Android的檢查如果登錄

Question

我試圖做一個簡單的方法來檢查用戶的保存的登錄憑據是正確的......到目前爲止，我有：

public boolean checkLogin() { 
     final SharedPreferences prefs = this.getSharedPreferences(AndroidGPSTrackingActivity.class.getSimpleName(), 
       this.MODE_PRIVATE); 
     String userName = prefs.getString("userName", ""); 
     if (userName.isEmpty()) { 
      Log.i("UserName", "UserName not found."); 
      return false; 
     } 

     String password = prefs.getString("password", ""); 
     if (password.isEmpty()) { 
      Log.i("Password", "Password not found."); 
      return false; 
     } 


     mCheckTask = new CheckSavedLogin(userName, password, this); 
     mCheckTask.execute((Void) null); 


     return mCheckTask.execute((Void) null);//make this return true/false 
    } 

也：

public class CheckSavedLogin extends AsyncTask<Void, Void, Boolean> { 

     public final String mUserName; 
     public final String mPassword; 
     public boolean success; 
     public Context context; 

     CheckSavedLogin(String userName, String password, Context context) { 
      mUserName = userName; 
      mPassword = password; 
      this.context = context.getApplicationContext(); 
     } 

     protected Boolean doInBackground(Void... params) { 
      try { 
       HttpClient httpclient = new DefaultHttpClient(); 
       HttpPost httppost = new HttpPost("http://173.242.94.66/scripts/appLogin.php"); 

       List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(2); 
       nameValuePairs.add(new BasicNameValuePair("userName", mUserName)); 
       nameValuePairs.add(new BasicNameValuePair("password", mPassword)); 
       httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs)); 

       HttpResponse response = httpclient.execute(httppost); 
       String responseStr = EntityUtils.toString(response.getEntity()); 

       JSONObject json = new JSONObject(responseStr); 
       success = json.getBoolean("success"); 

       Log.d("Response", responseStr); 
      } catch (ClientProtocolException e) { 
       e.printStackTrace(); 
      } catch (UnsupportedEncodingException e) { 
       e.printStackTrace(); 
      } catch (IOException e) { 
       e.printStackTrace(); 
      } catch (JSONException e) { 
       e.printStackTrace(); 
      } 
      return success; 
     } 

     @Override 
     protected void onPostExecute(final Boolean success) { 
      mAuthTask = null; 
      showProgress(false); 

      if (success) { 
       storeLoginDetails(mUserName, mPassword); 
       //RETURN TRUE HERE? 
      } 
     } 

     @Override 
     protected void onCancelled() { 
      mAuthTask = null; 
      showProgress(false); 
     } 
    } 

我只是不知道如何使這一切都返回「真」或「虛假」的基礎上的迴應

Answer 1

通常我會提供一個回調。

public interface LoginHandler 
{ 
    onLoginComplete(boolean didLogIn); 
} 

然後我會在執行前在AsyncTask中註冊處理程序。

asyncTask.setHandler(new MyLoginHandler()); 
asyncTask.execute(0); 

然後在觸發時返回調用活動時，可以通過處理程序檢索結果。

public class MyLoginHandler implements LoginHandler 
{ 
    public void onLoginComplete(boolean didLogIn) 
    { 
     //Do what you want with didLogIn 
    } 
}