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// on bottom of onCreate add listener
mInterstitialAd .setAdListener(new AdListener(){
     public void onAdLoaded(){
          interstitial.show();
     }
});

} // end onCreate

 public void displayInterstitial (){
        if (mInterstitialAd.isLoaded()) {
            mInterstitialAd.show();
        }
    }

public class MainActivity extends Activity {
TextView txtV;
	Context cntx;
	
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        txtV = (TextView)findViewById(R.id.idLabel);
        cntx = this;
        try {
			StringBuilder strBuilder = myFunction(cntx);
			txtV.setText(strBuilder);
		} catch (IOException e) {
			e.printStackTrace();
		}

        
    }
    
    
    private StringBuilder myFunction(Context context) throws IOException {
        final Resources resources =  context.getResources();
        InputStream inputStream = resources.openRawResource(R.raw.my_file);
        BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
        StringBuilder strBuild = new StringBuilder();
        try {
            String line;
            while ((line = reader.readLine()) != null) {
            	strBuild.append(line);
            }
        } finally {
            reader.close();
        }
       return strBuild; 
       
    }
}

// Context instead Activity as a parameter
@Override
public void onAttach(Context context) {
    super.onAttach(context);

    Activity a;

    if (context instanceof Activity){
        a=(Activity) context;
    }

}

OnNoteClickedListener listener;
/* old emxample of usage
	@Override
	public void onAttach(Activity activity) {
		super.onAttach(activity);
		try {
			listener = (OnNoteClickedListener) activity;
		} catch (ClassCastException e) {
			throw new ClassCastException(activity.toString()
					+ " must implement OnNoteClickedListener");
		}
	}
*/
// new version of code
	@Override
	public void onAttach(Context context) {
		super.onAttach(context);

		Activity a;

		if (context instanceof Activity){
			a=(Activity) context;
			try {
				listener = (OnNoteClickedListener) a;
			} catch (ClassCastException e) {
				throw new ClassCastException(a.toString()
						+ " must implement OnNoteClickedListener");
			}
		}

	}

    private SensorManager mSensorManager;
    private PowerManager mPowerManager;
    private WindowManager mWindowManager;
    private Display mDisplay;

// onCreate
   @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

       // Get an instance of the SensorManager
        mSensorManager = (SensorManager) getSystemService(SENSOR_SERVICE);

        // Get an instance of the PowerManager
        mPowerManager = (PowerManager) getSystemService(POWER_SERVICE);

        // Get an instance of the WindowManager
        mWindowManager = (WindowManager) getSystemService(WINDOW_SERVICE);
        mDisplay = mWindowManager.getDefaultDisplay();

        setContentView(R.layout.main); // main.xml or your xml file name

}

Context context = getApplicationContext();
String DB_PATH = "/data/data/"
                + context.getPackageName()
                + "/databases/";