A reusable widget that can be used to build a expression string. More...

#include <qgsexpressionbuilderwidget.h>

Collaboration diagram for QgsExpressionBuilderWidget:

Public Slots
void	currentChanged (const QModelIndex &index, const QModelIndex &)
void	on_expressionTree_doubleClicked (const QModelIndex &index)
void	on_txtExpressionString_textChanged ()
void	on_txtSearchEdit_textChanged ()
void	on_lblPreview_linkActivated (QString link)
void	on_mValueListWidget_itemDoubleClicked (QListWidgetItem *item)
void	operatorButtonClicked ()
void	showContextMenu (const QPoint &)
void	loadSampleValues ()
void	loadAllValues ()
Signals
void	expressionParsed (bool isValid)
	Emited when the user changes the expression in the widget.
Public Member Functions
	QgsExpressionBuilderWidget (QWidget *parent)
	~QgsExpressionBuilderWidget ()
void	setLayer (QgsVectorLayer *layer)
	Sets layer in order to get the fields and values.
void	loadFieldNames ()
	Loads all the field names from the layer.
void	loadFieldNames (QgsFieldMap fields)
QString	expressionText ()
	Gets the expression string that has been set in the expression area.
void	setExpressionText (const QString &expression)
	Sets the expression string for the widget.
void	registerItem (QString group, QString label, QString expressionText, QString helpText="", QgsExpressionItem::ItemType type=QgsExpressionItem::ExpressionNode)
	Registers a node item for the expression builder.
bool	isExpressionValid ()
Private Slots
void	setExpressionState (bool state)
Private Member Functions
void	fillFieldValues (int fieldIndex, int countLimit)
QString	loadFunctionHelp (QgsExpressionItem *functionName)
Private Attributes
QgsVectorLayer *	mLayer
QStandardItemModel *	mModel
QgsExpressionItemSearchProxy *	mProxyModel
QMap< QString, QgsExpressionItem * >	mExpressionGroups
QgsFeature	mFeature
QgsExpressionHighlighter *	highlighter
bool	mExpressionValid

Detailed Description

A reusable widget that can be used to build a expression string.

See QgsExpressionBuilderDialog for exmaple of usage.

Definition at line 106 of file qgsexpressionbuilderwidget.h.

Constructor & Destructor Documentation

QgsExpressionBuilderWidget::QgsExpressionBuilderWidget ( QWidget * parent )

Definition at line 27 of file qgsexpressionbuilderwidget.cpp.

References QgsExpression::BuiltinFunctions(), currentChanged(), expressionParsed(), QgsExpression::functionCount(), highlighter, QgsExpression::FunctionDef::mGroup, mModel, QgsExpression::FunctionDef::mName, QgsExpression::FunctionDef::mParams, mProxyModel, operatorButtonClicked(), registerItem(), setExpressionState(), and showContextMenu().

QgsExpressionBuilderWidget::~QgsExpressionBuilderWidget ( )

Definition at line 94 of file qgsexpressionbuilderwidget.cpp.

Member Function Documentation

void QgsExpressionBuilderWidget::currentChanged	(	const QModelIndex &	index,
		const QModelIndex &
	)		`[slot]`

Definition at line 104 of file qgsexpressionbuilderwidget.cpp.

References QgsExpressionItem::Field, QgsExpressionItem::getItemType(), loadFunctionHelp(), mModel, and mProxyModel.

Referenced by QgsExpressionBuilderWidget().

void QgsExpressionBuilderWidget::expressionParsed ( bool isValid ) [signal]

Emited when the user changes the expression in the widget.

Users of this widget should connect to this signal to decide if to let the user continue.

Parameters:

isValid Is true if the expression the user has typed is valid.

Referenced by on_txtExpressionString_textChanged(), and QgsExpressionBuilderWidget().

QString QgsExpressionBuilderWidget::expressionText ( )

Gets the expression string that has been set in the expression area.

Returns:: The expression as a string.

Definition at line 223 of file qgsexpressionbuilderwidget.cpp.

void QgsExpressionBuilderWidget::fillFieldValues	(	int	fieldIndex,
		int	countLimit
	)		`[private]`

Definition at line 167 of file qgsexpressionbuilderwidget.cpp.

References mLayer, and QgsVectorLayer::uniqueValues().

