android - onReceive 発行は SMS を使用します

Question

Android プログラミングは初めてで、Broadcast Receivers の onReceive() メソッドに関する問題が発生しました。TurnGPSOnOff() のメソッドを持つ MainActivity.java である他のクラスから特定のメソッドを実行したいと考えています。システムが共有設定に保存されている値と等しい SMS を受信するたびに、GPS が無効になっている場合はオンになり、その逆も同様です。

MainActivity.java:

package com.smscontrol;

import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.provider.Settings;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class MainActivity extends Activity {

EditText editText1, editText2;
Button buttonSaveMem1;

 @Override

/** Called when the activity is first created. */
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

       editText1 = (EditText)findViewById(R.id.editText1);
       editText2 = (EditText)findViewById(R.id.EditText01);
       buttonSaveMem1 = (Button)findViewById(R.id.button1);

       buttonSaveMem1.setOnClickListener(buttonSaveMem1OnClickListener);

       LoadPreferences();
 }

   Button.OnClickListener buttonSaveMem1OnClickListener = new Button.OnClickListener(){

  @Override
  public void onClick(View arg0) {
   // TODO Auto-generated method stub
   SavePreferences("loc_key", editText1.getText().toString());
   SavePreferences("gps_key", editText2.getText().toString());
   Toast.makeText(getBaseContext(), "Keywords Saved.", Toast.LENGTH_SHORT).show();
   LoadPreferences();
  }

   };
   private void SavePreferences(String key, String value){
       Context context = getApplicationContext();
          AppPrefs appPrefs = new AppPrefs(context);
          appPrefs.setLoc_key(editText1.getText().toString());
          appPrefs.setGPS_key(editText2.getText().toString());
       }

       private void LoadPreferences(){
        Context context = getApplicationContext();
        AppPrefs appPrefs = new AppPrefs(context);
        String strSavedMem1 = appPrefs.getLoc_key();
        String strSavedMem2 = appPrefs.getGPS_key();
        editText1.setText(strSavedMem1);
        editText2.setText(strSavedMem2);
       }
       public void turnGPSOnOff(){

            String provider = Settings.Secure.getString(getContentResolver(), Settings.Secure.LOCATION_PROVIDERS_ALLOWED);
            if(!provider.contains("gps"))
            { //if gps is disabled
                final Intent poke = new Intent();
                poke.setClassName("com.android.settings", "com.android.settings.widget.SettingsAppWidgetProvider"); 
                poke.addCategory(Intent.CATEGORY_ALTERNATIVE);
                poke.setData(Uri.parse("3")); 
                sendBroadcast(poke);
            } 
            else { //if gps is enabled
                final Intent poke = new Intent();
                poke.setClassName("com.android.settings", "com.android.settings.widget.SettingsAppWidgetProvider");
                poke.addCategory(Intent.CATEGORY_ALTERNATIVE);
                poke.setData(Uri.parse("3")); 
                sendBroadcast(poke);    
        }

       }       
}

AppPrefs.java:

package com.smscontrol;

import android.app.Activity;
import android.content.Context;
import android.content.SharedPreferences;

public class AppPrefs {

private static final String KEYWORDS = "KEYWORDS";
private SharedPreferences appSharedPrefs;
private SharedPreferences.Editor prefsEditor;
private String gps_key = "gps_key_prefs";
private String loc_key = "loc_key_prefs";

public AppPrefs(Context context){
    this.appSharedPrefs = context.getSharedPreferences(KEYWORDS, Activity.MODE_PRIVATE);
    this.prefsEditor = appSharedPrefs.edit();
    }

public String getGPS_key() {
    return appSharedPrefs.getString(gps_key, null);
    }

public void setGPS_key(String _gps_key) {
    prefsEditor.putString(gps_key, _gps_key).commit();
    }

public String getLoc_key() {
    return appSharedPrefs.getString(loc_key, null);
    }

public void setLoc_key(String _loc_key) {
    prefsEditor.putString(loc_key, _loc_key).commit();
    }

}

SmsListener.java:

package com.smscontrol;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.telephony.SmsMessage;
import android.widget.Toast;


public class SmsListener extends BroadcastReceiver {
    MainActivity Activity = new MainActivity();
    @Override
    public void onReceive(Context context, Intent intent) {
        // TODO Auto-generated method stub



    AppPrefs appPrefs = new AppPrefs(context);
    String strSavedMem1 = appPrefs.getLoc_key();
    String strSavedMem2 = appPrefs.getGPS_key();

    if(intent.getAction().equals("android.provider.Telephony.SMS_RECEIVED")){

        Bundle bundle = intent.getExtras();           //---get the SMS message passed in---
        SmsMessage[] msgs = null;

        String str = "";

        if (bundle != null){
            //---retrieve the SMS message received---
            try{
                Object[] pdus = (Object[]) bundle.get("pdus");
                msgs = new SmsMessage[pdus.length];
                for(int i=0; i<msgs.length; i++){
                    msgs[i] = SmsMessage.createFromPdu((byte[])pdus[i]);
                    str = msgs[i].getMessageBody().toString();

                    if (str.equals(strSavedMem1)){
                        Toast.makeText(context, "LOCATE", Toast.LENGTH_SHORT).show();
                    } else if (str.equals(strSavedMem2)){ 
                         Toast.makeText(context, "GPS", Toast.LENGTH_SHORT).show();
                    }
                }
            }catch(Exception e){
//                            Log.d("Exception caught",e.getMessage());
            }

        }
    }
}

}

どんなアドバイスや助けもします。私の論文の一部にひどく必要でした。ありがとう！