  2.99.0-Master (0a63d1f)
qgsexpressionbuilderwidget.cpp
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1 /***************************************************************************
2  qgisexpressionbuilderwidget.cpp - A generic expression string builder widget.
3  --------------------------------------
4  Date : 29-May-2011
5  Copyright : (C) 2011 by Nathan Woodrow
6  Email : woodrow.nathan at gmail dot com
7  ***************************************************************************
8  * *
9  * This program is free software; you can redistribute it and/or modify *
10  * it under the terms of the GNU General Public License as published by *
11  * the Free Software Foundation; either version 2 of the License, or *
12  * (at your option) any later version. *
13  * *
14  ***************************************************************************/
15 
17 #include "qgslogger.h"
18 #include "qgsexpression.h"
19 #include "qgsmessageviewer.h"
20 #include "qgsapplication.h"
21 #include "qgspythonrunner.h"
22 #include "qgsgeometry.h"
23 #include "qgsfeature.h"
24 #include "qgsfeatureiterator.h"
25 #include "qgsvectorlayer.h"
26 
27 #include <QSettings>
28 #include <QMenu>
29 #include <QFile>
30 #include <QTextStream>
31 #include <QDir>
32 #include <QInputDialog>
33 #include <QComboBox>
34 #include <QGraphicsOpacityEffect>
35 #include <QPropertyAnimation>
36 
37 
38 
40  : QWidget( parent )
41  , mAutoSave( true )
42  , mLayer( nullptr )
43  , highlighter( nullptr )
44  , mExpressionValid( false )
45 {
46  setupUi( this );
47 
48  mValueGroupBox->hide();
49  mLoadGroupBox->hide();
50 // highlighter = new QgsExpressionHighlighter( txtExpressionString->document() );
51 
52  mModel = new QStandardItemModel();
53  mProxyModel = new QgsExpressionItemSearchProxy();
54  mProxyModel->setDynamicSortFilter( true );
55  mProxyModel->setSourceModel( mModel );
56  expressionTree->setModel( mProxyModel );
57  expressionTree->setSortingEnabled( true );
58  expressionTree->sortByColumn( 0, Qt::AscendingOrder );
59 
60  expressionTree->setContextMenuPolicy( Qt::CustomContextMenu );
61  connect( this, SIGNAL( expressionParsed( bool ) ), this, SLOT( setExpressionState( bool ) ) );
62  connect( expressionTree, SIGNAL( customContextMenuRequested( const QPoint & ) ), this, SLOT( showContextMenu( const QPoint & ) ) );
63  connect( expressionTree->selectionModel(), SIGNAL( currentChanged( const QModelIndex &, const QModelIndex & ) ),
64  this, SLOT( currentChanged( const QModelIndex &, const QModelIndex & ) ) );
65 
66  connect( btnLoadAll, SIGNAL( pressed() ), this, SLOT( loadAllValues() ) );
67  connect( btnLoadSample, SIGNAL( pressed() ), this, SLOT( loadSampleValues() ) );
68 
69  Q_FOREACH ( QPushButton* button, mOperatorsGroupBox->findChildren<QPushButton *>() )
70  {
71  connect( button, SIGNAL( pressed() ), this, SLOT( operatorButtonClicked() ) );
72  }
73 
74  txtSearchEdit->setPlaceholderText( tr( "Search" ) );
75 
76  mValuesModel = new QStringListModel();
77  mProxyValues = new QSortFilterProxyModel();
78  mProxyValues->setSourceModel( mValuesModel );
79  mValuesListView->setModel( mProxyValues );
80  txtSearchEditValues->setPlaceholderText( tr( "Search" ) );
81 
82  QSettings settings;
83  splitter->restoreState( settings.value( QStringLiteral( "/Windows/QgsExpressionBuilderWidget/splitter" ) ).toByteArray() );
84  editorSplit->restoreState( settings.value( QStringLiteral( "/Windows/QgsExpressionBuilderWidget/editorsplitter" ) ).toByteArray() );
85  functionsplit->restoreState( settings.value( QStringLiteral( "/Windows/QgsExpressionBuilderWidget/functionsplitter" ) ).toByteArray() );
86 
87  txtExpressionString->setFoldingVisible( false );
88 
89  updateFunctionTree();
90 
92  {
93  QgsPythonRunner::eval( QStringLiteral( "qgis.user.expressionspath" ), mFunctionsPath );
94  updateFunctionFileList( mFunctionsPath );
95  }
96  else
97  {
98  tab_2->hide();
99  }
100 
101  // select the first item in the function list
102  // in order to avoid a blank help widget
103  QModelIndex firstItem = mProxyModel->index( 0, 0, QModelIndex() );
104  expressionTree->setCurrentIndex( firstItem );
105 
106  lblAutoSave->setText( QLatin1String( "" ) );
107  txtExpressionString->setWrapMode( QsciScintilla::WrapWord );
108 }
109 
110 
112 {
113  QSettings settings;
114  settings.setValue( QStringLiteral( "/Windows/QgsExpressionBuilderWidget/splitter" ), splitter->saveState() );
115  settings.setValue( QStringLiteral( "/Windows/QgsExpressionBuilderWidget/editorsplitter" ), editorSplit->saveState() );
116  settings.setValue( QStringLiteral( "/Windows/QgsExpressionBuilderWidget/functionsplitter" ), functionsplit->saveState() );
117 
118  delete mModel;
119  delete mProxyModel;
120  delete mValuesModel;