Referenced by loadAllValues(), and loadSampleValues().

bool QgsExpressionBuilderWidget::isExpressionValid ( )

Definition at line 218 of file qgsexpressionbuilderwidget.cpp.

References mExpressionValid.

void QgsExpressionBuilderWidget::loadAllValues ( ) [slot]

Definition at line 357 of file qgsexpressionbuilderwidget.cpp.

References QgsVectorLayer::fieldNameIndex(), fillFieldValues(), mLayer, mModel, and mProxyModel.

Referenced by showContextMenu().

void QgsExpressionBuilderWidget::loadFieldNames ( )

Loads all the field names from the layer.

Remarks:: Should this really be public couldn't we just do this for the user?

Definition at line 141 of file qgsexpressionbuilderwidget.cpp.

References mLayer, and QgsVectorLayer::pendingFields().

void QgsExpressionBuilderWidget::loadFieldNames ( QgsFieldMap fields )

Definition at line 152 of file qgsexpressionbuilderwidget.cpp.

References QgsExpressionHighlighter::addFields(), QgsExpressionItem::Field, highlighter, QgsField::name(), and registerItem().

QString QgsExpressionBuilderWidget::loadFunctionHelp ( QgsExpressionItem * functionName ) [private]

Definition at line 376 of file qgsexpressionbuilderwidget.cpp.

References QgsExpressionItem::Field, file, QgsExpressionItem::getItemType(), QgsApplication::pkgDataPath(), and QgsApplication::reportStyleSheet().

Referenced by currentChanged().

void QgsExpressionBuilderWidget::loadSampleValues ( ) [slot]

Definition at line 343 of file qgsexpressionbuilderwidget.cpp.

References QgsVectorLayer::fieldNameIndex(), fillFieldValues(), mLayer, mModel, and mProxyModel.

Referenced by showContextMenu().

void QgsExpressionBuilderWidget::on_expressionTree_doubleClicked ( const QModelIndex & index ) [slot]

Definition at line 126 of file qgsexpressionbuilderwidget.cpp.

References QgsExpressionItem::getExpressionText(), QgsExpressionItem::getItemType(), QgsExpressionItem::Header, mModel, and mProxyModel.

void QgsExpressionBuilderWidget::on_lblPreview_linkActivated ( QString link ) [slot]

Definition at line 306 of file qgsexpressionbuilderwidget.cpp.

References QgsMessageViewer::setMessageAsHtml().

void QgsExpressionBuilderWidget::on_mValueListWidget_itemDoubleClicked ( QListWidgetItem * item ) [slot]

Definition at line 315 of file qgsexpressionbuilderwidget.cpp.

void QgsExpressionBuilderWidget::on_txtExpressionString_textChanged ( ) [slot]

Definition at line 233 of file qgsexpressionbuilderwidget.cpp.

References QgsExpression::evalErrorString(), QgsExpression::evaluate(), expressionParsed(), QgsVectorLayer::geometryType(), QgsExpression::hasEvalError(), QgsExpression::hasParserError(), QgsFeature::isValid(), mFeature, mLayer, QgsExpression::needsGeometry(), QgsVectorLayer::nextFeature(), QGis::NoGeometry, QgsExpression::parserErrorString(), QgsVectorLayer::pendingAllAttributesList(), QgsVectorLayer::pendingFields(), and QgsVectorLayer::select().

void QgsExpressionBuilderWidget::on_txtSearchEdit_textChanged ( ) [slot]

Definition at line 297 of file qgsexpressionbuilderwidget.cpp.

References mProxyModel.

void QgsExpressionBuilderWidget::operatorButtonClicked ( ) [slot]

Definition at line 320 of file qgsexpressionbuilderwidget.cpp.

Referenced by QgsExpressionBuilderWidget().

void QgsExpressionBuilderWidget::registerItem	(	QString	group,
		QString	label,
		QString	expressionText,
		QString	helpText = `""`,
		QgsExpressionItem::ItemType	type = `QgsExpressionItem::ExpressionNode`
	)

Registers a node item for the expression builder.

Parameters:

group	The group the item will be show in the tree view. If the group doesn't exsit it will be created.
label	The label that is show to the user for the item in the tree.
expressionText	The text that is inserted into the expression area when the user double clicks on the item.
helpText	The help text that the user will see when item is selected.
type	The type of the expression item.