This class was introduced in Esri::ArcGISRuntime 100.0.
|DictionaryRenderer(Esri::ArcGISRuntime::DictionarySymbolStyle *dictionarySymbolStyle, const QMap<QString, QString> &symbologyFieldOverrides, const QMap<QString, QString> &textFieldOverrides, QObject *parent = nullptr)|
|DictionaryRenderer(Esri::ArcGISRuntime::DictionarySymbolStyle *dictionarySymbolStyle, QObject *parent = nullptr)|
|Esri::ArcGISRuntime::DictionarySymbolStyle *||dictionarySymbolStyle() const|
|Esri::ArcGISRuntime::ArcadeExpression *||scaleExpression() const|
|QMap<QString, QString>||symbologyFieldOverrides() const|
|QMap<QString, QString>||textFieldOverrides() const|
The DictionaryRenderer uses attributes from source data (such as fields of features in a feature table or attributes of graphics in a graphics overlay) to display unique multilayer symbols based on those attributes. This is achieved through an associated DictionarySymbolStyle.
The DictionarySymbolStyle is created using a given specification such as "mil2525d". Each specification depends on attribute names that define the symbology and text of each feature. For example, the mil2525d specification looks for attributes named "identity", "symbolset", "symbolentity", and "modifier1", among many others. These attributes reference different symbols in the style file that are assembled to create a unique symbol. In order to display features using the DictionaryRenderer, you must make sure the DictionaryRenderer and associated DictionarySymbolStyle know which attributes in your data to use. This can be achieved in multiple ways:
- Pre-author your data so that the attribute names match the attributes needed by the specification. In the case of the mil2525d specification, author a feature service (or other data source) with a field named "identity", another named "symbolset", and so on. In this scenario, you create a FeatureTable from the source data, create a FeatureLayer from the FeatureTable, apply the DictionaryRenderer to the FeatureLayer, and the symbols are generated automatically and applied to the layer in the map. The same workflow applies for Graphics in a GraphicsOverlay. Ideally when creating graphics on the fly, you can give the attributes names that match the specification. When fields in the FeatureTable and attributes in Graphics have expected names, the DictionaryRenderer automatically finds them.
- Manually map your attribute names to those expected by the specification. You can map as many attribute names as necessary for the specification, but only need to map attribute names that do not match the specification (all matching attribute names will be automatically matched by the renderer). For example, an expected attribute "symbolset" might appear as the "symbol_set" field in your FeatureTable. In this scenario, you can create a ServiceFeatureTable from a feature service, create a FeatureLayer from that feature table, create a DictionaryRenderer by manually mapping the "symbol_set" name to the "symbolset" name expected by the specification, and finally apply the renderer to the FeatureLayer.
A DictionaryRenderer can be applied to pre-authored data, such as feature services, mobile geodatabases (generated from ArcMap or a sync-enabled feature service), and feature layers in a mobile map package. You can also apply it to a GraphicsOverlay, which allow for on-the-fly graphic generation.
Note: For mil2525d, symbolset, entity, and identity fields are required to create a symbol. This information, along with the range of valid inputs can be found on the Military Features Data GitHub page.
Apply a DictionaryRenderer to a FeatureLayer:
// Create a layer and set the feature table FeatureLayer* layer = new FeatureLayer(table, this); // Create a dictionary renderer and apply to the layer DictionaryRenderer* renderer = new DictionaryRenderer(dictionarySymbolStyle, this); layer->setRenderer(renderer);
Note: For details on the currently support military standards, please see the DictionarySymbolStyle API reference.
Member Function Documentation
Renderer: : Dictionary Renderer(Esri: : *dictionary A r c GISRuntime: : Dictionary Symbol Style Symbol, const QMap<QString, QString> &symbology Style Field, const QMap<QString, QString> &text Overrides Field, QObject *parent = nullptr) Overrides
Constructor that takes a dictionarySymbolStyle, symbologyFieldOverrides, and textFieldOverrides, with an optional parent.
Use this constructor in the case where your source data's field names do not match what the DictionarySymbolStyle specification expects. The symbologyFieldOverrides and textFieldOverrides should be used to map your field names to the specification's, where the key is the specification name (e.g. "symbolset"), and the value is your field's name (e.g. "symbol_set").
Renderer: : Dictionary Renderer(Esri: : *dictionary A r c GISRuntime: : Dictionary Symbol Style Symbol, QObject *parent = nullptr) Style
Constructor that takes a dictionarySymbolStyle, with an optional parent.
: *Dictionary A r c GISRuntime: : Dictionary Symbol Style Renderer: : dictionary Symbol() const Style
: *Dictionary A r c GISRuntime: : Arcade Expression Renderer: : scale Expression() const
Returns an arcade expression object with an expression for scaling symbols in a dictionary renderer.
ArcadeExpression is evaluated at rendering time. If the expression is not valid or results in an invalid value, symbols will not be scaled and will display at their original size. For example, to scale symbols based on attribute value, ArcadeExpression object's expression property can be set to something like
iif($feature.Symbol_Set == 40, 2.5, 1)
This scales the symbol size 2.5 times when
This function was introduced in Esri::ArcGISRuntime 100.11.
See also setScaleExpression().
Renderer: : set Scale(Esri: Expression : *scale A r c GISRuntime: : Arcade Expression Expression)
Sets the scaleExpression to scaleExpression.
This function was introduced in Esri::ArcGISRuntime 100.11.
See also scaleExpression.
Returns the map of a symbology attribute and its override used to fetch a symbol from the dictionary symbol style.
In the case where your source data's field names do not match what the DictionarySymbolStyle specification expects, the proper constructor must be used to map your field names to the specification's, where the key is the specification name (e.g. "symbolset"), and the value is your field's name (e.g. "symbol_set"). This function returns the map that was set in the constructor.
Returns the map of text field overrides set in the constructor.
A DictionarySymbolStyle uses a collection of expected attribute names to build a symbol based on input values. When initialized, fields in the input dataset are mapped to the expected attribute names using case-insensitive matching. In cases where your source data's field names do not match the DictionarySymbolStyle specification, the proper constructor must be used to map your field names to the specification's. The key is the specification attribute name (e.g. "symbolset"), and the value is your attribute name (e.g. "symbol_set"). You can also exclude an expected field by providing an empty string for it in the overrides.
To obtain the valid symbology fields in a symbol dictionary, use DictionarySymbolStyle::symbologyFieldNames.