Xamarin.Android Couchbase.Lite Map Reduce - couchbase-lite

Question

I simply want to create a View that uses Map-Reduce to do this: Say I have Documents for the Automobile Industry. I would like the user to query for a particular Make - say Ford for example. I would like the user to provide the Ford value via an EditText, Tap a Button, and the "Count" be shown in a TextView. So, to clarify, I want to do a count of a certain type of Document using Map-Reduce. I have searched for over 100 hundred hours on this and have not found not one single example - REAL example I mean. (I have read all the docs, only generic examples - no actual examples)
I am an experienced programmer 15+ yrs exp - all I need is one example, and I am good to go.
Can someone please assist me with this?
Thanks,
Don

Answer 1

Here is my Actual Code:
string lMS = "MS:5"; // just to show what type of value I am using
var msCount = dbase.GetView ("count_ms");
msCount.SetMapReduce ((doc, emit) => {
if (doc.ContainsKey ("DT") && doc["DT"].Equals ("P")) {
if (doc.ContainsKey ("MS") && doc["MS"].Equals (_ms))
{
emit (doc ["id"], 1);
}
}
},
(keys, values, rereduce) => values.ToList().Count, "1");
var mscView = dbase.GetView ("count_ms");
var query = mscView.CreateQuery ();
query.StartKey = "MS:1";
query.EndKey = "MS:9999";
var queryResults = query.Run ();
var nr = queryResults.Count; // shows a value of 1 - wrong - should be 40
// the line below is to allow me to put a stop statement to read line above
var dummyForStop = nr;

Answer 2

Try setting something like
var docsByMakeCount = _database.GetView("docs_by_make_count");
docsByMakeCount.SetMapReduce((doc, emit) =>
{
if (doc.ContainsKey("Make"))
{
emit(doc["Make"], doc);
}
},
(keys, values, rereduce) => values.ToList().Count
, "1");
when you create your view.
and when you use it:
var docsByMake = _database.GetView("docs_by_make_count");
var query = docsByCity.CreateQuery();
query.StartKey = Make;
query.EndKey = Make;
var queryResults = query.Run();
MessageBox.Show(string.Format("{0} documents has been retrieved for that query", queryResults.Count));
if (queryResults.Count == 0) return;
var documents = queryResults.Select(result => JsonConvert.SerializeObject(result.Value, Formatting.Indented)).ToArray();
var commaSeperaterdDocs = "[" + string.Join(",", documents) + "]";
DocumentText = commaSeperaterdDocs;
In my case Make and DocumentText are properties.
There are some optimizations to be made here, like rereducing, but it's the straight forward way.