public boolean isNetKeyAdded(final int keyIndex) {
        final ProvisionedMeshNode node = getSelectedMeshNode().getValue();
        if (node != null) {
            return MeshParserUtils.isNodeKeyExists(node.getAddedNetKeys(), keyIndex);
        }
        return false;
    }
Checks if the key has been added to the node

@param keyIndex index of the key
@return true if added or false otherwise
app/src/main/java/no/nordicsemi/android/nrfmesh/viewmodels/AddKeysViewModel.java