我正在创建一个应用程序,它将从中获取用户名DB
并打印ID
,然后单击按钮将显示当前的GPS coordinates
. 我已经实现了它,但不知道为什么它不起作用。
这是我的Manifest
文件
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
下面是我的MainActivity.java
public class MainActivity extends AppCompatActivity implements GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener, LocationListener {
private static final String TAG = "MainActivity";
private TextView tv_lat;
private TextView tv_long;
private Button btn_loc;
private GoogleApiClient googleApiClient;
private Location location;
private LocationManager mLocationManager;
private LocationManager locationManager;
private LocationRequest locationRequest;
private LocationListener locationListener;
private long UPDATE_INTERVAL = 2 * 1000; /* 10 secs */
private long FASTEST_INTERVAL = 2000; /* 2 sec */
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
tv_lat = (TextView)findViewById(R.id.tv_lat);
tv_long = (TextView)findViewById(R.id.tv_long);
btn_loc = (Button)findViewById(R.id.btn_loc);
// show location button click event
btn_loc.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
googleApiClient = new GoogleApiClient.Builder(MainActivity.this)
.addConnectionCallbacks(MainActivity.this)
.addOnConnectionFailedListener(MainActivity.this)
.addApi(LocationServices.API)
.build();
}
});
mLocationManager = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
checkLocation(); //check whether location service is enable or not in your phone
}
@Override
public void onConnected(Bundle bundle) {
if(ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED &&
ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED )
{
// TODO: Consider calling
// ActivityCompat#requestPermissions
// here to request the missing permissions, and then overriding
// public void onRequestPermissionsResult(int requestCode, String[] permissions,
// int[] grantResults)
// to handle the case where the user grants the permission. See the documentation
// for ActivityCompat#requestPermissions for more details.
return;
}
startLocationUpdates();
location = LocationServices.FusedLocationApi.getLastLocation(googleApiClient);
if(location == null)
{
startLocationUpdates();
}
if (location != null)
{
}
else {
Toast.makeText(this, "Location not Detected", Toast.LENGTH_SHORT).show();
}
}
@Override
public void onConnectionSuspended(int i) {
Log.i(TAG, "Connection Suspended");
googleApiClient.connect();
}
@Override
public void onConnectionFailed(ConnectionResult connectionResult) {
Log.i(TAG, "Connection failed. Error: " + connectionResult.getErrorCode());
}
@Override
protected void onStart() {
super.onStart();
if (googleApiClient != null) {
googleApiClient.connect();
}
}
@Override
protected void onStop() {
super.onStop();
if (googleApiClient.isConnected()) {
googleApiClient.disconnect();
}
}
private void startLocationUpdates() {
// Create the location request
locationRequest = LocationRequest.create()
.setPriority(LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY)
.setInterval(UPDATE_INTERVAL)
.setFastestInterval(FASTEST_INTERVAL);
// Request location updates
if(ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED &&
ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED )
{
// TODO: Consider calling
// ActivityCompat#requestPermissions
// here to request the missing permissions, and then overriding
// public void onRequestPermissionsResult(int requestCode, String[] permissions,
// int[] grantResults)
// to handle the case where the user grants the permission. See the documentation
// for ActivityCompat#requestPermissions for more details.
return;
}
LocationServices.FusedLocationApi.requestLocationUpdates(googleApiClient,
locationRequest, this);
Log.d("reque", "--->>>>");
}
@Override
public void onLocationChanged(Location location) {
double lattitude = location.getLatitude();
double longitude = location.getLongitude();
String msg = "Updated Location: " +
Double.toString(lattitude) + " , " +
Double.toString(longitude);
tv_lat.setText("Latitude is " + lattitude );
tv_long.setText("Longitude is " + longitude);
Toast.makeText(this, msg, Toast.LENGTH_SHORT).show();
// You can now create a LatLng Object for use with maps
LatLng latLng = new LatLng(location.getLatitude(), location.getLongitude());
}
private boolean checkLocation() {
if(!isLocationEnabled())
showAlert();
return isLocationEnabled();
}
private boolean isLocationEnabled() {
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
return locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER) ||
locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
}
public static final int MY_PERMISSIONS_REQUEST_LOCATION = 99;
private void showAlert() {
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)) {
final AlertDialog.Builder dialog = new AlertDialog.Builder(this);
dialog.setTitle("Enable Location")
.setMessage("Your Locations Settings is set to 'Off'.\nPlease Enable Location to " +
"use this app")
.setPositiveButton("Location Settings", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface paramDialogInterface, int paramInt) {
Intent myIntent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
startActivity(myIntent);
}
})
.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface paramDialogInterface, int paramInt) {
}
});
dialog.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 );
}
}
}
当我在我的设备上运行我的应用程序时,会显示以下结果
当我点击get location coordinates
什么都没有发生。中也没有显示错误或警告logcat
。
更新 1
我已将所有代码从button click
事件中移出
googleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
googleApiClient.connect();
mLocationManager = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
然后调试它,我得到了以下结果。
我不知道为什么没有显示坐标:(
任何帮助将不胜感激。