我是android编程的新手。我已经从数据库和当前位置检索了LatLng。问题是我不知道如何从两个标记画出路径。谢谢:)这是我的地图活动。
public class ModelMap extends AppCompatActivity implements OnMapReadyCallback, View.OnClickListener, GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener, LocationListener {
Button btnGo;
AutoCompleteTextView etSearch;
LatLng latLng;
GoogleMap mGoogleMap;
SupportMapFragment mFragment;
Marker currLocationMarker;
LocationRequest mLocationRequest;
GoogleApiClient mGoogleApiClient;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_model_map);
btnGo = (Button) findViewById(R.id.btnGo);
etSearch = (AutoCompleteTextView) findViewById(R.id.etSearch);
btnGo.setOnClickListener(this);
getMap();
}
@Override
public void onClick(View view) {
ArrayList<HashMap<String, String>> location = null;
String url = "http://enyatravel.com/maps/mapsdata/mapsModel.php";
try {
JSONArray data = new JSONArray(getHttpGet(url));
location = new ArrayList<HashMap<String, String>>();
HashMap<String, String> map;
for (int i = 0; i < data.length(); i++) {
JSONObject c = data.getJSONObject(i);
map = new HashMap<String, String>();
map.put("location_id", c.getString("location_id"));
map.put("latitude", c.getString("latitude"));
map.put("longitude", c.getString("longitude"));
map.put("name", c.getString("name"));
location.add(map);
}
} catch (JSONException e) {
e.printStackTrace();
}
mGoogleMap.getUiSettings().setMapToolbarEnabled(false);
mGoogleMap.getUiSettings().setCompassEnabled(false);
mGoogleMap.getUiSettings().setMyLocationButtonEnabled(false);
//zoom
Double latitude = Double.parseDouble(location.get(0).get("latitude").toString());
Double longitude = Double.parseDouble(location.get(0).get("longitude").toString());
LatLng coordinate = new LatLng(latitude, longitude);
mGoogleMap.setMapType(GoogleMap.MAP_TYPE_SATELLITE);
mGoogleMap.animateCamera(CameraUpdateFactory.newLatLngZoom(coordinate, 17));
//marker
for (int i = 0; i < location.size(); i++) {
latitude = Double.parseDouble(location.get(i).get("latitude").toString());
longitude = Double.parseDouble(location.get(i).get("longitude").toString());
String name = location.get(i).get("name").toString();
MarkerOptions marker = new MarkerOptions().position(new LatLng(latitude, longitude)).title(name);
mGoogleMap.addMarker(marker);
}
}
public void getMap() {
if (Build.VERSION.SDK_INT > 9) {
StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy);
}
mFragment = (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.googlemaps);
mFragment.getMapAsync(this);
}
public static String getHttpGet(String url) {
StringBuilder str = new StringBuilder();
HttpClient client = new DefaultHttpClient();
HttpGet httpget = new HttpGet(url);
try {
HttpResponse response = client.execute(httpget);
StatusLine statusLine = response.getStatusLine();
int statusCode = statusLine.getStatusCode();
if (statusCode == 200) { // Download OK
HttpEntity entity = response.getEntity();
InputStream content = entity.getContent();
BufferedReader reader = new BufferedReader(new InputStreamReader(content));
String line;
while ((line = reader.readLine()) != null) {
str.append(line);
}
} else {
Log.e("Log", "Failed to download result..");
}
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return str.toString();
}
@Override
public void onMapReady(GoogleMap googleMap) {
googleMap.setMapType(GoogleMap.MAP_TYPE_SATELLITE);
mGoogleMap = googleMap;
mGoogleMap.setMyLocationEnabled(true);
buildGoogleApiClient();
mGoogleApiClient.connect();
}
protected synchronized void buildGoogleApiClient() {
Toast.makeText(this, "buildGoogleApiClient", Toast.LENGTH_SHORT).show();
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
}
@Override
public void onConnected(Bundle bundle) {
Toast.makeText(this, "onConnected", Toast.LENGTH_SHORT).show();
Location mLastLocation = LocationServices.FusedLocationApi.getLastLocation(
mGoogleApiClient);
if (mLastLocation != null) {
//place marker at current position
//mGoogleMap.clear();
latLng = new LatLng(mLastLocation.getLatitude(), mLastLocation.getLongitude());
MarkerOptions markerOptions = new MarkerOptions();
markerOptions.position(latLng);
markerOptions.title("Current Position");
markerOptions.icon(BitmapDescriptorFactory.fromResource(R.drawable.icongps));
currLocationMarker = mGoogleMap.addMarker(markerOptions);
}
mLocationRequest = new LocationRequest();
// mLocationRequest.setInterval(5000); //5 seconds
// mLocationRequest.setFastestInterval(3000); //3 seconds
mLocationRequest.setPriority(LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY);
//mLocationRequest.setSmallestDisplacement(0.1F); //1/10 meter
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
}
@Override
public void onConnectionSuspended(int i) {
Toast.makeText(this, "onConnectionSuspended", Toast.LENGTH_SHORT).show();
}
@Override
public void onConnectionFailed(ConnectionResult connectionResult) {
Toast.makeText(this, "onConnectionFailed", Toast.LENGTH_SHORT).show();
}
@Override
public void onLocationChanged(Location location) {
//place marker at current position
//mGoogleMap.clear();
if (currLocationMarker != null) {
currLocationMarker.remove();
}
latLng = new LatLng(location.getLatitude(), location.getLongitude());
MarkerOptions markerOptions = new MarkerOptions();
markerOptions.position(latLng);
markerOptions.title("Current Position");
markerOptions.icon(BitmapDescriptorFactory.fromResource(R.drawable.icontao));
currLocationMarker = mGoogleMap.addMarker(markerOptions);
//Toast.makeText(this,"Location Changed",Toast.LENGTH_SHORT).show();
//zoom to current position:
mGoogleMap.moveCamera(CameraUpdateFactory.newLatLngZoom(latLng, 17));
//If you only need one location, unregister the listener
//LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this);
}
}
PHP：
$strSQL ="SELECT * FROM `loc_info` WHERE name= 'Saverde Coffee Shop'";
$objQuery = mysqli_query($objConnect, $strSQL);
// or die (mysqli_error());
$arrRows = array();
$arryItem = array();
while($arr = mysqli_fetch_array($objQuery)){
$arryItem["location_id"] = $arr["location_id"];
$arryItem["latitude"] = $arr["latitude"];
$arryItem["longitude"] = $arr["longitude"];
$arryItem["name"] = $arr["name"];
$arrRows[]= $arryItem;
}
echo json_encode($arrRows);
?>
答案 0 :(得分：1)
如果您想要绘制路径的两个点（标记），则必须使用latlong绘制PolliLines。下面的代码将在地图上绘制您的路径。
@IBOutlet weak var mapView: MKMapView!
