Java SharedReferences未保存

我一直在尝试保存一个名为“first”的布尔值，它表示自安装应用程序以来该活动是否已首次启动。布尔值“first”最初为true，但在活动使用一次后设置为false（即，在下一个活动开始之前，该值设置为false）。我曾尝试使用SharedReferences保存此布尔值，但每当我在杀死它后启动应用程序时，MainActivity仍会再次显示（如果“first”为false，则不应出现这种情况）

我的MainActivity.java如下所示-

protected final static String INTENT_KEY = "NAME";
private static final String PREFS_NAME = "SaveStates"; //The SharedPreferences file name.
private Boolean first = true; // Signifies whether the app started for the first time.
SharedPreferences settings;
SharedPreferences.Editor editor;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    settings = getSharedPreferences(PREFS_NAME, 0);
    editor = settings.edit();
    resetParam(); // Retrieving the boolean "first".
    // Start the next activity if the app has been started before.
    if (!first) {
        Intent intent = new Intent(this, DisplayMessageActivity.class);
        startActivity(intent);
    }
    setContentView(R.layout.activity_main);
}

/** Sends the name input by the user to the next activity */
public void sendMessage(View view) {
    Intent intent = new Intent(this, DisplayMessageActivity.class);
    EditText editText = (EditText) findViewById(R.id.edit_name);
    String name = editText.getText().toString();
    // Send name to next activity if it's not empty.
    if (!("".equals(name))) {
        setParam(); // SETTING AND SAVING "first" AS FALSE.
        intent.putExtra(INTENT_KEY, name);
        startActivity(intent);
    }
}

/** Saving the Boolean "first" in the SharedPreferences PREF_NAME file */
private void setParam() {
    // Saving the Boolean "first" in the SharedPreferences PREF_NAME file.
    editor.clear();
    editor.putBoolean("first", false);
    editor.commit();
}

/** Retrieving the Boolean "first" from the SharedPreferences PREF_NAME file */
private void resetParam() {
    first =  settings.getBoolean("first", true);
}

当我第一次使用应用程序时（即“first”为true），转到下一个活动（即“first”在下一个活动开始前设置为false），完全关闭应用程序并返回，为什么我要再次从Main活动开始？为什么“first”未在我的SharedReferences文件（PREFS\u NAME）中保存为false你做错了

请仔细看看

一、 就个人而言，使用：

使用此选项将值保存在

SharedReferences

中：

SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(this);
SharedPreferences.Editor editor = preferences.edit();
editor.putString("Name","Harneet");
editor.apply();

SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(this);
String name = preferences.getString("Name", "");
if(!name.equalsIgnoreCase(""))
{
    name = name + "  Sethi";  /* Edit the value here*/
}

使用此读取

SharedReferences

中的值：

SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(this);
SharedPreferences.Editor editor = preferences.edit();
editor.putString("Name","Harneet");
editor.apply();

SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(this);
String name = preferences.getString("Name", "");
if(!name.equalsIgnoreCase(""))
{
    name = name + "  Sethi";  /* Edit the value here*/
}