java - Google Location api 不显示坐标

Question

我正在使用 Google Play 服务来获取用户的当前位置并尝试将其显示在 TextView 中，但由于某种原因没有任何反应。没有日志打印出来， Activity 仍然显示“hello world”而不是坐标。该应用程序也符合要求并且可以正常运行。

编辑:如果有帮助，位置图标会在我的通知面板上显示几秒钟。

package com.trypickups.googlelocationservices;

import android.location.Location;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.TextView;

import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.location.LocationServices;


public class MainActivity extends ActionBarActivity implements
        GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener{
    private GoogleApiClient mGoogleApiClient;
    private Location mLastLocation;
    private TextView location;
    protected synchronized void buildGoogleApiClient() {
        mGoogleApiClient = new GoogleApiClient.Builder(this)
                .addConnectionCallbacks(this)
                .addOnConnectionFailedListener(this)
                .addApi(LocationServices.API)
                .build();
    }
    @Override

    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        buildGoogleApiClient();


    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }

    @Override
    public void onConnected(Bundle bundle) {
        final TextView mTextView = (TextView) findViewById(R.id.location);
        mTextView.setText("Latitude "+ String.valueOf(mLastLocation.getLatitude()) + " Longitude " + String.valueOf(mLastLocation.getLongitude()));
    }

    @Override
    public void onConnectionSuspended(int i) {

    }

    @Override
    public void onConnectionFailed(ConnectionResult connectionResult) {
        Log.e("Alesti", connectionResult.toString());

    }
}

Answer 1

您似乎忘记了调用 mGoogleApiClient.connect()，而且您也从未调用过 requestLocationUpdates()。

这是我测试过的有效代码:

public class MainActivity extends ActionBarActivity implements
        GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener, LocationListener {

    LocationRequest mLocationRequest;
    GoogleApiClient mGoogleApiClient;
    private Location mLastLocation;
    private TextView locationText;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        locationText = (TextView) findViewById(R.id.location);

        buildGoogleApiClient();
        mGoogleApiClient.connect();
    }

    @Override
    protected void onPause(){
        super.onPause();
        if (mGoogleApiClient != null) {
            LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this);
        }
    }

    protected synchronized void buildGoogleApiClient() {
        Toast.makeText(this,"buildGoogleApiClient",Toast.LENGTH_SHORT).show();
        mGoogleApiClient = new GoogleApiClient.Builder(this)
                .addConnectionCallbacks(this)
                .addOnConnectionFailedListener(this)
                .addApi(LocationServices.API)
                .build();
    }

    @Override
    public void onConnected(Bundle bundle) {
        Toast.makeText(this,"onConnected",Toast.LENGTH_SHORT).show();

        mLocationRequest = new LocationRequest();
        mLocationRequest.setInterval(5000);
        mLocationRequest.setFastestInterval(1000);
        mLocationRequest.setPriority(LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY);

        //mLocationRequest.setSmallestDisplacement(0.1F);

        LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
    }

    @Override
    public void onConnectionSuspended(int i) {
        Toast.makeText(this,"onConnectionSuspended",Toast.LENGTH_SHORT).show();
    }

    @Override
    public void onConnectionFailed(ConnectionResult connectionResult) {
        Toast.makeText(this,"onConnectionFailed",Toast.LENGTH_SHORT).show();
    }

    @Override
    public void onLocationChanged(Location location) {

        //Set contents of your TextView here
        locationText.setText("lat: " + location.getLatitude() + " lon: " + location.getLongitude());

        //set last location member variable
        mLastLocation = location;

        Log.d("locationtesting", "accuracy: " + location.getAccuracy() + " lat: " + location.getLatitude() + " lon: " + location.getLongitude());

        Toast.makeText(this,"Location Changed",Toast.LENGTH_SHORT).show();
    }
}