Container of fields for a vector layer. More...

#include <qgsfield.h>

Classes
struct	Field

Public Types
typedef struct QgsFields::Field	Field

enum	FieldOrigin { OriginUnknown, OriginProvider, OriginJoin, OriginEdit, OriginExpression }

Public Member Functions
	QgsFields ()
	Constructor for an empty field container. More...

	QgsFields (const QgsFields &other)
	Copy constructor. More...

virtual	~QgsFields ()

QgsAttributeList	allAttributesList () const
	Utility function to get list of attribute indexes. More...

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) More...

bool	appendExpressionField (const QgsField &field, int originIndex)
	Append an expression field. The field must have unique name, otherwise it is rejected (returns false) More...

const QgsField &	at (int i) const
	Get field at particular index (must be in range 0..N-1) More...

const_iterator	begin () const noexcept
	Returns a const STL-style iterator pointing to the first item in the list. More...

iterator	begin ()
	Returns an STL-style iterator pointing to the first item in the list. More...

void	clear ()
	Remove all fields. More...

const_iterator	constBegin () const noexcept
	Returns a const STL-style iterator pointing to the first item in the list. More...

const_iterator	constEnd () const noexcept
	Returns a const STL-style iterator pointing to the imaginary item after the last item in the list. More...

int	count () const
	Return number of items. More...

const_iterator	end () const noexcept
	Returns a const STL-style iterator pointing to the imaginary item after the last item in the list. More...

iterator	end ()
	Returns an STL-style iterator pointing to the imaginary item after the last item in the list. More...

bool	exists (int i) const
	Return if a field index is valid. More...

void	extend (const QgsFields &other)
	Extend with fields from another QgsFields container. More...

const QgsField &	field (int fieldIdx) const
	Get field at particular index (must be in range 0..N-1) More...

const QgsField &	field (const QString &name) const
	Get field at particular index (must be in range 0..N-1) More...

int	fieldNameIndex (const QString &fieldName) const
	Look up field's index from name also looks up case-insensitive if there is no match otherwise. More...

FieldOrigin	fieldOrigin (int fieldIdx) const
	Get field's origin (value from an enumeration) More...

int	fieldOriginIndex (int fieldIdx) const
	Get field's origin index (its meaning is specific to each type of origin) More...

QIcon	iconForField (int fieldIdx) const
	Returns an icon corresponding to a field index, based on the field's type and source. More...

int	indexFromName (const QString &name) const
	Look up field's index from name. Returns -1 on error. More...

bool	isEmpty () const
	Check whether the container is empty. More...

	operator QVariant () const
	Allows direct construction of QVariants from fields. More...

bool	operator!= (const QgsFields &other) const

QgsFields &	operator= (const QgsFields &other)
	Assignment operator. More...

bool	operator== (const QgsFields &other) const

const QgsField &	operator[] (int i) const
	Get field at particular index (must be in range 0..N-1) More...

QgsField &	operator[] (int i)
	Get field at particular index (must be in range 0..N-1) More...

void	remove (int fieldIdx)
	Remove a field with the given index. More...

int	size () const
	Return number of items. More...

QList< QgsField >	toList () const
	Utility function to return a list of QgsField instances. More...

Detailed Description

Container of fields for a vector layer.

In addition to storing a list of QgsField instances, it also:

allows quick lookups of field names to index in the list
keeps track of where the field definition comes from (vector data provider, joined layer or newly added from an editing operation)
Note
QgsFields objects are implicitly shared.

Definition at line 252 of file qgsfield.h.

Member Typedef Documentation

◆ Field

typedef struct QgsFields::Field QgsFields::Field

Member Enumeration Documentation

◆ FieldOrigin

enum QgsFields::FieldOrigin

Enumerator
OriginUnknown	it has not been specified where the field comes from
OriginProvider	field comes from the underlying data provider of the vector layer (originIndex = index in provider's fields)
OriginJoin	field comes from a joined layer (originIndex / 1000 = index of the join, originIndex % 1000 = index within the join)
OriginEdit	field has been temporarily added in editing mode (originIndex = index in the list of added attributes)
OriginExpression	field is calculated from an expression

Definition at line 256 of file qgsfield.h.

