/************************************************************************
 * This file has been generated automatically from                      *
 *                                                                      *
 * src/gui/qgsfieldexpressionwidget.h                                   *
 *                                                                      *
 * Do not edit manually ! Edit header and run scripts/sipify.py again   *
 ************************************************************************/







class QgsFieldExpressionWidget : QWidget
{
%Docstring(signature="appended")
The :py:class:`QgsFieldExpressionWidget` class creates a widget to
choose fields and edit expressions It contains a combo box to display
the fields and expression and a button to open the expression dialog.
The combo box is editable, allowing expressions to be edited inline. The
validity of the expression is checked live on key press, invalid
expressions are displayed in red. The expression will be added to the
model (and the fieldChanged signals emitted) only when editing in the
line edit is finished (focus lost, enter key pressed).
%End

%TypeHeaderCode
#include "qgsfieldexpressionwidget.h"
%End
  public:
    explicit QgsFieldExpressionWidget( QWidget *parent /TransferThis/ = 0 );
%Docstring
QgsFieldExpressionWidget creates a widget with a combo box to display
the fields and expression and a button to open the expression dialog
%End

    void setExpressionDialogTitle( const QString &title );
%Docstring
define the title used in the expression dialog
%End

    void appendScope( QgsExpressionContextScope *scope /Transfer/ );
%Docstring
Appends a scope to the current expression context.

:param scope: The scope to add.

.. versionadded:: 3.2
%End

    const QString expressionDialogTitle();
%Docstring
Returns the title used for the expression dialog
%End

    void setFilters( QgsFieldProxyModel::Filters filters );
%Docstring
setFilters allows filtering according to the type of field
%End

    void setAllowEmptyFieldName( bool allowEmpty );
%Docstring
Sets whether an optional empty field ("not set") option is shown in the
combo box.

.. seealso:: :py:func:`allowEmptyFieldName`

.. versionadded:: 3.4.6
%End

    bool allowEmptyFieldName() const;
%Docstring
Returns ``True`` if the combo box allows the empty field ("not set")
choice.

.. seealso:: :py:func:`setAllowEmptyFieldName`

.. versionadded:: 3.4.6
%End

    void setLeftHandButtonStyle( bool isLeft );

    QgsFieldProxyModel::Filters filters() const;
%Docstring
currently used filter on list of fields
%End

    void setGeomCalculator( const QgsDistanceArea &da );
%Docstring
Sets the geometry calculator used in the expression dialog
%End

    QString currentField( bool *isExpression = 0, bool *isValid = 0 ) const;
%Docstring
currentField returns the currently selected field or expression if
allowed

:param isExpression: determines if the string returned is the name of a
                     field or an expression
:param isValid: determines if the expression (or field) returned is
                valid
%End

    bool isValidExpression( QString *expressionError = 0 ) const;
%Docstring
Returns ``True`` if the current expression is valid
%End

    bool isExpression() const;
%Docstring
If the content is not just a simple field this method will return
``True``.
%End

    QString currentText() const;
%Docstring
Returns the current text that is set in the expression area
%End

    QString asExpression() const;
%Docstring
Returns the currently selected field or expression. If a field is
currently selected, the returned value will be converted to a valid
expression referencing this field (ie enclosing the field name with
appropriate quotations).
%End

    QString expression() const;
%Docstring
Returns the currently selected field or expression. If a field is
currently selected, the returned value will be converted to a valid
expression referencing this field (ie enclosing the field name with
appropriate quotations).

Alias for :py:func:`~QgsFieldExpressionWidget.asExpression`
%End

    QgsVectorLayer *layer() const;
%Docstring
Returns the layer currently associated with the widget.

.. seealso:: :py:func:`setLayer`
%End

    void registerExpressionContextGenerator( const QgsExpressionContextGenerator *generator );
%Docstring
Register an expression context generator class that will be used to
retrieve an expression context for the widget.

:param generator: A :py:class:`QgsExpressionContextGenerator` class that
                  will be used to create an expression context when
                  required.
%End


    void setCustomPreviewGenerator( const QString &label, const QList<QPair<QString, QVariant>> &choices, SIP_PYCALLABLE );
%Docstring
Sets the widget to run using a custom preview generator.

In this mode, the widget will call a callback function to generate a new
:py:class:`QgsExpressionContext` as the previewed object changes. This
can be used to provide custom preview values for different objects (i.e.
for objects which aren't vector layer features).