121  delete mProxyValues;
122 }
123 
125 {
126  mLayer = layer;
127 
128  //TODO - remove existing layer scope from context
129 
130  if ( mLayer )
131  mExpressionContext << QgsExpressionContextUtils::layerScope( mLayer );
132 }
133 
134 void QgsExpressionBuilderWidget::currentChanged( const QModelIndex &index, const QModelIndex & )
135 {
136  txtSearchEditValues->setText( QLatin1String( "" ) );
137 
138  // Get the item
139  QModelIndex idx = mProxyModel->mapToSource( index );
140  QgsExpressionItem* item = dynamic_cast<QgsExpressionItem*>( mModel->itemFromIndex( idx ) );
141  if ( !item )
142  return;
143 
144  if ( item->getItemType() == QgsExpressionItem::Field && mFieldValues.contains( item->text() ) )
145  {
146  const QStringList& values = mFieldValues[item->text()];
147  mValuesModel->setStringList( values );
148  }
149 
150  mLoadGroupBox->setVisible( item->getItemType() == QgsExpressionItem::Field && mLayer );
151  mValueGroupBox->setVisible(( item->getItemType() == QgsExpressionItem::Field && mLayer ) || mValuesListView->model()->rowCount() > 0 );
152 
153  // Show the help for the current item.
154  QString help = loadFunctionHelp( item );
155  txtHelpText->setText( help );
156 }
157 
158 void QgsExpressionBuilderWidget::on_btnRun_pressed()
159 {
160  if ( !cmbFileNames->currentItem() )
161  return;
162 
163  QString file = cmbFileNames->currentItem()->text();
164  saveFunctionFile( file );
165  runPythonCode( txtPython->text() );
166 }
167 
168 void QgsExpressionBuilderWidget::runPythonCode( const QString& code )
169 {
170  if ( QgsPythonRunner::isValid() )
171  {
172  QString pythontext = code;
173  QgsPythonRunner::run( pythontext );
174  }
175  updateFunctionTree();
176  loadFieldNames();
177  loadRecent( mRecentKey );
178 }
179 
181 {
182  QDir myDir( mFunctionsPath );
183  if ( !myDir.exists() )
184  {
185  myDir.mkpath( mFunctionsPath );
186  }
187 
188  if ( !fileName.endsWith( QLatin1String( ".py" ) ) )
189  {
190  fileName.append( ".py" );
191  }
192 
193  fileName = mFunctionsPath + QDir::separator() + fileName;
194  QFile myFile( fileName );
195  if ( myFile.open( QIODevice::WriteOnly | QFile::Truncate ) )
196  {
197  QTextStream myFileStream( &myFile );
198  myFileStream << txtPython->text() << endl;
199  myFile.close();
200  }
201 }
202 
204 {
205  mFunctionsPath = path;
206  QDir dir( path );
207  dir.setNameFilters( QStringList() << QStringLiteral( "*.py" ) );
208  QStringList files = dir.entryList( QDir::Files );
209  cmbFileNames->clear();
210  Q_FOREACH ( const QString& name, files )
211  {
212  QFileInfo info( mFunctionsPath + QDir::separator() + name );
213  if ( info.baseName() == QLatin1String( "__init__" ) ) continue;
214  QListWidgetItem* item = new QListWidgetItem( QgsApplication::getThemeIcon( QStringLiteral( "console/iconTabEditorConsole.png" ) ), info.baseName() );
215  cmbFileNames->addItem( item );
216  }
217  if ( !cmbFileNames->currentItem() )
218  cmbFileNames->setCurrentRow( 0 );
219 }
220 
221 void QgsExpressionBuilderWidget::newFunctionFile( const QString& fileName )
222 {
223  QList<QListWidgetItem*> items = cmbFileNames->findItems( fileName, Qt::MatchExactly );
224  if ( !items.isEmpty() )
225  return;
226 
227  QString templatetxt;
228  QgsPythonRunner::eval( QStringLiteral( "qgis.user.expressions.template" ), templatetxt );
229  txtPython->setText( templatetxt );
230  cmbFileNames->insertItem( 0, fileName );
231  cmbFileNames->setCurrentRow( 0 );
232  saveFunctionFile( fileName );
233 }
234 
235 void QgsExpressionBuilderWidget::on_btnNewFile_pressed()
236 {
237  bool ok;
238  QString text = QInputDialog::getText( this, tr( "Enter new file name" ),
239  tr( "File name:" ), QLineEdit::Normal,
240  QLatin1String( "" ), &ok );
241  if ( ok && !text.isEmpty() )
242  {
243  newFunctionFile( text );
244  }
245 }
246 
247 void QgsExpressionBuilderWidget::on_cmbFileNames_currentItemChanged( QListWidgetItem* item, QListWidgetItem* lastitem )
248 {
249  if ( lastitem )
250  {
251  QString filename = lastitem->text();
252  saveFunctionFile( filename );
253  }
254  QString path = mFunctionsPath + QDir::separator() + item->text();
255  loadCodeFromFile( path );
256 }
257 
259 {
260  if ( !path.endsWith( QLatin1String( ".py" ) ) )
261  path.append( ".py" );
262 
263  txtPython->loadScript( path );
264 }
265 
267 {
268  txtPython->setText( code );
269 }
270 
271 void QgsExpressionBuilderWidget::on_expressionTree_doubleClicked( const QModelIndex &index )
272 {
273  QModelIndex idx = mProxyModel->mapToSource( index );
274  QgsExpressionItem* item = dynamic_cast<QgsExpressionItem*>( mModel->itemFromIndex( idx ) );
275  if ( !item )
276  return;
277 
278  // Don't handle the double click it we are on a header node.
279  if ( item->getItemType() == QgsExpressionItem::Header )
280  return;
281 
282  // Insert the expression text or replace selected text
283  txtExpressionString->insertText( item->getExpressionText() );
284  txtExpressionString->setFocus();
285 }
286 
288 {
289  // TODO We should really return a error the user of the widget that
290  // the there is no layer set.
291  if ( !mLayer )
292  return;
293 
294  loadFieldNames( mLayer->fields() );
295 }
296 
298 {
299  if ( fields.isEmpty() )
300  return;
301 
302  QStringList fieldNames;
303  //Q_FOREACH ( const QgsField& field, fields )
304  fieldNames.reserve( fields.count() );
305  for ( int i = 0; i < fields.count(); ++i )
306  {
307  QString fieldName = fields.at( i ).name();
308  fieldNames << fieldName;
309  registerItem( QStringLiteral( "Fields and Values" ), fieldName, " \"" + fieldName + "\" ", QLatin1String( "" ), QgsExpressionItem::Field, false, i );
310  }
311 // highlighter->addFields( fieldNames );
312 }
313 
314 void QgsExpressionBuilderWidget::loadFieldsAndValues( const QMap<QString, QStringList> &fieldValues )
315 {
316  QgsFields fields;
317  Q_FOREACH ( const QString& fieldName, fieldValues.keys() )
318  {
319  fields.append( QgsField( fieldName ) );
320  }
321  loadFieldNames( fields );
322  mFieldValues = fieldValues;
323 }
324 
325 void QgsExpressionBuilderWidget::fillFieldValues( const QString& fieldName, int countLimit )
326 {
327  // TODO We should really return a error the user of the widget that
328  // the there is no layer set.
329  if ( !mLayer )
330  return;
331 
332  // TODO We should thread this so that we don't hold the user up if the layer is massive.
333 
334  int fieldIndex = mLayer->fields().lookupField( fieldName );
335 
336  if ( fieldIndex < 0 )
337  return;
338 
339  QList<QVariant> values;
340  QStringList strValues;
341  mLayer->uniqueValues( fieldIndex, values, countLimit );
342  Q_FOREACH ( const QVariant& value, values )
343  {
344  QString strValue;
345  if ( value.isNull() )
346  strValue = QStringLiteral( "NULL" );
347  else if ( value.type() == QVariant::Int || value.type() == QVariant::Double || value.type() == QVariant::LongLong )
348  strValue = value.toString();
349  else
350  strValue = '\'' + value.toString().replace( '\'', QLatin1String( "''" ) ) + '\'';
351  strValues.append( strValue );
352  }
353  mValuesModel->setStringList( strValues );
354  mFieldValues[fieldName] = strValues;
355 }
356 
357 void QgsExpressionBuilderWidget::registerItem( const QString& group,
358  const QString& label,
359  const QString& expressionText,
360  const QString& helpText,
361  QgsExpressionItem::ItemType type, bool highlightedItem, int sortOrder )
362 {
363  QgsExpressionItem* item = new QgsExpressionItem( label, expressionText, helpText, type );
364  item->setData( label, Qt::UserRole );
365  item->setData( sortOrder, QgsExpressionItem::CUSTOM_SORT_ROLE );
366 
367  // Look up the group and insert the new function.
368  if ( mExpressionGroups.contains( group ) )
369  {
370  QgsExpressionItem *groupNode = mExpressionGroups.value( group );
371  groupNode->appendRow( item );
372  }
373  else
374  {
375  // If the group doesn't exist yet we make it first.
