Develop Reference

google maps android studio does not show my polyline

I don't know why this polyline won't show, I already put the google maps api and enabled the directions api as well
PolylineOptions rectOptions = new PolylineOptions();
rectOptions.add(new LatLng(24.009115, -104.699933));
rectOptions.add(new LatLng(24.009115, -104.699933));
rectOptions.width(5);
rectOptions.color(Color.RED);
Polyline polyline = mMap.addPolyline(rectOptions);

Add(), width() and color() all return a PolylineOptions with the new settings added.
PolylineOptions rectOptions = new PolylineOptions();
rectOptions =rectOptions.add(new LatLng(24.009115, -104.699933));
rectOptions =rectOptions.add(new LatLng(24.009115, -104.699933));
rectOptions =rectOptions.width(5);
rectOptions =rectOptions.color(Color.RED);
Polyline polyline = mMap.addPolyline(rectOptions);
or
PolylineOptions rectOptions = new PolylineOptions()
.add(new LatLng(24.009115,-104.699933),
new latlang(24.009115,-104.699933))
.width(5)
.color(Color.red);
Polyline polyline = mMap.addPolyline(rectOptions);
Source:https://developers.google.com/android/reference/com/google/android/gms/maps/model/PolylineOptions

Why is my Polygon on Google Maps Android API not Appearing?

I do this in my java class:
//this is in On Create
GameMapFragment map = new GameMapFragment();
onMapReady(map.googleMap);
...
public void onMapReady(GoogleMap map) {
map.moveCamera(CameraUpdateFactory.newLatLngZoom(
new LatLng(-18.142, 178.431), 2));
// Polylines are useful for marking paths and routes on the map.
map.addPolyline(new PolylineOptions().geodesic(true)
.add(new LatLng(-33.866, 151.195)) // Sydney
.add(new LatLng(-18.142, 178.431)) // Fiji
.add(new LatLng(21.291, -157.821)) // Hawaii
.add(new LatLng(37.423, -122.091)) // Mountain View
);
}
Yet all that shows up is my map without any points - not even a PolyLine. How do I make the polygon visible?

It looks like you should be calling map.getMapAsync(this); instead of onMapReady(map.googleMap); in onCreate (assuming your Activity implements OnMapReadyCallback).

Android google maps getting rid of polyline

I am building an android application that gets the users current position and find nearby attractions. When I select an attraction a route is drawn to it from the current position but when I do this a second time the first route stays there, I want it to disappear. Below is the code I use to draw the line. Each time a direction is drawn this is called. I have tried to use line.remove each time before method is called but this removes both lines then. Any suggestions?
for (int i = 0; i < pontos.size() - 1; i++) {
LatLng src = pontos.get(i);
LatLng dest = pontos.get(i + 1);
try{
//here is where it will draw the polyline in your map
line = mMap.addPolyline(new PolylineOptions()
.add(new LatLng(src.latitude, src.longitude),
new LatLng(dest.latitude, dest.longitude))
.width(2).color(Color.RED).geodesic(true));

Save your Polylines in an array so you can remove them before other ones are added:
List<Polyline> mPolylines = new ArrayList<>();
private void someMethod() {
// Remove polylines from map
for (Polyline polyline : mPolylines) {
polyline.remove();
}
// Clear polyline array
mPolylines.clear();
for (int i = 0; i < pontos.size() - 1; i++) {
LatLng src = pontos.get(i);
LatLng dest = pontos.get(i + 1);
mPolylines.add(mMap.addPolyline(new PolylineOptions()
.add(new LatLng(src.latitude, src.longitude),
new LatLng(dest.latitude, dest.longitude))
.width(2).color(Color.RED).geodesic(true)));
}
}

Remove a line from PolyLine map in Google Map android V2?

I have searched in google and find this answer where i can remove all polyLine of a Map.
But I want to remove only a particular line from the poly Line. For Example I want to remove the line from 2nd to 3rd LatLng in the given code. I want to change color of a particular line of a polyLine or make it transparent. And I also want to add a clickListener to PolyLine
PolylineOptions rectOptions = new PolylineOptions()
.add(new LatLng(37.35, -122.0))
.add(new LatLng(37.45, -122.0)) // North of the previous point, but at the same longitude
.add(new LatLng(37.45, -122.2)) // Same latitude, and 30km to the west
.add(new LatLng(37.35, -122.2)) // Same longitude, and 16km to the south
.add(new LatLng(37.35, -122.0)).width(5).color(Color.RED);; // Closes the polyline.
Polyline polyline = myMap.addPolyline(rectOptions);
Main goal is to remove/make it transparent a particular line of a PolyLine on click or tap.
PolylineOptions line= new PolylineOptions().add(HAMBURG,// these are latlong
KIEL,
KIEL2,
KIEL3
new LatLng(40.748963847316034,
-73.96807193756104)
)
.width(5).color(Color.RED);
Polyline polyline= googleMap.addPolyline(line);
And i want to remov line between KIEL1 and KIEL2

You'll have to manually remove points from the polyline.
EDIT:
Step by step:
Create a List of polylines:
List<Polyline> mPolylines = new ArrayList<Polyline>();
Add PolylineOptions to the map:
Polyline polyline1 = myMap.addPolyline(rectOptions1);
Polyline polyline2 = myMap.addPolyline(rectOptions2);
Polyline polyline3 = myMap.addPolyline(rectOptions3);
Then save the added polylines to your array
mPolylines.add(polyline1);
mPolylines.add(polyline2);
mPolylines.add(polyline3);
Now at any time you can trim the polyline like so:
// Get polyline1
List<LatLng> points = mPolylines.get(0).getPoints();
// Set the bounds of points to remove (inclusive)
int startPoint = 1, endPoint = 2; // will remove kiel1 and kiel2
// Remove the points
for (int i=startPoint; i<=endPoint; i++) {
points.remove(i);
}
// Added this line as getPoints returns a copy
mPolylines.get(0).setPoints(points);
Now in theory this should work fine. I found that the points don't actually change after setPoints.
I even tried:
Polyline polyline = mPolylines.get(0);
// Get copy of the points
List<LatLng> points = polyline.getPoints();
mPolylines.get(0).remove();
mPolylines.remove(0);
for (int i=3000; i<7000; i++) {
points.remove(i);
}
// Create a PolylineOptions object with the new points
PolylineOptions polylineOptions = new PolylineOptions().addAll(points);
mPolylines.add(0, mMap.addPolyline(polylineOptions));
And to my surprise a new Polyline was added (I can tell by the changed stroke width and color), but it still used the old points, even though points.size() returned the correct (trimmed) count.
I'm not sure why this is so, perhaps some error in my code. You can try these methods yourself and see if you are any luckier.

Android map v2 draw custom rectangle

I'm new to the google maps v2, I need to draw a rectangle from point1 to point2, with a custom color and width, I tried to use a Polyline, but all the labels (city name, country name ..) are still visible, so how can I do this ?
thank you
this is what I tried
mMapView.addPolyline(new PolylineOptions()
.add(new LatLng(xx,xx), new LatLng(xx,xx))
.width(50)
.color(Color.parseColor("#f4f3f0")));

Just read the Documentation
Example
GoogleMap map;
// ... get a map.
// Add a thin red line from London to New York.
Polyline line = map.addPolyline(new PolylineOptions()
.add(new LatLng(51.5, -0.1), new LatLng(40.7, -74.0))
.width(5)
.color(Color.RED));

Use
public class My_Map extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.map_activity);
GoogleMap map = ((MapFragment) getFragmentManager()
.findFragmentById(R.id.map)).getMap();
map.moveCamera(CameraUpdateFactory.newLatLngZoom(
new LatLng(-18.142, 178.431), 2));
// Polylines are useful for marking paths and routes on the map.
map.addPolyline(new PolylineOptions().geodesic(true)
.add(new LatLng(-33.866, 151.195))
.add(new LatLng(-18.142, 178.431))
.add(new LatLng(21.291, -157.821))
.add(new LatLng(37.423, -122.091))
);
}
}
For more details just check How to draw free hand polygon in Google map V2 in Android?