Constructor & Destructor Documentation

◆ QgsFields() [1/2]

QgsFields::QgsFields ( )

Constructor for an empty field container.

Definition at line 313 of file qgsfield.cpp.

◆ QgsFields() [2/2]

QgsFields::QgsFields ( const QgsFields & other )

Copy constructor.

Definition at line 318 of file qgsfield.cpp.

◆ ~QgsFields()

QgsFields::~QgsFields ( )

virtual

Definition at line 329 of file qgsfield.cpp.

Member Function Documentation

◆ allAttributesList()

QgsAttributeList QgsFields::allAttributesList ( ) const

Utility function to get list of attribute indexes.

Note: added in 2.4

Definition at line 588 of file qgsfield.cpp.

◆ append()

bool QgsFields::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 at line 346 of file qgsfield.cpp.

◆ appendExpressionField()

bool QgsFields::appendExpressionField	(	const QgsField &	field,
		int	originIndex
	)

Append an expression field. The field must have unique name, otherwise it is rejected (returns false)

Definition at line 359 of file qgsfield.cpp.

◆ at()

const QgsField & QgsFields::at ( int i ) const

Get field at particular index (must be in range 0..N-1)

Definition at line 422 of file qgsfield.cpp.

◆ begin() [1/2]

QgsFields::const_iterator QgsFields::begin ( ) const

noexcept

Returns a const STL-style iterator pointing to the first item in the list.

Note: added in 2.16; not available in Python bindings

Definition at line 495 of file qgsfield.cpp.

◆ begin() [2/2]

QgsFields::iterator QgsFields::begin ( )

Returns an STL-style iterator pointing to the first item in the list.

Note: added in 2.16; not available in Python bindings

Definition at line 511 of file qgsfield.cpp.

◆ clear()

void QgsFields::clear ( )

Remove all fields.

Definition at line 334 of file qgsfield.cpp.

◆ constBegin()

QgsFields::const_iterator QgsFields::constBegin ( ) const

noexcept

Returns a const STL-style iterator pointing to the first item in the list.

Note: added in 2.16; not available in Python bindings

Definition at line 479 of file qgsfield.cpp.

◆ constEnd()

QgsFields::const_iterator QgsFields::constEnd ( ) const

noexcept

Returns a const STL-style iterator pointing to the imaginary item after the last item in the list.

Note: added in 2.16; not available in Python bindings

Definition at line 487 of file qgsfield.cpp.

◆ count()

int QgsFields::count ( ) const

Return number of items.

Definition at line 402 of file qgsfield.cpp.

◆ end() [1/2]

QgsFields::const_iterator QgsFields::end ( ) const

noexcept

Returns a const STL-style iterator pointing to the imaginary item after the last item in the list.

Note: added in 2.16; not available in Python bindings

Definition at line 503 of file qgsfield.cpp.

◆ end() [2/2]

QgsFields::iterator QgsFields::end ( )

Returns an STL-style iterator pointing to the imaginary item after the last item in the list.

Note: added in 2.16; not available in Python bindings

Definition at line 520 of file qgsfield.cpp.

◆ exists()

bool QgsFields::exists ( int i ) const

Return if a field index is valid.

Parameters

i	Index of the field which needs to be checked

Returns: True if the field exists

Definition at line 412 of file qgsfield.cpp.

◆ extend()

void QgsFields::extend ( const QgsFields & other )

Extend with fields from another QgsFields container.

Definition at line 383 of file qgsfield.cpp.

◆ field() [1/2]

const QgsField & QgsFields::field ( int fieldIdx ) const

Get field at particular index (must be in range 0..N-1)

Definition at line 427 of file qgsfield.cpp.

◆ field() [2/2]

const QgsField & QgsFields::field ( const QString & name ) const

Get field at particular index (must be in range 0..N-1)

Definition at line 432 of file qgsfield.cpp.

◆ fieldNameIndex()

int QgsFields::fieldNameIndex ( const QString & fieldName ) const

Look up field's index from name also looks up case-insensitive if there is no match otherwise.

Note: added in 2.4

Definition at line 571 of file qgsfield.cpp.

◆ fieldOrigin()

QgsFields::FieldOrigin QgsFields::fieldOrigin ( int fieldIdx ) const

Get field's origin (value from an enumeration)

Definition at line 448 of file qgsfield.cpp.

◆ fieldOriginIndex()

int QgsFields::fieldOriginIndex ( int fieldIdx ) const

Get field's origin index (its meaning is specific to each type of origin)

Definition at line 456 of file qgsfield.cpp.

◆ iconForField()

QIcon QgsFields::iconForField ( int fieldIdx ) const

Returns an icon corresponding to a field index, based on the field's type and source.

Note: added in QGIS 2.14

Definition at line 529 of file qgsfield.cpp.

◆ indexFromName()

int QgsFields::indexFromName ( const QString & name ) const

Look up field's index from name. Returns -1 on error.

Definition at line 461 of file qgsfield.cpp.

◆ isEmpty()

bool QgsFields::isEmpty ( ) const

Check whether the container is empty.

Definition at line 397 of file qgsfield.cpp.

◆ operator QVariant()

QgsFields::operator QVariant ( ) const

inline

Allows direct construction of QVariants from fields.

Definition at line 357 of file qgsfield.h.

◆ operator!=()

bool QgsFields::operator!= ( const QgsFields & other ) const

inline

Note: added in 2.6

Definition at line 350 of file qgsfield.h.

◆ operator=()

QgsFields & QgsFields::operator= ( const QgsFields & other )

Assignment operator.

Definition at line 323 of file qgsfield.cpp.

◆ operator==()

bool QgsFields::operator== ( const QgsFields & other ) const

Note: added in 2.6

Definition at line 474 of file qgsfield.cpp.

◆ operator[]() [1/2]

const QgsField & QgsFields::operator[] ( int i ) const

Get field at particular index (must be in range 0..N-1)

Definition at line 443 of file qgsfield.cpp.

◆ operator[]() [2/2]

QgsField & QgsFields::operator[] ( int i )

Get field at particular index (must be in range 0..N-1)

Definition at line 417 of file qgsfield.cpp.

◆ remove()

void QgsFields::remove ( int fieldIdx )

Remove a field with the given index.

Definition at line 370 of file qgsfield.cpp.

◆ size()

int QgsFields::size ( ) const

Return number of items.

Definition at line 407 of file qgsfield.cpp.

◆ toList()

QList< QgsField > QgsFields::toList ( ) const

Utility function to return a list of QgsField instances.

Definition at line 466 of file qgsfield.cpp.

The documentation for this class was generated from the following files:

/tmp/buildd/qgis-2.18.21+99unstable/src/core/qgsfield.h
/tmp/buildd/qgis-2.18.21+99unstable/src/core/qgsfield.cpp

Classes

Public Types

Public Member Functions

Detailed Description

Member Typedef Documentation

◆ Field

Member Enumeration Documentation

◆ FieldOrigin

Constructor & Destructor Documentation

◆ QgsFields() [1/2]

◆ QgsFields() [2/2]

◆ ~QgsFields()

Member Function Documentation

◆ allAttributesList()

◆ append()

◆ appendExpressionField()

◆ at()

◆ begin() [1/2]

◆ begin() [2/2]

◆ clear()

◆ constBegin()

◆ constEnd()

◆ count()

◆ end() [1/2]

◆ end() [2/2]

◆ exists()

◆ extend()

◆ field() [1/2]

◆ field() [2/2]

◆ fieldNameIndex()

◆ fieldOrigin()

◆ fieldOriginIndex()

◆ iconForField()

◆ indexFromName()

◆ isEmpty()

◆ operator QVariant()

◆ operator!=()

◆ operator=()

◆ operator==()

◆ operator[]() [1/2]

◆ operator[]() [2/2]

◆ remove()

◆ size()

◆ toList()