Disabling the Touch of an Activity

On a button click we are creating the same class as a dialog so that the touch is not received

public class MainActivity extends Activity {
    Dialog overlayDialog;
    EditText edt;
    Button bt;

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

        edt=(EditText)findViewById(R.id.editText1);
        bt=(Button)findViewById(R.id.button1);
        bt.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View arg0) {
            // TODO Auto-generated method stub
          disableAnyInput(); 
            }
        });
      }
    public void disableAnyInput(){
        Toast.makeText(getApplicationContext(), "This will disable any input. Click the backbutton " 
                                                    +  "to enable any input.", Toast.LENGTH_LONG).show();
       overlayDialog = new Dialog(MainActivity.this,android.R.style.Theme_Panel);
       overlayDialog.setCancelable(true);
       overlayDialog.show();
        } }