376  QgsExpressionItem *newgroupNode = new QgsExpressionItem( QgsExpression::group( group ), QLatin1String( "" ), QgsExpressionItem::Header );
377  newgroupNode->setData( group, Qt::UserRole );
378  //Recent group should always be last group
379  newgroupNode->setData( group.startsWith( QLatin1String( "Recent (" ) ) ? 2 : 1, QgsExpressionItem::CUSTOM_SORT_ROLE );
380  newgroupNode->appendRow( item );
381  newgroupNode->setBackground( QBrush( QColor( "#eee" ) ) );
382  mModel->appendRow( newgroupNode );
383  mExpressionGroups.insert( group, newgroupNode );
384  }
385 
386  if ( highlightedItem )
387  {
388  //insert a copy as a top level item
389  QgsExpressionItem* topLevelItem = new QgsExpressionItem( label, expressionText, helpText, type );
390  topLevelItem->setData( label, Qt::UserRole );
391  item->setData( 0, QgsExpressionItem::CUSTOM_SORT_ROLE );
392  QFont font = topLevelItem->font();
393  font.setBold( true );
394  topLevelItem->setFont( font );
395  mModel->appendRow( topLevelItem );
396  }
397 
398 }
399 
401 {
402  return mExpressionValid;
403 }
404 
405 void QgsExpressionBuilderWidget::saveToRecent( const QString& collection )
406 {
407  QSettings settings;
408  QString location = QStringLiteral( "/expressions/recent/%1" ).arg( collection );
409  QStringList expressions = settings.value( location ).toStringList();
410  expressions.removeAll( this->expressionText() );
411 
412  expressions.prepend( this->expressionText() );
413 
414  while ( expressions.count() > 20 )
415  {
416  expressions.pop_back();
417  }
418 
419  settings.setValue( location, expressions );
420  this->loadRecent( collection );
421 }
422 
423 void QgsExpressionBuilderWidget::loadRecent( const QString& collection )
424 {
425  mRecentKey = collection;
426  QString name = tr( "Recent (%1)" ).arg( collection );
427  if ( mExpressionGroups.contains( name ) )
428  {
429  QgsExpressionItem* node = mExpressionGroups.value( name );
430  node->removeRows( 0, node->rowCount() );
431  }
432 
433  QSettings settings;
434  QString location = QStringLiteral( "/expressions/recent/%1" ).arg( collection );
435  QStringList expressions = settings.value( location ).toStringList();
436  int i = 0;
437  Q_FOREACH ( const QString& expression, expressions )
438  {
439  this->registerItem( name, expression, expression, expression, QgsExpressionItem::ExpressionNode, false, i );
440  i++;
441  }
442 }
443 
444 void QgsExpressionBuilderWidget::updateFunctionTree()
445 {
446  mModel->clear();
447  mExpressionGroups.clear();
448  // TODO Can we move this stuff to QgsExpression, like the functions?
449  registerItem( QStringLiteral( "Operators" ), QStringLiteral( "+" ), QStringLiteral( " + " ) );
450  registerItem( QStringLiteral( "Operators" ), QStringLiteral( "-" ), QStringLiteral( " - " ) );
451  registerItem( QStringLiteral( "Operators" ), QStringLiteral( "*" ), QStringLiteral( " * " ) );
452  registerItem( QStringLiteral( "Operators" ), QStringLiteral( "/" ), QStringLiteral( " / " ) );
453  registerItem( QStringLiteral( "Operators" ), QStringLiteral( "%" ), QStringLiteral( " % " ) );
454  registerItem( QStringLiteral( "Operators" ), QStringLiteral( "^" ), QStringLiteral( " ^ " ) );
455  registerItem( QStringLiteral( "Operators" ), QStringLiteral( "=" ), QStringLiteral( " = " ) );
456  registerItem( QStringLiteral( "Operators" ), QStringLiteral( ">" ), QStringLiteral( " > " ) );
457  registerItem( QStringLiteral( "Operators" ), QStringLiteral( "<" ), QStringLiteral( " < " ) );
458  registerItem( QStringLiteral( "Operators" ), QStringLiteral( "<>" ), QStringLiteral( " <> " ) );
459  registerItem( QStringLiteral( "Operators" ), QStringLiteral( "<=" ), QStringLiteral( " <= " ) );
460  registerItem( QStringLiteral( "Operators" ), QStringLiteral( ">=" ), QStringLiteral( " >= " ) );
461  registerItem( QStringLiteral( "Operators" ), QStringLiteral( "||" ), QStringLiteral( " || " ) );
462  registerItem( QStringLiteral( "Operators" ), QStringLiteral( "IN" ), QStringLiteral( " IN " ) );
463  registerItem( QStringLiteral( "Operators" ), QStringLiteral( "LIKE" ), QStringLiteral( " LIKE " ) );
464  registerItem( QStringLiteral( "Operators" ), QStringLiteral( "ILIKE" ), QStringLiteral( " ILIKE " ) );
465  registerItem( QStringLiteral( "Operators" ), QStringLiteral( "IS" ), QStringLiteral( " IS " ) );
466  registerItem( QStringLiteral( "Operators" ), QStringLiteral( "OR" ), QStringLiteral( " OR " ) );
467  registerItem( QStringLiteral( "Operators" ), QStringLiteral( "AND" ), QStringLiteral( " AND " ) );
468  registerItem( QStringLiteral( "Operators" ), QStringLiteral( "NOT" ), QStringLiteral( " NOT " ) );
469 
470  QString casestring = QStringLiteral( "CASE WHEN condition THEN result END" );
471  registerItem( QStringLiteral( "Conditionals" ), QStringLiteral( "CASE" ), casestring );
472 
473  registerItem( QStringLiteral( "Fields and Values" ), QStringLiteral( "NULL" ), QStringLiteral( "NULL" ) );
474 
475  // Load the functions from the QgsExpression class
476  int count = QgsExpression::functionCount();
477  for ( int i = 0; i < count; i++ )
478  {
480  QString name = func->name();
481  if ( name.startsWith( '_' ) ) // do not display private functions
482  continue;
483  if ( func->isDeprecated() ) // don't show deprecated functions
484  continue;
485  if ( func->isContextual() )
486  {
487  //don't show contextual functions by default - it's up the the QgsExpressionContext
488  //object to provide them if supported
489  continue;
490  }
491  if ( func->params() != 0 )
492  name += '(';
493  else if ( !name.startsWith( '$' ) )
494  name += QLatin1String( "()" );
495  registerItemForAllGroups( func->groups(), func->name(), ' ' + name + ' ', func->helpText() );
496  }
497 
498  loadExpressionContext();
499 }
500 
502 {
503  mDa = da;
504 }
505 
507 {
508  return txtExpressionString->text();
509 }
510 
511 void QgsExpressionBuilderWidget::setExpressionText( const QString& expression )
512 {
513  txtExpressionString->setText( expression );
514 }
515 
517 {
518  mExpressionContext = context;
519 
520  loadExpressionContext();
521 }
522 
523 void QgsExpressionBuilderWidget::on_txtExpressionString_textChanged()
524 {
525  QString text = expressionText();
526 
527  // If the string is empty the expression will still "fail" although
528  // we don't show the user an error as it will be confusing.
