Assistance with <name> and <styleUrl> in .kml when using writeOGR() from rgdal - r

Question

I have a data frame containing coordinates to various locations that I'd like to use with Google Earth. Here's a simple example showing the structure:
data <- data.frame(country = "USA", city = "Saint Paul",
lat = 44.9629, lon = -93.00146)
I followed this SO post and this guide to create KML output successfully using the writeOGR() function from the rgdal package, however I'm having trouble tweaking the attributes. Here's the code:
# you may need to install gdal itself for the package to install successfully
# install.packages("rgdal")
library(rgdal)
data_sp <- data
coordinates(data_sp) <- c("lon", "lat")
proj4string(data_sp) <- CRS("+init=epsg:4238")
data_ll <- spTransform(data_sp, CRS("+proj=longlat +datum=WGS84"))
writeOGR(data_ll["city"], "/path/to/test.kml", driver = "KML", layer = "city")
The result works fine for just viewing locations, but I'd like to change the <styleUrl> attribute as well as have the <name> attribute populated. Without it, Google Earth shows locations with a [no name] attribute:
Here's the resultant .kml file:
<?xml version="1.0" encoding="utf-8" ?>
<kml xmlns="http://www.opengis.net/kml/2.2">
<Document><Folder><name>city</name>
<Placemark>
<ExtendedData><SchemaData schemaUrl="#city">
<SimpleData name="city">Saint Paul</SimpleData>
</SchemaData></ExtendedData>
<Point><coordinates>-93.001753817020003,44.96282130428127</coordinates></Point>
</Placemark>
</Folder>
<Schema name="city" id="city">
<SimpleField name="city" type="string"></SimpleField>
</Schema>
</Document></kml>
I need to either get a <name> element to populate with the SimpleField name="city" contents, or have <name>City</name> tags added to each <Placemark>. What I'd like is something like this as the final result (note added <Style> definition, <styleUrl> attribute for the <Placemark>, and <name> attribute added):
<?xml version="1.0" encoding="utf-8" ?>
<kml xmlns="http://www.opengis.net/kml/2.2">
<Document>
<Style id="custom">
<IconStyle>
<scale>1.5</scale>
<Icon>
<href>http://upload.wikimedia.org/wikipedia/commons/a/af/Tux.png</href>
</Icon>
</IconStyle>
</Style>
<Folder><name>city</name>
<Placemark>
<name>Saint Paul</name>
<styleUrl>#custom</styleUrl>
<ExtendedData><SchemaData schemaUrl="#city">
<SimpleData name="city">Saint Paul</SimpleData>
</SchemaData></ExtendedData>
<Point><coordinates>-93.001753817020003,44.96282130428127</coordinates></Point>
</Placemark>
</Folder>
<Schema name="city" id="city">
<SimpleField name="city" type="string"></SimpleField>
</Schema>
</Document></kml>
Here's what the result looks like (similar to what I'm aiming for):
The rgdal documentation mentions a layer_options attribute, but nothing intuitively stuck out to me...
layer_options = c("<name>????</name>")?
layer_options = c("<styleUrl>#custom</styleUrl")?
Something else?
The attempts above to pass a tag directly don't appear to affect the output.
There's not many examples I found in googling other than creating the default output from writeOGR(), as shown above. Thanks for any suggestions.

Answer 1

To expand on #jlhoward's answer above, I was able to use kmlPoints() to accomplish what I was looking for:
data <- data.frame(country = "USA", city = "Saint Paul",
lat = 44.9629, lon = -93.00146)
# you may need to install gdal itself for the package to install successfully
# install.packages("rgdal")
library(rgdal)
library(maptools)
data_sp <- data
coordinates(data_sp) <- c("lon", "lat")
proj4string(data_sp) <- CRS("+init=epsg:4238")
data_ll <- spTransform(data_sp, CRS("+proj=longlat +datum=WGS84"))
kmlPoints(data_ll["city"], kmlfile = "~/Desktop/test.kml",
name = data_ll$city,
icon = "http://upload.wikimedia.org/wikipedia/commons/a/af/Tux.png")
The output contains both the desired <name> attribute as well as a <Style> definition for the custom icon, which is applied successfully to the <Placemark> entries:
readLines("test.kml")
readLines("test.kml")
[1] "<?xml version=\"1.0\" encoding=\"UTF-8\"?>"
[2] "<kml xmlns=\"http://earth.google.com/kml/2.2\">"
[3] "<Document>"
[4] "<name></name>"
[5] "<description><![CDATA[]]></description>"
[6] ""
[7] "<Style id=\"style1\">"
[8] " <IconStyle>"
[9] " <Icon>"
[10] " <href>http://upload.wikimedia.org/wikipedia/commons/a/af/Tux.png</href>"
[11] " </Icon>"
[12] " </IconStyle>"
[13] "</Style>"
[14] ""
[15] "<Placemark>"
[16] " <name>Saint Paul</name>"
[17] " <description><![CDATA[]]></description>"
[18] " <styleUrl>#style1</styleUrl>"
[19] " <Point>"
[20] " <coordinates>"
[21] "-93.00175381702,44.9628213042813"
[22] " </coordinates>"
[23] " </Point>"
[24] "</Placemark>"
[25] "</Document>"
[26] "</kml>"
The result:

Answer 2

Well, if all you want to do is populate the <name> element in each <Placemark>, this will do it:
library(maptools)
kmlPoints(data_ll,"test.kml",name=data$city)
readLines("test.kml")
# [1] "<?xml version=\"1.0\" encoding=\"UTF-8\"?>"
# [2] "<kml xmlns=\"http://earth.google.com/kml/2.2\">"
# [3] "<Document>"
# [4] "<name></name>"
# ...
# [15] "<Placemark>"
# [16] " <name>Saint Paul</name>"
# [17] " <description><![CDATA[]]></description>"
# [18] " <styleUrl>#style1</styleUrl>"
# [19] " <Point>"
# [20] " <coordinates>"
# [21] "-93.00175381702,44.9628213042813"
# [22] " </coordinates>"
# [23] " </Point>"
# [24] "</Placemark>"
# [25] "</Document>"
# [26] "</kml>"
If you need to change the <Style> as well, then I'm afraid you may have to hack the kml file using the XML package.