Question

在我的Android项目中，我需要在车辆移动时，标记位置也应该平稳移动，但是当位置改变时，标记从一个位置跳到另一个位置，它不能平滑移动。

我搜索了很多，但没有得到结果我不知道最好的方法是什么。请给我完整的指导。

非常感谢

更新

@AnkitMehta谢谢你的回答

MapsActivity中的所有代码：

import android.Manifest;
import android.content.DialogInterface;
import android.content.pm.PackageManager;
import android.content.res.Resources;
import android.location.Location;
import android.os.Build;
import android.os.Handler;
import android.os.SystemClock;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v4.app.ActivityCompat;
import android.support.v4.app.FragmentActivity;
import android.os.Bundle;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AlertDialog;
import android.util.Log;
import android.view.animation.Interpolator;
import android.view.animation.LinearInterpolator;
import android.widget.Toast;

import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.location.LocationListener;
import com.google.android.gms.location.LocationRequest;
import com.google.android.gms.location.LocationServices;
import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.OnMapReadyCallback;
import com.google.android.gms.maps.SupportMapFragment;
import com.google.android.gms.maps.model.BitmapDescriptorFactory;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.MapStyleOptions;
import com.google.android.gms.maps.model.Marker;
import com.google.android.gms.maps.model.MarkerOptions;

public class MapsActivity extends FragmentActivity implements OnMapReadyCallback, GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener, LocationListener {

  private GoogleMap mMap;
  SupportMapFragment mapFragment;
  LocationRequest mLocationRequest;
  GoogleApiClient mGoogleApiClient;
  Location mLastLocation;
  Marker mCurrLocationMarker;

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_maps);
    // Obtain the SupportMapFragment and get notified when the map is ready to be used.
    mapFragment = (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map);
    mapFragment.getMapAsync(this);
  }

  @Override
  protected void onPause() {
    super.onPause();

    //stop Location updates when Activity is no longer active
    if (mGoogleApiClient != null) {
      LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this);
    }
  }


  @Override
  public void onMapReady(GoogleMap googleMap) {
    mMap = googleMap;

    try {
      // Customise the styling of the base map using a JSON object defined
      // in a raw resource file.
      boolean success = googleMap.setMapStyle(
        MapStyleOptions.loadRawResourceStyle(
          this, R.raw.style_json));

      if (!success) {
        Log.e("LOG" , "Style parsing failed.");
      }
    } catch (Resources.NotFoundException e) {
      Log.e("LOG", "Can't find style. Error: ", e);
    }

    //initialize Google play Services
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
      if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) {
        // Location Permission already granted
        buildGoogleApiClient();
        mMap.setMyLocationEnabled(true);

      } else {
        // Request Location Permission
        checkLocationPermission();
      }
    } else {
      buildGoogleApiClient();
      mMap.setMyLocationEnabled(true);
    }


  }

  protected synchronized void buildGoogleApiClient() {
    mGoogleApiClient = new GoogleApiClient.Builder(this)
      .addConnectionCallbacks(this)
      .addOnConnectionFailedListener(this)
      .addApi(LocationServices.API)
      .build();
    mGoogleApiClient.connect();
  }


  @Override
  public void onConnected(@Nullable Bundle bundle) {
    mLocationRequest = new LocationRequest();
    //mLocationRequest.setInterval(30000);
    //mLocationRequest.setFastestInterval(30000);
    mLocationRequest.setPriority(LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY);
    if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) {
      LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
    }
  }

  @Override
  public void onConnectionSuspended(int i) {

  }

  @Override
  public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {

  }

  @Override
  public void onLocationChanged(Location location) {
    mLastLocation = location;
    if (mCurrLocationMarker != null) {
      mCurrLocationMarker.remove();
    }

    //Place current location marker
    LatLng latLng = new LatLng(location.getLatitude(), location.getLongitude());
    animateMarker(latLng, latLng, true);


    //move map camera
    mMap.moveCamera(CameraUpdateFactory.newLatLngZoom(latLng,11));
    mMap.animateCamera(CameraUpdateFactory.newLatLngZoom(latLng, 11));
  }

  public static final int MY_PERMISSIONS_REQUEST_LOCATION = 99;
  private void checkLocationPermission() {
    if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION)
      != PackageManager.PERMISSION_GRANTED) {

      // Should we show an explanation?
      if (ActivityCompat.shouldShowRequestPermissionRationale(this,
        Manifest.permission.ACCESS_FINE_LOCATION)) {

        // Show an explanation to the user *asynchronously* -- don't block
        // this thread waiting for the user's response! After the user
        // sees the explanation, try again to request the permission.
        new AlertDialog.Builder(this)
          .setTitle("Location Permission Needed")
          .setMessage("This app needs the Location permission, please accept to use location functionality")
          .setPositiveButton("OK", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialogInterface, int i) {
              //Prompt the user once explanation has been shown
              ActivityCompat.requestPermissions(MapsActivity.this,
                new String[]{Manifest.permission.ACCESS_FINE_LOCATION},
                MY_PERMISSIONS_REQUEST_LOCATION );
            }
          })
          .create()
          .show();


      } else {
        // No explanation needed, we can request the permission.
        ActivityCompat.requestPermissions(this,
          new String[]{Manifest.permission.ACCESS_FINE_LOCATION},
          MY_PERMISSIONS_REQUEST_LOCATION );
      }
    }
  }

  @Override
  public void onRequestPermissionsResult(int requestCode,
                                         String permissions[], int[] grantResults) {
    switch (requestCode) {
      case MY_PERMISSIONS_REQUEST_LOCATION: {
        // If request is cancelled, the result arrays are empty.
        if (grantResults.length > 0
          && grantResults[0] == PackageManager.PERMISSION_GRANTED) {

          // permission was granted, yay! Do the
          // location-related task you need to do.
          if (ContextCompat.checkSelfPermission(this,
            Manifest.permission.ACCESS_FINE_LOCATION)
            == PackageManager.PERMISSION_GRANTED) {

            if (mGoogleApiClient == null) {
              buildGoogleApiClient();
            }
            mMap.setMyLocationEnabled(true);
          }

        } else {

          // permission denied, boo! Disable the
          // functionality that depends on this permission.
          Toast.makeText(this, "permission denied", Toast.LENGTH_LONG).show();
        }
        return;
      }

      // other 'case' lines to check for other
      // permissions this app might request
    }
  }


  //This methos is used to move the marker of each car smoothly when there are any updates of their position
  public void animateMarker(final LatLng startPosition, final LatLng toPosition,
                            final boolean hideMarker) {


    final Marker marker = mMap.addMarker(new MarkerOptions()
      .position(startPosition)
      .icon(BitmapDescriptorFactory.fromResource(R.drawable.car)));


    final Handler handler = new Handler();
    final long start = SystemClock.uptimeMillis();

    final long duration = 1000;
    final Interpolator interpolator = new LinearInterpolator();

    handler.post(new Runnable() {
      @Override
      public void run() {
        long elapsed = SystemClock.uptimeMillis() - start;
        float t = interpolator.getInterpolation((float) elapsed
          / duration);
        double lng = t * toPosition.longitude + (1 - t)
          * startPosition.longitude;
        double lat = t * toPosition.latitude + (1 - t)
          * startPosition.latitude;

        marker.setPosition(new LatLng(lat, lng));

        if (t < 1.0) {
          // Post again 16ms later.
          handler.postDelayed(this, 16);
        } else {
          if (hideMarker) {
            marker.setVisible(false);
          } else {
            marker.setVisible(true);
          }
        }
      }
    });
  }
}

Answer 1

CameraPosition cameraPosition = new CameraPosition.Builder()
                                .target(latLng)
                                .build();
CameraUpdate cu = CameraUpdateFactory.newCameraPosition(cameraPosition);
map.animateCamera(cu);

这将移动到通过动画选择的latlng（相机位置和相机更新使用）

Answer 2

覆盖此方法：

public function update(Request $request)
{
    $function=SystemFunction::where('id',$request->id)->first();
    $function->toggleIsActive()->save();
    return redirect('admin/system-functions')->with('status','successful');
}

此重写的方法正在GoogleMap类上实现，并且map变量是我们定义的用于加载google map实例的变量。

请参考：https://developers.google.com/maps/documentation/android-sdk/views

如何在Google地图中平滑移动当前位置？

2 个答案: