private Button login;// 登录按钮 private CheckBox rememberPsdBox, autoLoginBox;// 记住密码、自动登陆复选框 private EditText name, psd;// 用户名和密码 private TextView userInfo; SharedPreferences loginPreferences, accessPreferences;// 保存登陆信息和访问次数 SharedPreferences.Editor loginEditor, accessEditor;// 对应的编辑器 String userName; String userPsd; boolean isSavePsd,isAutoLogin; public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); loginPreferences = this.getSharedPreferences("login", Context.MODE_PRIVATE); //补充完整-1：采用参数"access"和Context.MODE_PRIVATE，实例化accessPreferences对象 int count=accessPreferences.getInt("count",1); Toast.makeText(MainActivity.this,"欢迎您，这是第"+count+"次访问！", Toast.LENGTH_LONG).show(); loginEditor = loginPreferences.edit(); //补充完整-2：从accessPreferences中，实例化accessEditor编辑器 accessEditor.putInt("count",++count); accessEditor.commit(); //提交 userName = loginPreferences.getString("name", null); userPsd = loginPreferences.getString("psd", null); isSavePsd=loginPreferences.getBoolean("isSavePsd",false); isAutoLogin=loginPreferences.getBoolean("isAutoLogin", false); if (isAutoLogin) { this.setContentView(R.layout.activity_welcome); userInfo = (TextView) findViewById(R.id.userInfo); userInfo.setText("欢迎您：" + userName + ",登陆成功！"); } else{ loadActivity(); } } public void loadActivity() { this.setContentView(R.layout.activity_main); login = (Button) findViewById(R.id.login); rememberPsdBox = (CheckBox) findViewById(R.id.rememberPsd); autoLoginBox = (CheckBox) findViewById(R.id.autoLogin); name = (EditText) findViewById(R.id.name); psd = (EditText) findViewById(R.id.psd); if (isSavePsd) { psd.setText(userPsd); name.setText(userName); rememberPsdBox.setChecked(true); } login.setOnClickListener(new OnClickListener() { public void onClick(View v) { loginEditor.putString("name", name.getText().toString()); loginEditor.putString("psd", psd.getText().toString()); loginEditor.putBoolean("isSavePsd", rememberPsdBox.isChecked()); loginEditor.putBoolean("isAutoLogin", autoLoginBox.isChecked()); //补充完整-3：loginEditor的commit方法提交数据 MainActivity.this.setContentView(R.layout.activity_welcome); userInfo = (TextView) findViewById(R.id.userInfo); userInfo.setText("欢迎您：" + name.getText().toString() + ",登陆成功！"); } }); }补充代码

根据代码，需要补充完整-1、完整-2和完整-3处的代码。

完整-1：

accessPreferences = this.getSharedPreferences("access", Context.MODE_PRIVATE);
accessEditor = accessPreferences.edit();

完整-2：

accessEditor = accessPreferences.edit();

完整-3：

loginEditor.commit();

补充完整后的代码如下：

private Button login;// 登录按钮
private CheckBox rememberPsdBox, autoLoginBox;// 记住密码、自动登陆复选框
private EditText name, psd;// 用户名和密码
private TextView userInfo;
SharedPreferences loginPreferences, accessPreferences;// 保存登陆信息和访问次数
SharedPreferences.Editor loginEditor, accessEditor;// 对应的编辑器
String userName;
String userPsd;
boolean isSavePsd, isAutoLogin;

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    loginPreferences = this.getSharedPreferences("login", Context.MODE_PRIVATE);
    accessPreferences = this.getSharedPreferences("access", Context.MODE_PRIVATE); // 补充完整-1：采用参数"access"和Context.MODE_PRIVATE，实例化accessPreferences对象
    int count = accessPreferences.getInt("count", 1);
    Toast.makeText(MainActivity.this, "欢迎您，这是第" + count + "次访问！", Toast.LENGTH_LONG).show();
    loginEditor = loginPreferences.edit();
    accessEditor = accessPreferences.edit(); // 补充完整-2：从accessPreferences中，实例化accessEditor编辑器
    userName = loginPreferences.getString("name", null);
    userPsd = loginPreferences.getString("psd", null);
    isSavePsd = loginPreferences.getBoolean("isSavePsd", false);
    isAutoLogin = loginPreferences.getBoolean("isAutoLogin", false);
    if (isAutoLogin) {
        this.setContentView(R.layout.activity_welcome);
        userInfo = (TextView) findViewById(R.id.userInfo);
        userInfo.setText("欢迎您：" + userName + ",登陆成功！");
    } else {
        loadActivity();
    }
}

public void loadActivity() {
    this.setContentView(R.layout.activity_main);
    login = (Button) findViewById(R.id.login);
    rememberPsdBox = (CheckBox) findViewById(R.id.rememberPsd);
    autoLoginBox = (CheckBox) findViewById(R.id.autoLogin);
    name = (EditText) findViewById(R.id.name);
    psd = (EditText) findViewById(R.id.psd);
    if (isSavePsd) {
        psd.setText(userPsd);
        name.setText(userName);
        rememberPsdBox.setChecked(true);
    }
    login.setOnClickListener(new OnClickListener() {
        public void onClick(View v) {
            loginEditor.putString("name", name.getText().toString());
            loginEditor.putString("psd", psd.getText().toString());
            loginEditor.putBoolean("isSavePsd", rememberPsdBox.isChecked());
            loginEditor.putBoolean("isAutoLogin", autoLoginBox.isChecked());
            accessEditor.putInt("count", ++count); // 补充完整-3：loginEditor的commit方法提交数据
            loginEditor.commit();
            MainActivity.this.setContentView(R.layout.activity_welcome);
            userInfo = (TextView) findViewById(R.id.userInfo);
            userInfo.setText("欢迎您：" + name.getText().toString() + ",登陆成功！");
        }
    });
}