1.How to registry event or listener add feature Layer to map complete
2. How to listener Basemap change
1. I'm not sure I understand your question. Do you want to be notified when a FeatureLayer that has been added to the map has been loaded? If so, you can call FeatureLayer.addDoneLoadingListener to add a listener that gets invoked when loading of that layer has completed. More info about that here: https://developers.arcgis.com/android/latest/guide/loadable-pattern.htm2. You can listen to the BasemapChanged event via the BasemapChangedListener.
thank you very much
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