我在asynctask中看不到进度对话框

Question

我尝试在完成后台工作进度停止后启动后台工作时显示进度对话框。对于后台工作，我使用了同步任务类，但未显示进度对话框。 下面是我的代码LoginActivity.java

public class LoginActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    setContentView(R.layout.activity_main);

    loginButton = (Button) findViewById(R.id.btn);
    txtUserId = (EditText) findViewById(R.id.username);
    txtPassword = (EditText) findViewById(R.id.password);
    forgot_pwd = (TextView) findViewById(R.id.forgot_password);
    tvError = (TextView) findViewById(R.id.tv_result);
    chkRem = (CheckBox) findViewById(R.id.chkRem);
    footer = (TextView) findViewById(R.id.footer_login);
    loginButton.setOnClickListener(new View.OnClickListener() {
    @Override
     public void onClick(View v) {
     if (txtUserId.getText().toString().length() == 0) {

                    return;
       }else if (txtPassword.getText().toString().length() == 0) {

                    return;
                }
       user = txtUserId.getText().toString();
       pwd = txtPassword.getText().toString();
       try {
       boolean con = isInternetConnected();
       Log.d("connection", "" + con);
       if (con) {
       AsyncTaskCommon atw = new AsyncTaskCommon(LoginActivity.this, user, pwd);
       stcode = atw.execute("DoLogin").get();
       /*int i = 0;
       while (!BaseActivity.baseResponse) {
       i++;
       }*/
       } else {}
       } catch (Exception e) {  }
       if (stcode.equals("0")) {
       BaseActivity.sMsg = "";
       finish();
       Intent m = new Intent(LoginActivity.this, HomePage.class);
       startActivity(m);
        } else {
      BaseActivity.toastValidationMessage(LoginActivity.this,BaseActivity.sMsg);
                }

            }
        }); 
      });
    }
}

AsynctaskcommonClass.java

public class AsyncTaskCommon extends AsyncTask<String, Void, String> {
    public AsyncTaskCommon(Context context){
    this.context = context;
    }
    public AsyncTaskCommon(Context context, String data, String data1)
    {
        this.context = context;
        AsyncTaskCommon.data = data;
        AsyncTaskCommon.data1 = data1;

    }
    public AsyncTaskCommon(Context context, String mobileno, String smspwd, String emailId)
    {
        this.context = context;
        AsyncTaskCommon.mobileno = mobileno;
        AsyncTaskCommon.smspwd = smspwd;
        AsyncTaskCommon.emailId = emailId;
    }

    public AsyncTaskCommon(Context context, String fname, String firmname, String lname, String mobile, String email, String groupId, String patternId)
    {
        this.context = context;
        AsyncTaskCommon.fname = fname;
        firm = firmname;
        AsyncTaskCommon.email = email;
        AsyncTaskCommon.lname = lname;
        AsyncTaskCommon.mobile = mobile;
        AsyncTaskCommon.groupId = groupId;
        AsyncTaskCommon.patternId = patternId;
    }
    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        ba = new BaseActivity();
        BaseActivity.baseResponse = false;
        BaseActivity.baseStcode = "";
        BaseActivity.sMsg = "";
        pleaseWaitDialog = new ProgressDialog(c);
        pleaseWaitDialog.setMessage(c.getResources().getString(R.string.waitMsg));
        pleaseWaitDialog.setTitle(R.string.app_name);
        pleaseWaitDialog.setIndeterminate(true);
        pleaseWaitDialog.setIcon(R.drawable.bus1);
        pleaseWaitDialog.setProgressStyle(ProgressDialog.STYLE_SPINNER);
        pleaseWaitDialog.setCancelable(true);
        pleaseWaitDialog.show();
    }
    protected void onPostExecute(String resString) {
        super.onPostExecute(resString);
    if ((pleaseWaitDialog != null) && pleaseWaitDialog.isShowing()) {
            pleaseWaitDialog.dismiss();
            pleaseWaitDialog = null;
        }
    }
    @Override
    protected String doInBackground(String... params) {

     methodName = params[0];
     resStr = getLoginRequest(data, data1);

     List<NameValuePair> params2 = new ArrayList<NameValuePair>();
     params2.add(new BasicNameValuePair(BaseActivity.REQUESTATTR, resStr));
     resString = ba.sendData(params2,methodName);
     try {
     JSONObject jsonObject = new  JSONObject(resString.substring(resString.indexOf("{"), resString.lastIndexOf("}") + 1));
            Log.d("jsonObject", "" + jsonObject);
            JSONObject object = jsonObject.getJSONObject("MRRESP");
            stcode = object.getString("STCODE");
            stmsg = object.getString("STMSG");
            BaseActivity.sMsg = stmsg;
            BaseActivity.baseStcode = stcode;
            Log.d("base stcode in backg", "" + BaseActivity.baseStcode);

        }catch(Exception e)
        {
            e.printStackTrace();
        }
        BaseActivity.baseResponse = true;
        return stcode;
    }

    private String getLoginRequest(String UserId, String  password)
    {  

    }