529  if ( text.isEmpty() )
530  {
531  lblPreview->setText( QLatin1String( "" ) );
532  lblPreview->setStyleSheet( QLatin1String( "" ) );
533  txtExpressionString->setToolTip( QLatin1String( "" ) );
534  lblPreview->setToolTip( QLatin1String( "" ) );
535  emit expressionParsed( false );
536  return;
537  }
538 
539  QgsExpression exp( text );
540 
541  if ( mLayer )
542  {
543  // Only set calculator if we have layer, else use default.
544  exp.setGeomCalculator( &mDa );
545 
546  if ( !mExpressionContext.feature().isValid() )
547  {
548  // no feature passed yet, try to get from layer
549  QgsFeature f;
550  mLayer->getFeatures().nextFeature( f );
551  mExpressionContext.setFeature( f );
552  }
553  }
554 
555  QVariant value = exp.evaluate( &mExpressionContext );
556  if ( !exp.hasEvalError() )
557  {
558  lblPreview->setText( QgsExpression::formatPreviewString( value ) );
559  }
560 
561  if ( exp.hasParserError() || exp.hasEvalError() )
562  {
563  QString tooltip = QStringLiteral( "<b>%1:</b><br>%2" ).arg( tr( "Parser Error" ), exp.parserErrorString() );
564  if ( exp.hasEvalError() )
565  tooltip += QStringLiteral( "<br><br><b>%1:</b><br>%2" ).arg( tr( "Eval Error" ), exp.evalErrorString() );
566 
567  lblPreview->setText( tr( "Expression is invalid <a href=""more"">(more info)</a>" ) );
568  lblPreview->setStyleSheet( QStringLiteral( "color: rgba(255, 6, 10, 255);" ) );
569  txtExpressionString->setToolTip( tooltip );
570  lblPreview->setToolTip( tooltip );
571  emit expressionParsed( false );
572  return;
573  }
574  else
575  {
576  lblPreview->setStyleSheet( QLatin1String( "" ) );
577  txtExpressionString->setToolTip( QLatin1String( "" ) );
578  lblPreview->setToolTip( QLatin1String( "" ) );
579  emit expressionParsed( true );
580  }
581 }
582 
583 void QgsExpressionBuilderWidget::loadExpressionContext()
584 {
585  QStringList variableNames = mExpressionContext.filteredVariableNames();
586  Q_FOREACH ( const QString& variable, variableNames )
587  {
588  registerItem( QStringLiteral( "Variables" ), variable, " @" + variable + ' ',
589  QgsExpression::variableHelpText( variable, true, mExpressionContext.variable( variable ) ),
591  mExpressionContext.isHighlightedVariable( variable ) );
592  }
593 
594  // Load the functions from the expression context
595  QStringList contextFunctions = mExpressionContext.functionNames();
596  Q_FOREACH ( const QString& functionName, contextFunctions )
597  {
598  QgsExpression::Function* func = mExpressionContext.function( functionName );
599  QString name = func->name();
600  if ( name.startsWith( '_' ) ) // do not display private functions
601  continue;
602  if ( func->params() != 0 )
603  name += '(';
604  registerItemForAllGroups( func->groups(), func->name(), ' ' + name + ' ', func->helpText() );
605  }
606 }
607 
608 void QgsExpressionBuilderWidget::registerItemForAllGroups( const QStringList& groups, const QString& label, const QString& expressionText, const QString& helpText, QgsExpressionItem::ItemType type, bool highlightedItem, int sortOrder )
609 {
610  Q_FOREACH ( const QString& group, groups )
611  {
612  registerItem( group, label, expressionText, helpText, type, highlightedItem, sortOrder );
613  }
614 }
615 
617 {
618  QWidget::showEvent( e );
619  txtExpressionString->setFocus();
620 }
621 
622 void QgsExpressionBuilderWidget::on_txtSearchEdit_textChanged()
623 {
624  mProxyModel->setFilterWildcard( txtSearchEdit->text() );
