Android数据存储（2）——SharedPreferences

来源：互联网发布：外媒特朗普访华知乎编辑：程序博客网时间：2024/06/09 21:48

布局

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="vertical" >    <EditText        android:id="@+id/et_username"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:hint="UserName" />    <EditText        android:id="@+id/et_password"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:hint="Password"        android:inputType="textPassword" />    <Button        android:id="@+id/btn_login"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:text="login" />    <Button        android:id="@+id/btn_exit"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:text="exit" /></LinearLayout>

MainActivity.java

public class MainActivity extends Activity implements OnClickListener {    Button btn_login, btn_exit;    EditText et_username, et_password;    private String username = "zhangsan";    private String password = "123";    private SharedPreferences sp;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        init();    }    /*     * 初始化     */    private void init() {        btn_login = (Button) findViewById(R.id.btn_login);        btn_exit = (Button) findViewById(R.id.btn_exit);        et_username = (EditText) findViewById(R.id.et_username);        et_password = (EditText) findViewById(R.id.et_password);        btn_login.setOnClickListener(this);        btn_exit.setOnClickListener(this);        sp = getSharedPreferences("UserInfo", MODE_PRIVATE);        // 填充以保存的账号密码        et_username.setText(sp.getString("username", ""));        et_password.setText(sp.getString("password", ""));    }    /*     * 监听器     */    @Override    public void onClick(View v) {        switch (v.getId()) {        case R.id.btn_login:            String tUserName = et_username.getText() + "";            String tPassword = et_password.getText() + "";            Editor editor = sp.edit();            // String tPassword = et_password.getText().toString();            if (tUserName.equals(username) && tPassword.equals(password)) {                // 保存账号密码                editor.putString("username", tUserName);                editor.putString("password", tPassword);                editor.commit();                Toast.makeText(this, "已登录", Toast.LENGTH_SHORT).show();            } else {                et_username.setText("");                et_password.setText("");                // 清空密码                editor.putString("username", "");                editor.putString("password", "");                editor.commit();                Toast.makeText(this, "未登录，账号或密码错误！", Toast.LENGTH_SHORT).show();            }            break;        case R.id.btn_exit:            finish();            break;        }    }}

0 0