0 
public class Login extends Activity implements OnClickListener {

    private EditText user, pass;
    private Button mSubmit, mRegister;

    // Progress Dialog
    private ProgressDialog pDialog;

    // JSON parser class
    JSONParser jsonParser = new JSONParser();


    private static final String LOGIN_URL = "http://192.168.2.4/mybringbacktutorial/login.php";


    private static final String TAG_SUCCESS = "success";
    private static final String TAG_MESSAGE = "message";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        setContentView(R.layout.login);

        // setup input fields
        user = (EditText) findViewById(R.id.username);
        pass = (EditText) findViewById(R.id.password);

        // setup buttons
        mSubmit = (Button) findViewById(R.id.login);
        mRegister = (Button) findViewById(R.id.register);

        // register listeners
        mSubmit.setOnClickListener(this);
        mRegister.setOnClickListener(this);


    }

    @Override
    public void onClick(View v) {
        // TODO Auto-generated method stub
        switch (v.getId()) {
        case R.id.login:
            new AttemptLogin().execute();
            break;
        case R.id.register:
            Intent i = new Intent(this, Register.class);
            startActivity(i);
            break;

        default:
            break;
        }
    }

    class AttemptLogin extends AsyncTask<String, String, String> {

        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            pDialog = new ProgressDialog(Login.this);
            pDialog.setMessage("Attempting login...");
            pDialog.setIndeterminate(false);
            pDialog.setCancelable(true);
            pDialog.show();
        }

        @Override
        protected String doInBackground(String... args) {
            // TODO Auto-generated method stub
            // Check for success tag
            int success;
            String username = user.getText().toString();
            String password = pass.getText().toString();
            try {
                // Building Parameters
                List<NameValuePair> params = new ArrayList<NameValuePair>();
                params.add(new BasicNameValuePair("username", username));
                params.add(new BasicNameValuePair("password", password));

                Log.d("request!", "starting");
                // getting product details by making HTTP request
                JSONObject json = jsonParser.makeHttpRequest(LOGIN_URL, "POST",
                        params);

                // check your log for json response
                Log.d("Login attempt", json.toString());

                // json success tag
                success = json.getInt(TAG_SUCCESS);
                if (success == 1) {
                    Log.d("Login Successful!", json.toString());
                    // save user data
                    SharedPreferences sp = PreferenceManager
                            .getDefaultSharedPreferences(Login.this);
                    Editor edit = sp.edit();
                    edit.putString("username", username);
                    edit.commit();

                    Intent i = new Intent(Login.this, ReadComments.class);
                    finish();
                    startActivity(i);
                    return json.getString(TAG_MESSAGE);
                } else {
                    Log.d("Login Failure!", json.getString(TAG_MESSAGE));
                    return json.getString(TAG_MESSAGE);
                }
            } catch (JSONException e) {
                e.printStackTrace();
            }

            return null;

        }

        @Override
        protected void onPostExecute(String file_url) {
            // dismiss the dialog once product deleted
            pDialog.dismiss();
            if (file_url != null) {
                Toast.makeText(Login.this, file_url, Toast.LENGTH_LONG).show();
            }

        }

    }

}

伙计们如何在这段代码中创建用户会话？我希望 ReadComments.class 有一个注销按钮，当用户按下后退按钮时，登录用户的会话不会被破坏，如果应用程序关闭，也不会破坏应用程序。再次打开用户的登录信息仍然存在。

4

2 回答 2

1

在你的 onDestory() 检查对话框是否显示，如果显示像这样关闭它..

@Override
protected void onDestroy() {
    if (pDialog != null) {
        if (pDialog.isShowing()) {
            pDialog.dismiss();
            pDialog = null;
        }
    }
    super.onDestroy();
}
于 2013-11-12T10:47:26.690 回答
0

在你doInBackground的AttemptLogin班级尝试pDialog.dismiss();在你打电话之前finish()添加if (success == 1)

于 2013-11-12T10:47:55.127 回答