Abstract base class for the different types of expressions that can be used to create label text. More...
| Header: | #include <LabelExpression.h> |
| Since: | Esri::ArcGISRuntime 100.11 |
| Inherits: | Esri::ArcGISRuntime::Object |
| Inherited By: | Esri::ArcGISRuntime::ArcadeLabelExpression, Esri::ArcGISRuntime::SimpleLabelExpression, and Esri::ArcGISRuntime::WebmapLabelExpression |
Public Functions
| virtual | ~LabelExpression() override |
| Esri::ArcGISRuntime::LabelExpression * | clone(QObject *parent = nullptr) const |
| QString | expression() const |
| Esri::ArcGISRuntime::LabelExpressionType | labelExpressionType() const |
| void | setExpression(const QString &expression) |
Detailed Description
Users can read the expression script using the expression property. To specify an expression script, users create an object of type ArcadeLabelExpression, SimpleLabelExpression or WebmapLabelExpression with the required expression script and assign it to the label expression object.
Member Function Documentation
[override virtual] LabelExpression::~LabelExpression ()
Destructor.
[since Esri::ArcGISRuntime 200.1] Esri::ArcGISRuntime::LabelExpression *LabelExpression::clone(QObject *parent = nullptr) const
Clones the LabelExpression to a new instance with an optional parent.
Returns a new instance of the current LabelExpression.
This function was introduced in Esri::ArcGISRuntime 200.1.
QString LabelExpression::expression() const
Returns the label expression script string.
The expression is expected to be a complete, self-contained label expression in the language specified by the label expression subclass object.
Note: If the expression attempts to use attributes which don't exist then no label will be produced. This is distinct from the attribute existing but having an empty value, which can form part of the produced text label.
See also setExpression().
Esri::ArcGISRuntime::LabelExpressionType LabelExpression::labelExpressionType () const
Returns the type of the label expression.
The type specifies which language interpreter should be used to read and evaluate the expression. The object type is determined by which concrete subclass has been set into the label expression property.
See also LabelExpressionType.
void LabelExpression::setExpression (const QString &expression)
Sets the expression to expression.
See also expression.