所以我写了一个类，它会找到用户的位置并找到它与另一个点之间的距离，但我有一个随机数生成器所以当我调用时我使用的方法我在我的活动中使用（重新启动活动）随机数我不想发生的变化。如果有人会告诉我如何在点击按钮时刷新用户位置而不重新启动整个活动，那将是一个很大的帮助
public class MapsActivity extends FragmentActivity implements
GoogleApiClient.ConnectionCallbacks,
GoogleApiClient.OnConnectionFailedListener,
LocationListener {
//These variable are initalized here as they need to be used in more than one methid
private double currentLatitude; //lat of user
private double currentLongitude; //long of user
Random rand = new Random();
int n = rand.nextInt(5) + 1;
int score = 0;
public static final String TAG = MapsActivity.class.getSimpleName();
private final static int CONNECTION_FAILURE_RESOLUTION_REQUEST = 9000;
private GoogleMap mMap; // Might be null if Google Play services APK is not available.
private GoogleApiClient mGoogleApiClient;
private LocationRequest mLocationRequest;
//contains lat and lon of another place
private void setUpMap() {
if (n == 1) {
MarkerOptions marker = new MarkerOptions().position(new LatLng(latitudeVillageApartmets, longitudeVillageApartments)).title("1"); //create marker
mMap.addMarker(marker); // adding marker
} else if (n == 2) {
MarkerOptions marker = new MarkerOptions().position(new LatLng(latitudeSU, longitudeSU)).title("2"); //create marker
mMap.addMarker(marker); // adding marker
} else if (n == 3) {
MarkerOptions marker = new MarkerOptions().position(new LatLng(latitudeArtsBuilding, longitudeArtsBuilding)).title("3"); //create marker
mMap.addMarker(marker); // adding marker
} else if (n == 4) {
MarkerOptions marker = new MarkerOptions().position(new LatLng(latitudeJH, longitudeJH)).title("4"); //create marker
mMap.addMarker(marker); // adding marker
} else if (n == 5) {
MarkerOptions marker = new MarkerOptions().position(new LatLng(latitudeForebell, longitudeForebell)).title("5"); //create marker
mMap.addMarker(marker); // adding marker
}
}
//contains your lat and lon
private void handleNewLocation(Location location) {
Log.d(TAG, location.toString());
currentLatitude = location.getLatitude();
currentLongitude = location.getLongitude();
LatLng latLng = new LatLng(currentLatitude, currentLongitude);
//mMap.addMarker(new MarkerOptions().position(new LatLng(currentLatitude, currentLongitude)).title("Current Location"));
MarkerOptions options = new MarkerOptions()
.position(latLng)
.title("You are here");
mMap.addMarker(options);
mMap.moveCamera(CameraUpdateFactory.newLatLngZoom((latLng), 11.0F));
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_maps);
setUpMapIfNeeded();
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
// Create the LocationRequest object
mLocationRequest = LocationRequest.create()
.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY)
.setInterval(10 * 1000) // 10 seconds, in milliseconds
.setFastestInterval(1 * 1000); // 1 second, in milliseconds
//Refresh button. Will reset the location of your flag
//If the user clicks the button, the activity is finished and restarted
Button button2=(Button) findViewById(R.id.button2);
button2.setOnClickListener(new View.OnClickListener() {
public void onClick (View w){
Intent intent = getIntent();
finish();
startActivity(intent);
}
@Override
protected void onResume() {
super.onResume();
setUpMapIfNeeded();
mGoogleApiClient.connect();
}
@Override
protected void onPause() {
super.onPause();
if (mGoogleApiClient.isConnected()) {
LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this);
mGoogleApiClient.disconnect();
}
}
private void setUpMapIfNeeded() {
// Do a null check to confirm that we have not already instantiated the map.
if (mMap == null) {
// Try to obtain the map from the SupportMapFragment.
mMap = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map))
.getMap();
// Check if we were successful in obtaining the map.
if (mMap != null) {
setUpMap();
}
}
}
@Override
public void onConnected(Bundle bundle) {
Location location = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);
if (location == null) {
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
}
else {
handleNewLocation(location);
}
}
@Override
public void onConnectionSuspended(int i) {
}
@Override
public void onConnectionFailed(ConnectionResult connectionResult) {
if (connectionResult.hasResolution()) {
try {
// Start an Activity that tries to resolve the error
connectionResult.startResolutionForResult(this, CONNECTION_FAILURE_RESOLUTION_REQUEST);
/*
* Thrown if Google Play services canceled the original
* PendingIntent
*/
} catch (IntentSender.SendIntentException e) {
// Log the error
e.printStackTrace();
}
} else {
/*
* If no resolution is available, display a dialog to the
* user with the error.
*/
Log.i(TAG, "Location services connection failed with code " + connectionResult.getErrorCode());
}
}
@Override
public void onLocationChanged(Location location) {
handleNewLocation(location);
}
}
请注意，如果代码存在问题，我会删除很多代码，因此它只是括号和内容。我刚发布了这一切，所以你知道发生了什么。我只想刷新你的位置，而不是整个活动
Intent intent = getIntent();
finish();
startActivity(intent);
答案 0 :(得分：0)
MarkerOptions markerOptions;
Marker marker;
private void setUpMap() {
if(marker!= null)
marker.remove();
markerOptions = null;
if (n == 1) {
markerOptions = new MarkerOptions().position(new LatLng(latitudeVillageApartmets, longitudeVillageApartments)).title("1"); //create marker
} else if (n == 2) {
markerOptions = new MarkerOptions().position(new LatLng(latitudeSU, longitudeSU)).title("2"); //create marker
} else if (n == 3) {
markerOptions = new MarkerOptions().position(new LatLng(latitudeArtsBuilding, longitudeArtsBuilding)).title("3"); //create marker
} else if (n == 4) {
markerOptions = new MarkerOptions().position(new LatLng(latitudeJH, longitudeJH)).title("4"); //create marker
} else if (n == 5) {
markerOptions = new MarkerOptions().position(new LatLng(latitudeForebell, longitudeForebell)).title("5"); //create marker
}
if(markerOptions!=null)
marker = mMap.addMarker(markerOptions); // adding marker
}
在你的onclicklistener上
button2.setOnClickListener(new View.OnClickListener() {
public void onClick (View w){
n = rand.nextInt(5) + 1;
setUpMap();
}
});
或者您可以使用marker.setPosition（LatLng）;如果您的标记不为空