我的应用不需要动态位置更新。只有在(1)应用程序启动时才需要该位置; (2)打开特定活动/片段; (3)用户点击“获取我的位置”按钮。
标准是:当要求时,即使粗略地(如果可能的话)最小电池消耗,该位置也必须快速。我计划使用以下方法:
public void getLocation() {
LocationManager locationManager = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
Location location = locationManager.getLastKnownLocation(LocationManager.PASSIVE_PROVIDER);
if(location != null) {
//save the location to shared prefs to use when needed
return;
}
location = locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
if(location != null) {
//save the location to shared prefs to use when needed
return;
}
location = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if(location != null) {
//save the location to shared prefs to use when needed
return;
}
// if reached that point the location cannot be got!!
}
计划是每次应用程序启动时调用该方法,或者激活特定页面,或者用户想要获取当前位置。除非这些操作触发位置更新,否则旧位置或没有位置就足够了。这种方法有意义吗?如果不实现Location Listener和/或调用方法“requestLocationUpdates()”,我可以这样做吗?我担心的是“getLastKnownLocation()”在调用时可能不会给出当前位置,因为我不确定提供者的“最后知道位置”的更新频率或条件是多少。
非常感谢任何建议和意见。
答案 0 :(得分:1)
使用以下代码使用Google位置服务API获取当前和最后一个已知位置
//Global Variable
Location location;
public class MainActivity extends ActionBarActivity implements
GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener,
LocationListener {
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
mLocationRequest = LocationRequest.create()
.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY)
.setInterval(10 * 1000) // 10 seconds, in milliseconds
.setFastestInterval(1 * 1000); // 1 second, in milliseconds
@Override
protected void onResume() {
super.onResume();
mGoogleApiClient.connect();
}
@Override
protected void onPause() {
super.onPause();
if (mGoogleApiClient.isConnected()) {
LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this);
mGoogleApiClient.disconnect();
}
}
@Override
public void onConnected(Bundle bundle) {
location = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);
if (location == null) {
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
} else {
handleNewLocation(location);
}
}
@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);
} catch (IntentSender.SendIntentException e) {
e.printStackTrace();
}
} else {
Log.i(TAG, "Location services connection failed with code " + connectionResult.getErrorCode());
}
}
AnyActivity.class
MainActivity main = new MainActivity();
Location location = main.location;