:param label: The label to display for the combo box presenting choices
              of objects. This should be a representative name, eg
              "Band" if the widget is showing choices of raster layer
              bands
:param choices: A list of choices to present to the user. Each choice is
                a pair of a human-readable label and a QVariant
                representing the object to preview.
:param previewContextGenerator: A function which takes a QVariant
                                representing the object to preview, and
                                returns a
                                :py:class:`QgsExpressionContext` to use
                                for previewing the object.

.. versionadded:: 3.38
%End
%MethodCode
    Py_XINCREF( a2 );
    Py_BEGIN_ALLOW_THREADS
      sipCpp->setCustomPreviewGenerator( *a0, *a1, [a2]( const QVariant &value ) -> QgsExpressionContext {
        QgsExpressionContext res;
        SIP_BLOCK_THREADS
        PyObject *s = sipCallMethod( NULL, a2, "D", &value, sipType_QVariant, NULL );
        int state;
        int sipIsError = 0;
        QgsExpressionContext *t1 = reinterpret_cast<QgsExpressionContext *>( sipConvertToType( s, sipType_QgsExpressionContext, 0, SIP_NOT_NONE, &state, &sipIsError ) );
        if ( sipIsError == 0 )
        {
          res = QgsExpressionContext( *t1 );
        }
        sipReleaseType( t1, sipType_QgsExpressionContext, state );
        SIP_UNBLOCK_THREADS
        return res;
      } );

    Py_END_ALLOW_THREADS
%End

    bool allowEvalErrors() const;
%Docstring
Allow accepting expressions with evaluation errors. This can be useful
when we are not able to provide an expression context of which we are
sure it's completely populated.
%End

    void setAllowEvalErrors( bool allowEvalErrors );
%Docstring
Allow accepting expressions with evaluation errors. This can be useful
when we are not able to provide an expression context of which we are
sure it's completely populated.
%End

    bool buttonVisible() const;
%Docstring
Returns the visibility of the button

If button is hidden, the widget essentially becomes an editable combo
box

.. versionadded:: 3.36
%End

    void setButtonVisible( bool visible );
%Docstring
Set the visibility of the button

If button is hidden, the widget essentially becomes an editable combo
box

.. versionadded:: 3.36
%End

  signals:
    void fieldChanged( const QString &fieldName );
%Docstring
Emitted when the currently selected field changes.
%End

    void fieldChanged( const QString &fieldName, bool isValid );
%Docstring
fieldChanged signal with indication of the validity of the expression
%End

    void allowEvalErrorsChanged();
%Docstring
Allow accepting expressions with evaluation errors. This can be useful
when we are not able to provide an expression context of which we are
sure it's completely populated.
%End

    void buttonVisibleChanged();
%Docstring
Emitted when the button visibility changes

.. versionadded:: 3.36
%End

  public slots:

    void setLayer( QgsMapLayer *layer );
%Docstring
Sets the layer used to display the fields and expression.

.. seealso:: :py:func:`layer`
%End

    void setRow( int row );
%Docstring
sets the current row in the widget
%End

    void setField( const QString &fieldName );
%Docstring
sets the current field or expression in the widget
%End

    void setFields( const QgsFields &fields );
%Docstring
Sets the fields used in the widget to ``fields``, this allows the widget
to work without a layer.

.. versionadded:: 3.14
%End

    void setExpression( const QString &expression );
%Docstring
Sets the current expression text and if applicable also the field. Alias
for setField.
%End

  protected slots:
    void editExpression();
%Docstring
open the expression dialog to edit the current or add a new expression
%End

    void expressionEdited( const QString &expression );
%Docstring
when expression is edited by the user in the line edit, it will be
checked for validity
%End

    void expressionEditingFinished();
%Docstring
when expression has been edited (finished) it will be added to the model
%End

    void currentFieldChanged();

    void updateLineEditStyle( const QString &expression = QString() );
%Docstring
updateLineEditStyle will re-style (color/font) the line edit depending
on content and status

:param expression: if expression is given it will be evaluated for the
                   given string, otherwise it takes current expression
                   from the model
%End

    bool isExpressionValid( const QString &expressionStr );

  protected:
    virtual void changeEvent( QEvent *event );


    virtual bool eventFilter( QObject *watched, QEvent *event );


};

/************************************************************************
 * This file has been generated automatically from                      *
 *                                                                      *
 * src/gui/qgsfieldexpressionwidget.h                                   *
 *                                                                      *
 * Do not edit manually ! Edit header and run scripts/sipify.py again   *
 ************************************************************************/