Mapview draw route path

Question

My Problem is I have 4 Location's Latitude and Longitude into my local database, I am fetching those data and use for draw route path in android but problem is first to second location route is not display on mapview other second to third and third to fourth route path is display on mapview. Sorry for bad English communication.

i am getting code from following link for draw route path.

MapRoute Example

and call drawing class using following function:-

public void drawpath(){
        mDb.open();
        Cursor cr = mDb.getAllTitles();
        cr.moveToFirst();

        if (cr.getCount() > 0) {
            for (int i = 0; i <= cr.getCount()/2; i++) {
                fromlat = Double.parseDouble(cr.getString(1));
                fromlng = Double.parseDouble(cr.getString(2));
                cr.moveToNext();
                tolat = Double.parseDouble(cr.getString(1));
                tolng = Double.parseDouble(cr.getString(2));

                String url = RoadProvider
                        .getUrl(fromlat, fromlng, tolat, tolng);
                InputStream is = getConnection(url);
                mRoad = RoadProvider.getRoute(is);
                MapOverlay mapOverlay = new MapOverlay(mRoad, mapView);
                List<Overlay> listOfOverlays = mapView.getOverlays();
                listOfOverlays.add(mapOverlay);
                mapView.invalidate();
            }
        }

        cr.close();
        mDb.close();
    }

see this http://stackoverflow.com/questions/8612524/android-url-to-access-kml-route — NagarjunaReddy, Feb 06 '12 at 07:24
I am using that code but the Problem is same, the only first to second location path is not displaying the others are displaying... — Dipak Keshariya, Feb 06 '12 at 07:29
It's because you are only looping for half of the coordinates : `cr.getCount()/2` — Reno, Feb 06 '12 at 08:31

score 0 · Answer 1 · answered Feb 06 '12 at 07:52

0

Intent intent = new Intent(android.content.Intent.ACTION_VIEW, 
Uri.parse("http://maps.google.com/maps?saddr=20.344,34.34&daddr=20.5666,45.345"));
startActivity(intent);

answered Feb 06 '12 at 07:52

Ramesh Solanki

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score 0 · Answer 2 · answered Feb 06 '12 at 08:44

It is happening because you are using cr.getCount()/2.

When you will have even number of count then it will work not work fine

For example if you have 4 number of rows then you cr.getCount()/2 = 2 so your loop will continue from 0 to 2 means 3 times. Actually it should be continue 2 times as your coding.

Now lat take a odd numbers say 5 so cr.getCount()/2 = 2 because i is the integer value so your loop will work total 3 times.

So you have different mechanism.

Like try to add all the lat and long in the arraylist and then after loop complete.

Make a loop of the size of that arrayList and create a path.May be for that you required two additional variable to store the previous lat and long.

Mapview draw route path

2 Answers2