4

我的应用程序不想使用 GPS 并使用网络来获取位置。我通过分析纬度和经度检查了一下,它们有点随机(如网络位置)。

如果我使用另一个使用 GPS 的应用程序(例如 Endomondo 运动追踪器),我会看到特征标记,这意味着 GPS 当前正在工作:

在此处输入图像描述

当我启动我的应用程序时,根本没有任何标记。

我正在使用以下代码(Lars Vogella 的代码,来源:http ://www.vogella.com/articles/AndroidLocationAPI/article.html ):

import android.app.Activity;
import android.content.Context;
import android.location.Criteria;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.widget.TextView;
import android.widget.Toast;

public class ShowLocationActivity extends Activity implements LocationListener {
  private TextView latituteField;
  private TextView longitudeField;
  private LocationManager locationManager;
  private String provider;


/** Called when the activity is first created. */

  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    latituteField = (TextView) findViewById(R.id.TextView02);
    longitudeField = (TextView) findViewById(R.id.TextView04);

    // Get the location manager
    locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
    // Define the criteria how to select the locatioin provider -> use
    // default
    Criteria criteria = new Criteria();
    provider = locationManager.getBestProvider(criteria, false);
    Location location = locationManager.getLastKnownLocation(provider);

    // Initialize the location fields
    if (location != null) {
      System.out.println("Provider " + provider + " has been selected.");
      onLocationChanged(location);
    } else {
      latituteField.setText("Location not available");
      longitudeField.setText("Location not available");
    }
  }

  /* Request updates at startup */
  @Override
  protected void onResume() {
    super.onResume();
    locationManager.requestLocationUpdates(provider, 400, 1, this);
  }

  /* Remove the locationlistener updates when Activity is paused */
  @Override
  protected void onPause() {
    super.onPause();
    locationManager.removeUpdates(this);
  }

  @Override
  public void onLocationChanged(Location location) {
    int lat = (int) (location.getLatitude());
    int lng = (int) (location.getLongitude());
    latituteField.setText(String.valueOf(lat));
    longitudeField.setText(String.valueOf(lng));
  }

  @Override
  public void onStatusChanged(String provider, int status, Bundle extras) {
    // TODO Auto-generated method stub

  }

  @Override
  public void onProviderEnabled(String provider) {
    Toast.makeText(this, "Enabled new provider " + provider,
        Toast.LENGTH_SHORT).show();

  }

  @Override
  public void onProviderDisabled(String provider) {
    Toast.makeText(this, "Disabled provider " + provider,
        Toast.LENGTH_SHORT).show();
  }
} 

当然我在AndroidManifest.xml文件中添加了权限:

<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.INTERNET" />

有任何想法吗?

4

1 回答 1

5

解决方案: 您可以使用GPS而不是通过确定标准来选择最佳提供商。

示例,替换:

locationManager.requestLocationUpdates(provider, 400, 1, this);

和:

locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 400, 1, this);

解释:

根据您的应用程序的用例,您必须选择特定的位置提供程序,即LocationManager.GPS_PROVIDERLocationManager.NETWORK_PROVIDER

或者,您可以提供一些输入标准,例如准确性、功率要求、货币成本等,并让 Android 决定最接近的匹配位置提供程序

    // Retrieve a list of location providers that have fine accuracy, no monetary cost, etc
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
criteria.setCostAllowed(false);
String providerName = locManager.getBestProvider(criteria, true);
//and then you can make location update request with selected best provider
locationManager.requestLocationUpdates(provider, 400, 1, this); 

查看如何使用 locationmanager如何指定 Criteria以及getBestProvider 方法如何工作以供参考

于 2013-05-14T16:33:01.513 回答