625  if ( txtSearchEdit->text().isEmpty() )
626  {
627  expressionTree->collapseAll();
628  }
629  else
630  {
631  expressionTree->expandAll();
632  QModelIndex index = mProxyModel->index( 0, 0 );
633  if ( mProxyModel->hasChildren( index ) )
634  {
635  QModelIndex child = mProxyModel->index( 0, 0, index );
636  expressionTree->selectionModel()->setCurrentIndex( child, QItemSelectionModel::ClearAndSelect );
637  }
638  }
639 }
640 
641 void QgsExpressionBuilderWidget::on_txtSearchEditValues_textChanged()
642 {
643  mProxyValues->setFilterCaseSensitivity( Qt::CaseInsensitive );
644  mProxyValues->setFilterWildcard( txtSearchEditValues->text() );
645 }
646 
647 void QgsExpressionBuilderWidget::on_lblPreview_linkActivated( const QString& link )
648 {
649  Q_UNUSED( link );
650  QgsMessageViewer * mv = new QgsMessageViewer( this );
651  mv->setWindowTitle( tr( "More info on expression error" ) );
652  mv->setMessageAsHtml( txtExpressionString->toolTip() );
653  mv->exec();
654 }
655 
656 void QgsExpressionBuilderWidget::on_mValuesListView_doubleClicked( const QModelIndex &index )
657 {
658  // Insert the item text or replace selected text
659  txtExpressionString->insertText( ' ' + index.data( Qt::DisplayRole ).toString() + ' ' );
660  txtExpressionString->setFocus();
661 }
662 
663 void QgsExpressionBuilderWidget::operatorButtonClicked()
664 {
665  QPushButton* button = dynamic_cast<QPushButton*>( sender() );
666 
667  // Insert the button text or replace selected text
668  txtExpressionString->insertText( ' ' + button->text() + ' ' );
669  txtExpressionString->setFocus();
670 }
671 
672 void QgsExpressionBuilderWidget::showContextMenu( QPoint pt )
673 {
674  QModelIndex idx = expressionTree->indexAt( pt );
675  idx = mProxyModel->mapToSource( idx );
676  QgsExpressionItem* item = dynamic_cast<QgsExpressionItem*>( mModel->itemFromIndex( idx ) );
677  if ( !item )
678  return;
679 
680  if ( item->getItemType() == QgsExpressionItem::Field && mLayer )
681  {
682  QMenu* menu = new QMenu( this );
683  menu->addAction( tr( "Load top 10 unique values" ), this, SLOT( loadSampleValues() ) );
684  menu->addAction( tr( "Load all unique values" ), this, SLOT( loadAllValues() ) );
685  menu->popup( expressionTree->mapToGlobal( pt ) );
686  }
687 }
688 
690 {
691  QModelIndex idx = mProxyModel->mapToSource( expressionTree->currentIndex() );
692  QgsExpressionItem* item = dynamic_cast<QgsExpressionItem*>( mModel->itemFromIndex( idx ) );
693  // TODO We should really return a error the user of the widget that
694  // the there is no layer set.
695  if ( !mLayer || !item )
696  return;
697 
698  mValueGroupBox->show();
699  fillFieldValues( item->text(), 10 );
700 }
701 
703 {
704  QModelIndex idx = mProxyModel->mapToSource( expressionTree->currentIndex() );
705  QgsExpressionItem* item = dynamic_cast<QgsExpressionItem*>( mModel->itemFromIndex( idx ) );
706  // TODO We should really return a error the user of the widget that
707  // the there is no layer set.
708  if ( !mLayer || !item )
709  return;
710 
711  mValueGroupBox->show();
712  fillFieldValues( item->text(), -1 );
713 }
714 
715 void QgsExpressionBuilderWidget::on_txtPython_textChanged()
716 {
717  lblAutoSave->setText( QStringLiteral( "Saving..." ) );
718  if ( mAutoSave )
719  {
720  autosave();
721  }
722 }
723 
725 {
726  // Don't auto save if not on function editor that would be silly.
727  if ( tabWidget->currentIndex() != 1 )
728  return;
729 
730  QListWidgetItem* item = cmbFileNames->currentItem();
731  if ( !item )
732  return;
733 
734  QString file = item->text();
735  saveFunctionFile( file );
736  lblAutoSave->setText( QStringLiteral( "Saved" ) );
737  QGraphicsOpacityEffect *effect = new QGraphicsOpacityEffect();
738  lblAutoSave->setGraphicsEffect( effect );
739  QPropertyAnimation *anim = new QPropertyAnimation( effect, "opacity" );
740  anim->setDuration( 2000 );
741  anim->setStartValue( 1.0 );
742  anim->setEndValue( 0.0 );
743  anim->setEasingCurve( QEasingCurve::OutQuad );
744  anim->start( QAbstractAnimation::DeleteWhenStopped );
745 }
746 
747 void QgsExpressionBuilderWidget::setExpressionState( bool state )
748 {
749  mExpressionValid = state;
750 }
751 
752 QString QgsExpressionBuilderWidget::helpStylesheet() const
753 {
754  //start with default QGIS report style
755  QString style = QgsApplication::reportStyleSheet();
756 
757  //add some tweaks
758  style += " .functionname {color: #0a6099; font-weight: bold;} "
759  " .argument {font-family: monospace; color: #bf0c0c; font-style: italic; } "
760  " td.argument { padding-right: 10px; }";
761 
762  return style;
763 }
764 
765 QString QgsExpressionBuilderWidget::loadFunctionHelp( QgsExpressionItem* expressionItem )
766 {
767  if ( !expressionItem )
768  return QLatin1String( "" );
769 
770  QString helpContents = expressionItem->getHelpText();
771 
772  // Return the function help that is set for the function if there is one.
773  if ( helpContents.isEmpty() )
774  {
775  QString name = expressionItem->data( Qt::UserRole ).toString();
776 
777  if ( expressionItem->getItemType() == QgsExpressionItem::Field )
778  helpContents = QgsExpression::helpText( QStringLiteral( "Field" ) );
779  else
780  helpContents = QgsExpression::helpText( name );
781  }
782 
783  return "<head><style>" + helpStylesheet() + "</style></head><body>" + helpContents + "</body>";
784 }
785 
786 
787 
788 
789 
791 {
792  setFilterCaseSensitivity( Qt::CaseInsensitive );
793 }
794 
795 bool QgsExpressionItemSearchProxy::filterAcceptsRow( int source_row, const QModelIndex& source_parent ) const
796 {
797  QModelIndex index = sourceModel()->index( source_row, 0, source_parent );
798  QgsExpressionItem::ItemType itemType = QgsExpressionItem::ItemType( sourceModel()->data( index, QgsExpressionItem::ITEM_TYPE_ROLE ).toInt() );
799 
800  int count = sourceModel()->rowCount( index );
801  bool matchchild = false;
802  for ( int i = 0; i < count; ++i )
803  {
804  if ( filterAcceptsRow( i, index ) )
805  {
806  matchchild = true;
807  break;
808  }
809  }
810 
811  if ( itemType == QgsExpressionItem::Header && matchchild )
812  return true;
813 
814  if ( itemType == QgsExpressionItem::Header )
815  return false;
816 
817  return QSortFilterProxyModel::filterAcceptsRow( source_row, source_parent );
818 }
819 
820 bool QgsExpressionItemSearchProxy::lessThan( const QModelIndex& left, const QModelIndex& right ) const
821 {
822  int leftSort = sourceModel()->data( left, QgsExpressionItem::CUSTOM_SORT_ROLE ).toInt();
823  int rightSort = sourceModel()->data( right, QgsExpressionItem::CUSTOM_SORT_ROLE ).toInt();
824  if ( leftSort != rightSort )
825  return leftSort < rightSort;
826 
827  QString leftString = sourceModel()->data( left, Qt::DisplayRole ).toString();
828  QString rightString = sourceModel()->data( right, Qt::DisplayRole ).toString();
829 
830  //ignore $ prefixes when sorting
831  if ( leftString.startsWith( '$' ) )
832  leftString = leftString.mid( 1 );
833  if ( rightString.startsWith( '$' ) )
834  rightString = rightString.mid( 1 );
835 
836  return QString::localeAwareCompare( leftString, rightString ) < 0;
837 }
void uniqueValues(int index, QList< QVariant > &uniqueValues, int limit=-1) const
Calculates a list of unique values contained within an attribute in the layer.
int lookupField(const QString &fieldName) const
Look up field&#39;s index from the field name.
Definition: qgsfields.cpp:289
void registerItem(const QString &group, const QString &label, const QString &expressionText, const QString &helpText="", QgsExpressionItem::ItemType type=QgsExpressionItem::ExpressionNode, bool highlightedItem=false, int sortOrder=1)
Registers a node item for the expression builder.
bool isValid() const
Returns the validity of this feature.
Definition: qgsfeature.cpp:185
Class for parsing and evaluation of expressions (formerly called "search strings").
bool hasParserError() const
Returns true if an error occurred when parsing the input expression.
static unsigned index
void saveFunctionFile(QString fileName)
Save the current function editor text to the given file.
QStringList filteredVariableNames() const
Returns a filtered list of variables names set by all scopes in the context.
QString name
Definition: qgsfield.h:53
const QString helpText() const
The help text for the function.
static QString group(const QString &group)
Returns the translated name for a function group.
A abstract base class for defining QgsExpression functions.
void setFeature(const QgsFeature &feature)
Convenience function for setting a feature for the context.
void setGeomCalculator(const QgsDistanceArea &da)
Sets geometry calculator used in distance/area calculations.
static QIcon getThemeIcon(const QString &theName)
Helper to get a theme icon.
void loadSampleValues()
Load sample values into the sample value area.
void setLayer(QgsVectorLayer *layer)
Sets layer in order to get the fields and values.
void loadRecent(const QString &collection="generic")
Loads the recent expressions from the given collection.
