java - 将动态数据存储到标签

Question

我正在尝试开发我的第一个应用程序，但我需要一些帮助。 因此，要访问我的应用程序，您必须登录并写下您自己的用户名和密码。 我的应用程序左侧有一个滑动菜单，我使用 jfeinstein10 库。 现在，我希望在此菜单的第一行中显示用户的用户名，以便您了解这是一个动态字符串。

这是我行的 .xml 代码:

<item name="list_item_municipio_id" type="slidingmenu" />
<item name="list_item_municipio_label" type="slidingmenu">&quot;Municipio&quot;</item>
<item name="list_item_municipio_icon " type="slidingmenu">"@drawable/iconamunicipio"</item>

现在用<item name="list_item_municipio_label" 显示“municipio” . 我读到字符串是静态的，并且可能的解决方案是使用 SharedPreferences。 你可以给我一个例子吗？因为我不明白如何将用户名存储到 SharedPreferences。 这是 login.java 的代码:

package com.baruckis.SlidingMenuImplementation;

import java.util.ArrayList;
import java.util.List;

import org.apache.http.NameValuePair;
import org.apache.http.message.BasicNameValuePair;
import org.json.JSONException;
import org.json.JSONObject;

import android.app.Activity;

import android.app.ProgressDialog;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;

import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class Login extends Activity implements OnClickListener{
public static final String PREFS_NAME = "LoginPrefs";
private EditText user, pass;
private Button mSubmit, mRegister;
private ProgressDialog pDialog;

// Attivo una connessione JSON
JSONParser jsonParser = new JSONParser();

//Collego un file php sul mio server
private static final String LOGIN_URL = "http://provasitosaronno.dnshosting.it/php/login.php";

//JSON gestisce le risposte fornite dallo script 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); 
    SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0);
    if (settings.getString("logged", "").toString().equals("logged")) {
        Intent i = new Intent(Login.this, SlidingMenuFromClassActivity.class);
        finish();
        startActivity(i);
    }

    //Imposto le due variabili user e pass
    user = (EditText)findViewById(R.id.username);
    pass = (EditText)findViewById(R.id.password);

    //Collego i due pulsanti del login e del register
    mSubmit = (Button)findViewById(R.id.login);
    mRegister = (Button)findViewById(R.id.register);

    //Aggiungo la funzione del clicklistener
    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> {

     /**
     * Before starting background thread Show Progress Dialog
     * */
    boolean failure = false;

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

    @Override
    protected String doInBackground(String... args) {
        // TODO Auto-generated method stub

        int success;
        String username = user.getText().toString();
        String password = pass.getText().toString();
        try {
            //Aggiungo i parametri generati dalle variabili
            List<NameValuePair> params = new ArrayList<NameValuePair>();
            params.add(new BasicNameValuePair("username", username));
            params.add(new BasicNameValuePair("password", password));

            Log.d("request!", "starting");
            // Ottengo i risultati dalla connessione http
            JSONObject json = jsonParser.makeHttpRequest(
                   LOGIN_URL, "POST", params);

            //Aspetto una risposta da JSON
            Log.d("Login attempt", json.toString());

            //Se il tutto avviene...
            success = json.getInt(TAG_SUCCESS);
            if (success == 1) {

                SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0);
                SharedPreferences.Editor editor = settings.edit();
                editor.putString("logged", "logged");
                editor.commit();

                Log.d("Login Successful!", json.toString());
                Intent i = new Intent(Login.this, SlidingMenuFromClassActivity.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;

    }
    /**
     * After completing background task Dismiss the progress dialog
     * **/
    protected void onPostExecute(String file_url) {
        //funzione dismiss
        pDialog.dismiss();
        if (file_url != null){
            Toast.makeText(Login.this, file_url, Toast.LENGTH_LONG).show();
        }

    }

}

Answer 1

下面是如何将信息保存到 SharedPreference 的代码。

SharedPreferences settings = this.getActivity().getSharedPreferences("MyApp", 0);
SharedPreferences.Editor editor = settings.edit();      
String user = "foobar";
editor.putString("user", user);
editor.commit();