//my location
let manager = CLLocationManager()
func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
let location = locations[0]
let span:MKCoordinateSpan = MKCoordinateSpanMake(0.01, 0.01)
let myLocation:CLLocationCoordinate2D = CLLocationCoordinate2DMake(location.coordinate.latitude, location.coordinate.longitude)
let region:MKCoordinateRegion = MKCoordinateRegionMake(myLocation, span)
mapView.setRegion(region, animated: true)
print(location.altitude)
print(location.speed)
self.mapView.showsUserLocation = true
}
override func viewDidLoad() {
super.viewDidLoad()
//my location
manager.delegate = self
manager.desiredAccuracy = kCLLocationAccuracyBest
manager.requestWhenInUseAuthorization()
manager.startUpdatingLocation()
let distanceSpan:CLLocationDegrees = 250
//KT1 Annotation
let KT1Location:CLLocationCoordinate2D = CLLocationCoordinate2DMake(22.310491, 114.227998)
mapView.setRegion(MKCoordinateRegionMakeWithDistance(KT1Location, distanceSpan, distanceSpan),animated: true)
let KT1CSClassPin = KT1Annotation(title: "觀塘工業中心第一期", subtitle: "觀塘道 472-484號", coordinate: KT1Location)
mapView.addAnnotation( KT1CSClassPin )
//KT2 Annotation
let KT2Location:CLLocationCoordinate2D = CLLocationCoordinate2DMake(22.310724, 114.227626)
mapView.setRegion(MKCoordinateRegionMakeWithDistance(KT2Location, distanceSpan, distanceSpan),animated: true)
let KT2CSClassPin = KT2Annotation(title: "觀塘工業中心第二期", subtitle: "觀塘道 460-470號", coordinate: KT2Location)
mapView.addAnnotation( KT2CSClassPin )
//KT3 Annotation
let KT3Location:CLLocationCoordinate2D = CLLocationCoordinate2DMake(22.310957, 114.227255)
mapView.setRegion(MKCoordinateRegionMakeWithDistance(KT3Location, distanceSpan, distanceSpan),animated: true)
let KT3CSClassPin = KT3Annotation(title: "觀塘工業中心第三期", subtitle: "觀塘道 448-458號", coordinate: KT3Location)
mapView.addAnnotation( KT3CSClassPin )
//KT4 Annotation
let KT4Location:CLLocationCoordinate2D = CLLocationCoordinate2DMake(22.311364, 114.226883)
mapView.setRegion(MKCoordinateRegionMakeWithDistance(KT4Location, distanceSpan, distanceSpan),animated: true)
let KT4CSClassPin = KT4Annotation(title: "觀塘工業中心第四期", subtitle: "觀塘道 436-446號", coordinate: KT4Location)
mapView.addAnnotation( KT4CSClassPin )
//CP1 Annotation
let CP1Location:CLLocationCoordinate2D = CLLocationCoordinate2DMake(22.310459, 114.22516470000005)
mapView.setRegion(MKCoordinateRegionMakeWithDistance(CP1Location, distanceSpan, distanceSpan),animated: true)
let CP1CSClassPin = CP1Annotation(title: "駱駝漆大廈第1座", subtitle: "開源道 62號", coordinate: CP1Location)
mapView.addAnnotation( CP1CSClassPin )
//CP3 Annotation
let CP3Location:CLLocationCoordinate2D = CLLocationCoordinate2DMake(22.310125, 114.225072)
mapView.setRegion(MKCoordinateRegionMakeWithDistance(CP3Location, distanceSpan, distanceSpan),animated: true)
let CP3CSClassPin = CP3Annotation(title: "駱駝漆大廈第3座", subtitle: "開源道 60號", coordinate: CP3Location)
mapView.addAnnotation( CP3CSClassPin )
}
只需点击链接即可。 Answer : Draw path between two points using Google Maps Android API v2
答案 1 :(得分：0)
您可以使用Polyline。我已经分享了链接，第一个将为您提供直接的简单实现。另一个是提高你的理解。