(Android) Google Map 이동한 거리 선(polyline) 으로 그리기

Android Google Map Polyline

• Google Map 라이브러리를 사용하여 지도 관련 프로젝트를 진행하고 있습니다.
  • GPS를 통해 걸음을 체크하는 서비스  
• 걸음 시작 버튼을 누른 후부터 특정 주기로 GPS를 기록하여 이동한 거리를 선으로 그려주는 기능을 구현하고 싶었다. 

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구현방법

• Google Map 라이브러리에서 제공하는 Polyline이라는 기능을 통해서 지도 상에 line을 그릴수 있습니다.
• 걸음시작 버튼을 누른 순간부터 GPS 정보가 업데이트 됨에 따라서 선을 그려주는 방식입니다.
• GPS 정보는 onLocationChanged 라는 메소드가 호출될 때마다 업데이트가 되며 이때 이전 위치, 현재 위치를 선으로 그러줍니다.

public class MainActivity extends AppCompatActivity
        implements
        NavigationView.OnNavigationItemSelectedListener,
        OnMapReadyCallback,
        GoogleApiClient.ConnectionCallbacks,
        GoogleApiClient.OnConnectionFailedListener,
        ActivityCompat.OnRequestPermissionsResultCallback,
        LocationListener {
 
    private static final int LOCATION_PERMISSION_REQUEST_CODE = 1;
 
    private GoogleMap mMap;
    private GoogleApiClient mGoogleApiClient;
    private LocationRequest mLocationRequest;
    private Location mCurrentLocation;
    private FusedLocationProviderApi mFusedLocationProviderApi;
    private boolean mPermissionDenied;
    private LocationManager locationManager;
    private Marker mCurrentMarker;
    private LatLng startLatLng = new LatLng(0, 0);        //polyline 시작점 
    private LatLng endLatLng = new LatLng(0, 0);        //polyline 끝점
    private boolean walkState = false;                    //걸음 상태
 
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
 
        FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {               
                changeWalkState();        //걸음 상태 변경
            }
        });
 
        SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
                .findFragmentById(R.id.map);
        mapFragment.getMapAsync(this);
 
        if (mGoogleApiClient == null) {
            mGoogleApiClient = new GoogleApiClient.Builder(this)
                    .addApi(LocationServices.API)
                    .addConnectionCallbacks(this)
                    .addOnConnectionFailedListener(this)
                    .build();
        }
        createLocationRequest();
    }
 
    private void changeWalkState(){
        if(!walkState) {
            Toast.makeText(getApplicationContext(), "걸음 시작", Toast.LENGTH_SHORT).show();
            walkState = true;
            startLatLng = new LatLng(mCurrentLocation.getLatitude(), mCurrentLocation.getLongitude());        //현재 위치를 시작점으로 설정
        }else{
            Toast.makeText(getApplicationContext(), "걸음 종료", Toast.LENGTH_SHORT).show();
            walkState = false;
        }
    }
 
    private void drawPath(){        //polyline을 그려주는 메소드
        PolylineOptions options = new PolylineOptions().add(startLatLng).add(endLatLng).width(15).color(Color.BLACK).geodesic(true);
        polylines.add(mMap.addPolyline(options));
        mMap.moveCamera(CameraUpdateFactory.newLatLngZoom(startLatLng, 18));
    }
    @Override
    protected void onStart() {
        super.onStart();
        mGoogleApiClient.connect();
    }
 
    @Override
    protected void onStop() {
        super.onStop();
        mGoogleApiClient.disconnect();
    }
 
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }
 
    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        int id = item.getItemId();
        return super.onOptionsItemSelected(item);
    }
 
    @Override
    public void onMapReady(GoogleMap googleMap) {
        mMap = googleMap;
    }
 
    @Override
    public void onConnected(@Nullable Bundle bundle) {
        enableMyLocation();
    }
 
    @Override
    public void onConnectionSuspended(int i) {
 
    }
 
    @Override
    public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {
 
    }
 
    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions,
                                           @NonNull int[] grantResults) {
        if (requestCode != LOCATION_PERMISSION_REQUEST_CODE) {
            return;
        }
 
        if (PermissionUtils.isPermissionGranted(permissions, grantResults,
                Manifest.permission.ACCESS_FINE_LOCATION)) {
            // Enable the my location layer if the permission has been granted.
            enableMyLocation();
        } else {
            // Display the missing permission error dialog when the fragments resume.
            mPermissionDenied = true;
        }
    }
    @Override
    public void onLocationChanged(Location location) {
        double latitude = location.getLatitude(), longtitude = location.getLongitude();
 
        if (mCurrentMarker != null) mCurrentMarker.remove();
        mCurrentLocation = location;
        MarkerOptions markerOptions = new MarkerOptions();
        markerOptions.position(new LatLng(latitude, longtitude));
        mCurrentMarker =  mMap.addMarker(markerOptions);
 
 
        mMap.animateCamera(CameraUpdateFactory.newLatLngZoom(
                new LatLng(mCurrentLocation.getLatitude(), mCurrentLocation.getLongitude()), 18));
        if(walkState){                        //걸음 시작 버튼이 눌렸을 때
                endLatLng = new LatLng(latitude, longtitude);        //현재 위치를 끝점으로 설정
                drawPath();                                            //polyline 그리기
                startLatLng = new LatLng(latitude, longtitude);        //시작점을 끝점으로 다시 설정
        }
    }
 
    private void enableMyLocation() {
        if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION)
                != PackageManager.PERMISSION_GRANTED) {
            // Permission to access the location is missing.
            PermissionUtils.requestPermission(this, LOCATION_PERMISSION_REQUEST_CODE,
                    Manifest.permission.ACCESS_FINE_LOCATION, true);
        } else if (mMap != null) {
            mCurrentLocation = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);
            // Start location updates.
            LocationServices.FusedLocationApi.requestLocationUpdates(
                    mGoogleApiClient, mLocationRequest, this);
 
            if (mCurrentLocation != null) {
                Log.i("Location", "Latitude: " + mCurrentLocation.getLatitude()
                        + ", Longitude: " + mCurrentLocation.getLongitude());
            }
        }
    }
    protected void createLocationRequest() {
        mLocationRequest = new LocationRequest();
        mLocationRequest.setInterval(10000);
        mLocationRequest.setFastestInterval(5000);
        mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
    }
}