Question

我正在尝试要求打开应用后启用位置服务。我相应地进行了编码，构建成功，但应用程序未打开，始终停止。我已经尝试过从我自己那里寻找错误，但是没有成功。我是android应用程序的新手，你们可以帮助我，我在这里做错了如何解决此问题吗？

代码

package com.abc.gpslauncher;

import android.content.Context;
import android.content.IntentSender;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;

import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.common.api.PendingResult;
import com.google.android.gms.common.api.ResultCallback;
import com.google.android.gms.common.api.Status;
import com.google.android.gms.location.LocationRequest;
import com.google.android.gms.location.LocationServices;
import com.google.android.gms.location.LocationSettingsRequest;
import com.google.android.gms.location.LocationSettingsResult;
import com.google.android.gms.location.LocationSettingsStatusCodes;
import com.google.android.gms.maps.OnMapReadyCallback;


public abstract class MainActivity extends AppCompatActivity implements GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener, LocationListener {
    Context context;
    String TAG;
    protected static final int REQUEST_CHECK_SETTINGS = 0x1;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        context = this;

        LocationManager manager = (LocationManager) getSystemService(Context.LOCATION_SERVICE );
        boolean statusOfGPS = manager.isProviderEnabled(LocationManager.GPS_PROVIDER);

        if(!statusOfGPS)
        {
            buildAlertMessageNoGps(context);
        }
    }

    private void buildAlertMessageNoGps(Context context)
    {

        GoogleApiClient googleApiClient = new GoogleApiClient.Builder(context)
                .addApi(LocationServices.API).build();
        googleApiClient.connect();

        LocationRequest locationRequest = LocationRequest.create();
        locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
        locationRequest.setInterval(10000);
        locationRequest.setFastestInterval(10000 / 2);

        LocationSettingsRequest.Builder builder = new LocationSettingsRequest.Builder().addLocationRequest(locationRequest);
        builder.setAlwaysShow(true);

        PendingResult<LocationSettingsResult> result = LocationServices.SettingsApi.checkLocationSettings(googleApiClient, builder.build());
        result.setResultCallback(new ResultCallback<LocationSettingsResult>() {
            @Override
            public void onResult(LocationSettingsResult result) {

                final Status status = result.getStatus();
                switch (status.getStatusCode()) {
                    case LocationSettingsStatusCodes.SUCCESS:
                        Log.i(TAG, "All location settings are satisfied.");
                        break;
                    case LocationSettingsStatusCodes.RESOLUTION_REQUIRED:
                        Log.i(TAG, "Location settings are not satisfied. Show the user a dialog to upgrade location settings ");
                        try {
                            status.startResolutionForResult(MainActivity.this, REQUEST_CHECK_SETTINGS);
                        } catch (IntentSender.SendIntentException e) {
                            Log.i(TAG, "PendingIntent unable to execute request.", e);
                        }
                        break;
                    case LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE:
                        Log.i(TAG, "Location settings are inadequate, and cannot be fixed here. Dialog not created.");
                        break;
                }
            }
        });
    }


}

Logcat

09-07 20:19:26.044 3779-3779/com.setu.gpslauncher E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.abc.gpslauncher, PID: 3779
java.lang.RuntimeException: Unable to instantiate activity
ComponentInfo{com.abc.gpslauncher/com.abc.gpslauncher.MainActivity}: 
java.lang.InstantiationException: 
java.lang.Class<com.abc.gpslauncher.MainActivity> cannot be instantiated

Answer 1

从您的班级中删除abstract关键字。

抽象类无法初始化，因此会出错。

并实现您的界面，GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener, LocationListener。

要求启用位置服务android应用未打开

1 个答案: