如何在需要启用GPS时构造代码

Question

如果启用了GPS，我的代码可以正常工作，但当需要启用时，它会强制崩溃。与未启用GPS时尝试获取位置有关。我试图为用户打开设置以启用GPS，但它只是继续尝试记录GPS（因此强制崩溃）。

我不知道何时何地给梅恩打电话。

第一个StartupSettings被称为：

public class StartupSettings extends Activity{
    boolean hasGps = false;
    @Override
    protected void onCreate(Bundle savedInstanceState){
        super.onCreate(savedInstanceState);
        setContentView(R.layout.startup_dialog);
        checkGPS();
    }
    public void checkGPS()
    {
        LocationHandler2 lh = new LocationHandler2();
        hasGps = lh.enableGPS(this);

        if (hasGps == true)
        {
            TextView tv = (TextView) findViewById(R.id.checkGPSConnection);
            tv.setTextColor(Color.GREEN);
        }

    }

上面的StartUpSettings() Activity调用的enableGPS()方法：

public class LocationHandler2{
    LocationManager mlocManager;
    public boolean enableGPS(final StartupSettings main)
    {    
        mlocManager = (LocationManager)main.getSystemService(Context.LOCATION_SERVICE);
        if(!mlocManager.isProviderEnabled(LocationManager.GPS_PROVIDER)) {
            //Ask the user to enable GPS
            AlertDialog.Builder builder = new AlertDialog.Builder(main);
            builder.setTitle("Location Manager");
            builder.setMessage("Would you like to enable GPS?");
            builder.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {
                    //Launch settings, allowing user to make a change
                    Intent i = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
                    main.startActivity(i);
                }
            });
            builder.setNegativeButton("No", new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {
                    //No location service, no Activity
                    main.finish();
                }
            });
            builder.create().show();
        }   
        else
        {
            return true;
        }
        return true;
    }

然后我想调用Main，它启动一个名为StartProcess() 的AsyncTask

public class Main extends Activity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.pages);

        StartProcess sProcess = new StartProcess();
        sProcess.execute(this);
    }  

StartProcess AsyncTask:

public class StartProcess extends AsyncTask<Main, Void, Void>
{
    @Override
    protected Void doInBackground(Main... params) {

        LocationHandler2 lh = new LocationHandler2();
        try {
            lh.getLocationStartEnd(params[0],0);
        } 
        catch (InterruptedException e) {
            e.printStackTrace();
        }
        return null;
    }

}

Logcat:

02-26 17:33:31.264: E/AndroidRuntime(10560): FATAL EXCEPTION: AsyncTask #1
02-26 17:33:31.264: E/AndroidRuntime(10560): java.lang.RuntimeException: An error occured while executing doInBackground()
02-26 17:33:31.264: E/AndroidRuntime(10560):    at android.os.AsyncTask$3.done(AsyncTask.java:200)
02-26 17:33:31.264: E/AndroidRuntime(10560):    at java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:273)
02-26 17:33:31.264: E/AndroidRuntime(10560):    at java.util.concurrent.FutureTask.setException(FutureTask.java:124)
02-26 17:33:31.264: E/AndroidRuntime(10560):    at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:307)
02-26 17:33:31.264: E/AndroidRuntime(10560):    at java.util.concurrent.FutureTask.run(FutureTask.java:137)
02-26 17:33:31.264: E/AndroidRuntime(10560):    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1068)
02-26 17:33:31.264: E/AndroidRuntime(10560):    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:561)
02-26 17:33:31.264: E/AndroidRuntime(10560):    at java.lang.Thread.run(Thread.java:1096)
02-26 17:33:31.264: E/AndroidRuntime(10560): Caused by: java.lang.IllegalArgumentException: provider==null
02-26 17:33:31.264: E/AndroidRuntime(10560):    at android.location.LocationManager.requestLocationUpdates(LocationManager.java:653)
02-26 17:33:31.264: E/AndroidRuntime(10560):    at mfc.generalguixapi8.LocationHandler2.getLocationStartEnd(LocationHandler2.java:120)
02-26 17:33:31.264: E/AndroidRuntime(10560):    at mfc.generalguixapi8.StartProcess.doInBackground(StartProcess.java:13)
02-26 17:33:31.264: E/AndroidRuntime(10560):    at mfc.generalguixapi8.StartProcess.doInBackground(StartProcess.java:1)
02-26 17:33:31.264: E/AndroidRuntime(10560):    at android.os.AsyncTask$2.call(AsyncTask.java:185)
02-26 17:33:31.264: E/AndroidRuntime(10560):    at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
02-26 17:33:31.264: E/AndroidRuntime(10560):    ... 4 more
02-26 17:34:37.694: E/global(10620): Deprecated Thread methods are not supported.
02-26 17:34:37.694: E/global(10620): java.lang.UnsupportedOperationException
02-26 17:34:37.694: E/global(10620):    at java.lang.VMThread.stop(VMThread.java:85)
02-26 17:34:37.694: E/global(10620):    at java.lang.Thread.stop(Thread.java:1379)
02-26 17:34:37.694: E/global(10620):    at java.lang.Thread.stop(Thread.java:1344)
02-26 17:34:37.694: E/global(10620):    at mfc.generalguixapi8.SplashScreen$1.run(SplashScreen.java:36)
02-26 17:36:18.134: E/global(10713): Deprecated Thread methods are not supported.
02-26 17:36:18.134: E/global(10713): java.lang.UnsupportedOperationException
02-26 17:36:18.134: E/global(10713):    at java.lang.VMThread.stop(VMThread.java:85)
02-26 17:36:18.134: E/global(10713):    at java.lang.Thread.stop(Thread.java:1379)
02-26 17:36:18.134: E/global(10713):    at java.lang.Thread.stop(Thread.java:1344)
02-26 17:36:18.134: E/global(10713):    at mfc.generalguixapi8.SplashScreen$1.run(SplashScreen.java:36)

Answer 1

小姐，我不知道你的问题是什么，但对于GPS，我做了这些教程http://thenewboston.org/list.php?cat=6它运行良好，不会崩溃。对于我不知道具体是哪一个的教程，它们应该是100多一点。你必须找到GPS的教程，这是30分钟的教程要做。我希望这是吗？

Answer 2

我最终将enableGPS()方法移动到我的StartupSettings活动，然后在用户启用GPS时使用startActivityForResult()启动Main。

不确定这是否理想，但已解决！