我只需要我的程序的纬度,经度和海拔高度,这是我的代码,但似乎onLocationChanged永远不会被调用。
MainActivity.Java
public class MainActivity extends AppCompatActivity implements LocationListener {
protected LocationManager locationManager;
protected LocationListener locationListener;
protected Context context;
double MyLong=0;
double MyLati=0;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
txtLat = (TextView) findViewById(R.id.textview1);
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) == PackageManager.PERMISSION_GRANTED) { // coarse permission is granted
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER,
0, 0, this);
}
else { // permission is not granted, request for permission
if (ActivityCompat.shouldShowRequestPermissionRationale(this, Manifest.permission.ACCESS_COARSE_LOCATION)) { // show some info to user why you want this permission
Toast.makeText(this, "Allow Location Permission to use this functionality.", Toast.LENGTH_SHORT).show();
ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.ACCESS_FINE_LOCATION, Manifest.permission.ACCESS_COARSE_LOCATION}, 123 /*LOCATION_PERMISSION_REQUEST_CODE*/);
} else {
ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.ACCESS_FINE_LOCATION, Manifest.permission.ACCESS_COARSE_LOCATION}, 123 /*LOCATION_PERMISSION_REQUEST_CODE*/);
}
}
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER,
0, 0, this);
}
@Override
onLocationChanged(Location location){
MyLong = location.getLongitude(); // this is Y in my map
MyLati = location.getLatitude(); // this is X in my map
txtLat = (TextView) findViewById(R.id.textview1);
String msg = "Coordinates are: long:" + MyLong + " lati: "+MyLati;
txtLat.setText(" "+msg+" ");
AndroidManifest
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.staykov.sunlight">
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.CHANGE_NETWORK_STATE" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
如何让onChangeLocation工作?这段代码有什么问题?我确实获得了我的初始字符串“Hello world”,但它没有更改为包含经度和纬度的字符串。如果我不得不猜测我在onCreate上做错了什么,但我不知道是什么。
另一件事是“受保护的LocationListener locationListener;”从未使用过。