Question

我正在尝试使用Google Play服务创建Android位置API。但我继续得到＆＃34; java.lang.IllegalStateException：需要GoogleApiClient＆＃34;。谁能告诉我我做错了什么？这是我一直在尝试的代码。

CODE：

package com.example.jamshi.locationapi;

import android.app.Activity;
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.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;

import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.GooglePlayServicesUtil;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.common.api.GoogleApiClient.ConnectionCallbacks;
import com.google.android.gms.common.api.GoogleApiClient.OnConnectionFailedListener;
import com.google.android.gms.location.LocationListener;
import com.google.android.gms.location.LocationRequest;
import com.google.android.gms.location.LocationServices;

 public class MainActivity extends Activity implements ConnectionCallbacks,OnConnectionFailedListener {

    private static final String TAG = MainActivity.class.getSimpleName();
    private static final int PLAY_SERVICES_RESOLUTION_REQUEST = 1000;
    private Location mLastLocation;
    private GoogleApiClient mGoogleApiClient;


    private TextView tvLocation;
    private Button btnShowLocation,btnLocationUpdates;


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

        tvLocation = (TextView) findViewById(R.id.tvLocation);
        btnShowLocation = (Button) findViewById(R.id.btnShowLocation);
        btnLocationUpdates = (Button) findViewById(R.id.btnLocationUpdates);

        boolean checkPlayServices = false;
        if(checkPlayServices){
            buildApiClient();
        }

        btnShowLocation.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                displayLocation();
            }
        });



    }

    private void displayLocation() {
         //buildApiClient();
        mLastLocation = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);

        if (mLastLocation != null) {
            double latitude = mLastLocation.getLatitude();
            double longitude = mLastLocation.getLongitude();
            tvLocation.setText(latitude + ", " + longitude);

        } else {

            tvLocation.setText("(Couldn't get the location. Make sure location is enabled on the device)");
        }
    }

    private boolean checkPlayServices(){
        int resultCode = GooglePlayServicesUtil.isGooglePlayServicesAvailable(this);
        if(resultCode != ConnectionResult.SUCCESS){
            if(GooglePlayServicesUtil.isUserRecoverableError(resultCode)){
                GooglePlayServicesUtil.getErrorDialog(resultCode,this,PLAY_SERVICES_RESOLUTION_REQUEST).show();
            }else{
                Toast.makeText(getApplicationContext(),"This device is not supported",Toast.LENGTH_LONG).show();
                finish();
            }
            return false;
        }
        return true;
    }

    protected synchronized void buildApiClient() {
        if (mGoogleApiClient == null) {
            mGoogleApiClient = new GoogleApiClient.Builder(this)
                    .addConnectionCallbacks(this)
                    .addOnConnectionFailedListener(this)
                    .addApi(LocationServices.API).build();
        }
    }

    @Override
    protected void onStart() {
        super.onStart();
        if (mGoogleApiClient != null) {
            mGoogleApiClient.connect();
        }
    }

    @Override
    protected void onResume() {
        super.onResume();

        checkPlayServices();

    }






    /**
     * Google api callback methods
     */
    @Override
    public void onConnectionFailed(ConnectionResult result) {
        Log.i(TAG, "Connection failed: ConnectionResult.getErrorCode() = "
                + result.getErrorCode());
    }

    @Override
    public void onConnected(Bundle arg0) {

        // Once connected with google api, get the location
        displayLocation();

    }

    @Override
    public void onConnectionSuspended(int arg0) {
        mGoogleApiClient.connect();
    }


}

Answer 1

因为mGoogleApiClient为空。

永远不会调用

buildApiClient（）方法，可能你在onCreate中犯了错误

 boolean checkPlayServices = false;
 if(checkPlayServices){
     buildApiClient();
 }

<强>阐述

此checkPlayServices变量此处为false，因此它不会调用buildApiClient（）方法，因此mGoogleApiClient为null。

@Override
protected void onCreate(Bundle savedInstanceState) {
    ...
    boolean checkPlayServices = false;
    if(checkPlayServices){
        buildApiClient();
    }
}

不调用connect方法，因为mGoogleApiClient为null

@Override
protected void onStart() {
    super.onStart();
    if (mGoogleApiClient != null) {
        mGoogleApiClient.connect();
    }
}

创建活动后，当您调用displayLocation（）方法时，由于mGoogleApiClient为空，它会崩溃

private void displayLocation() {
     //buildApiClient();
    mLastLocation = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);
    ...
}

致命异常：java.lang.IllegalArgumentException：需要GoogleApiClient参数

1 个答案: