I added polylines, but could not add an arrow with a direction on the google map, should be displayed below 
And as he approaches, more arrows appear, as shown below 
I tried to read different blogs and codes, but could not get the target
I used the following code snippet:
private void DrawArrowHead(MarkerOptions MO, GoogleMap mMap, LatLng from, LatLng to) { // obtain the bearing between the last two points double bearing = GetBearing(from, to); // round it to a multiple of 3 and cast out 120s double adjBearing = Math.round(bearing / 3) * 3; while (adjBearing >= 120) { adjBearing -= 120; } StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build(); StrictMode.setThreadPolicy(policy); // Get the corresponding triangle marker from Google URL url; Bitmap image = null; try { url = new URL("http://www.google.com/intl/en_ALL/mapfiles/dir_" + String.valueOf((int) adjBearing) + ".png"); try { // image = BitmapFactory.decodeStream(url.openConnection().getInputStream()); Log.d("HistoryDisplay", String.valueOf(adjBearing)); // image = BitmapFactory.decodeResource(getResources(), R.drawable.arrow); image = BitmapFactory.decodeResource(getResources(), allArrow.get((int) adjBearing)); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } } catch (MalformedURLException e) { // TODO Auto-generated catch block e.printStackTrace(); } if (image != null) { // Anchor is ratio in range [0..1] so value of 0.5 on x and y will center the marker image on the lat/long float anchorX = 0.5f; float anchorY = 0.5f; int offsetX = 0; int offsetY = 0; // images are 24px x 24px // so transformed image will be 48px x 48px //315 range -- 22.5 either side of 315 if (bearing >= 292.5 && bearing < 335.5) { offsetX = 24; offsetY = 24; } //270 range else if (bearing >= 247.5 && bearing < 292.5) { offsetX = 24; offsetY = 12; } //225 range else if (bearing >= 202.5 && bearing < 247.5) { offsetX = 24; offsetY = 0; } //180 range else if (bearing >= 157.5 && bearing < 202.5) { offsetX = 12; offsetY = 0; } //135 range else if (bearing >= 112.5 && bearing < 157.5) { offsetX = 0; offsetY = 0; } //90 range else if (bearing >= 67.5 && bearing < 112.5) { offsetX = 0; offsetY = 12; } //45 range else if (bearing >= 22.5 && bearing < 67.5) { offsetX = 0; offsetY = 24; } //0 range - 335.5 - 22.5 else { offsetX = 12; offsetY = 24; } Bitmap wideBmp; Canvas wideBmpCanvas; Rect src, dest; // Create larger bitmap 4 times the size of arrow head image wideBmp = Bitmap.createBitmap(image.getWidth() * 2, image.getHeight() * 2, image.getConfig()); wideBmpCanvas = new Canvas(wideBmp); src = new Rect(0, 0, image.getWidth(), image.getHeight()); dest = new Rect(src); dest.offset(offsetX, offsetY); wideBmpCanvas.drawBitmap(image, src, dest, null); // MO.position(to); MO.icon(BitmapDescriptorFactory.fromBitmap(wideBmp)); MO.anchor(anchorX, anchorY); mMap.addMarker(MO); // mMap.addMarker(new MarkerOptions() // .position(to) // .icon(BitmapDescriptorFactory.fromBitmap(wideBmp)) // .anchor(anchorX, anchorY)); } } private double GetBearing(LatLng from, LatLng to) { double lat1 = from.latitude * Math.PI / 180.0; double lon1 = from.longitude * Math.PI / 180.0; double lat2 = to.latitude * Math.PI / 180.0; double lon2 = to.longitude * Math.PI / 180.0; // Compute the angle. double angle = -Math.atan2(Math.sin(lon1 - lon2) * Math.cos(lat2), Math.cos(lat1) * Math.sin(lat2) - Math.sin(lat1) * Math.cos(lat2) * Math.cos(lon1 - lon2)); if (angle < 0.0) angle += Math.PI * 2.0; // And convert result to degrees. angle = angle * degreesPerRadian; return angle; }
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