Function applyHasAttribute

applyHasAttribute(layerId, attributeId): string
JMap.Map.Filter.applyHasAttribute

Render only layer's features that has the attribute defined in their properties. If the feature attribute is defined but its value is undefined, the feature will be rendered.

Only one attribute filter can be set for a specific layer and attributeId at the same time.
Parameters
- layerId: JId
  The JMap layer id
- attributeId: string
  The JMap attribute id
Returns string
The filter id. By example for layer 4 and attribute 'on_off' => "attribute-4-on_off"
Throws
Error if layer or attribute is not found

Example
```
// Will render only features having attribute "name" for layer 4
JMap.Map.Filter.applyHasAttribute(4, "name")
```