QVariant evaluate()
Evaluate the feature and return the result.
QString evalErrorString() const
Returns evaluation error.
Container of fields for a vector layer.
Definition: qgsfields.h:39
bool filterAcceptsRow(int source_row, const QModelIndex &source_parent) const override
The feature class encapsulates a single feature including its id, geometry and a list of field/values...
Definition: qgsfeature.h:136
static QString formatPreviewString(const QVariant &value)
Formats an expression result for friendly display to the user.
static QString reportStyleSheet()
get a standard css style sheet for reports.
int count() const
Return number of items.
Definition: qgsfields.cpp:115
QString parserErrorString() const
Returns parser error.
void loadFunctionCode(const QString &code)
Load code into the function editor.
QVariant variable(const QString &name) const
Fetches a matching variable from the context.
void loadCodeFromFile(QString path)
Load code from the given file into the function editor.
void newFunctionFile(const QString &fileName="scratch")
Create a new file in the function editor.
QgsFields fields() const
Returns the list of fields of this layer.
QgsField at(int i) const
Get field at particular index (must be in range 0..N-1)
Definition: qgsfields.cpp:135
void updateFunctionFileList(const QString &path)
Update the list of function files found at the given path.
static const QList< Function * > & Functions()
void setMessageAsHtml(const QString &msg)
static int functionCount()
Returns the number of functions defined in the parser.
Search proxy used to filter the QgsExpressionBuilderWidget tree.
bool isHighlightedVariable(const QString &name) const
Returns true if the specified variable name is intended to be highlighted to the user.
Expression contexts are used to encapsulate the parameters around which a QgsExpression should be eva...
QgsFeatureIterator getFeatures(const QgsFeatureRequest &request=QgsFeatureRequest()) const
Query the layer for features specified in request.
QString name() const
The name of the function.
bool append(const QgsField &field, FieldOrigin origin=OriginProvider, int originIndex=-1)
Append a field. The field must have unique name, otherwise it is rejected (returns false) ...
Definition: qgsfields.cpp:59
bool isContextual() const
Returns whether the function is only available if provided by a QgsExpressionContext object...
void loadFieldNames()
Loads all the field names from the layer.
static const int ITEM_TYPE_ROLE
Item type role.
Encapsulate a field in an attribute table or data source.
Definition: qgsfield.h:45
void autosave()
Auto save the current Python function code.
void setExpressionContext(const QgsExpressionContext &context)
Sets the expression context for the widget.
static bool eval(const QString &command, QString &result)
Eval a python statement.
QgsExpressionItem::ItemType getItemType() const
Get the type of expression item, e.g., header, field, ExpressionNode.
static const int CUSTOM_SORT_ROLE
Custom sort order role.
General purpose distance and area calculator.
QgsExpression::Function * function(const QString &name) const
Fetches a matching function from the context.
An expression item that can be used in the QgsExpressionBuilderWidget tree.
void setGeomCalculator(const QgsDistanceArea *calc)
Sets the geometry calculator used for distance and area calculations in expressions.
QStringList functionNames() const
Retrieves a list of function names contained in the context.
static bool run(const QString &command, const QString &messageOnError=QString())
Execute a python statement.
QString getExpressionText() const
bool lessThan(const QModelIndex &left, const QModelIndex &right) const override
void loadFieldsAndValues(const QMap< QString, QStringList > &fieldValues)
Loads field names and values from the specified map.
A generic message view for displaying QGIS messages.
bool isEmpty() const
Check whether the container is empty.
Definition: qgsfields.cpp:110
QString expressionText()
Gets the expression string that has been set in the expression area.
static QString helpText(QString name)
Returns the help text for a specified function.
QgsFeature feature() const
Convenience function for retrieving the feature for the context, if set.
void setExpressionText(const QString &expression)
Sets the expression string for the widget.
QString getHelpText() const
Get the help text that is associated with this expression item.
static QString variableHelpText(const QString &variableName, bool showValue=true, const QVariant &value=QVariant())
Returns the help text for a specified variable.
int params() const
The number of parameters this function takes.
QgsExpressionBuilderWidget(QWidget *parent=nullptr)
Create a new expression builder widget with an optional parent.
static QgsExpressionContextScope * layerScope(const QgsMapLayer *layer)
Creates a new scope which contains variables and functions relating to a QgsMapLayer.
bool nextFeature(QgsFeature &f)
QStringList groups() const
Returns a list of the groups the function belongs to.
bool hasEvalError() const
Returns true if an error occurred when evaluating last input.
Represents a vector layer which manages a vector based data sets.
void expressionParsed(bool isValid)
Emitted when the user changes the expression in the widget.
void saveToRecent(const QString &collection="generic")
Adds the current expression to the given collection.
static bool isValid()
Returns true if the runner has an instance (and thus is able to run commands)
void loadAllValues()
Load all unique values from the set layer into the sample area.
virtual bool isDeprecated() const
Returns true if the function is deprecated and should not be presented as a valid option to users in ...