Function getLayerIds

getLayerIds(): JId[]
JMap.Layer.getLayerIds

Returns an array with JMap layer ids.

The array order is the same as the one in the tree.

If no project is loaded, returns en empty array.

This function is equivalent to :
```
JMap.Layer.getLayers().map(layer => layer.id)
```
Returns JId[]
Example
```
// returns all JMap layer ids
JMap.Layer.getLayerIds()
```