整数共享偏好始终 returns 0

Question

我正在尝试编写一个简单的密码检查代码来保护我的应用程序的设置。密码应保存在共享首选项中。当 sharedPreference returns 为零时，主要调用 setPassword。这是为了确保在有人第一次尝试进入设置时设置密码。然后 setPassword 应该设置一个密码并将其保存在 sharedPreference 中。但是当检查是否设置了密码时，sharedPreference 总是返回 0。

这是我的主要内容：

final Intent intentSetPasswords = new Intent(this, SetPasswordActivity.class);
    final SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);
    passwordToCheck = sharedPreferences.getInt("PASSWORDSETTINGS", 0);

    //setting button on click listener
    buttonSetings.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            //check if a password was set muss Überarbeitet werden
            passwordToCheck = sharedPreferences.getInt("PASSWORDSETTINGS", 0);
            Log.e("password", ""+ passwordToCheck);
            if(passwordToCheck==0){
                startActivity(intentSetPasswords);
            }else{
                startActivity(new Intent(MainActivity.this, PasswordCheckActivity.class));
            }
        }
    });

这是我的设置密码：

@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_set_password);

    final Intent intentSettings = new Intent(this, SettingsActivity.class);


    buttonSetPassword = (Button)findViewById(R.id.buttonSetPassword);
    textViewSetPassword = (TextView)findViewById(R.id.textViewSetPasswordText);
    editTextPassword = (EditText)findViewById(R.id.passwordNumericSettingsSetPassword);
    final Intent intent = new Intent(this, MainActivity.class);
    buttonSetPassword.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            counterButton++;
            switch (counterButton){
                case 1:
                    password = editTextPassword.getText().toString();
                    if (password.length() == 4){
                        Log.d("First Password", "taken");
                        buttonSetPassword.setText("Confirm Password!");
                        editTextPassword.setText("");
                    }else{
                        Log.d("First Password", "not taken");
                        textViewSetPassword.setText("The Password must be\nfour numbers long!");
                        password = "";
                        editTextPassword.setText("");
                        counterButton=0;
                    }
                    break;
                case 2:
                    passwordToConfirm = editTextPassword.getText().toString();
                    if (Integer.parseInt(passwordToConfirm)  == Integer.parseInt(password)){

                        Log.e("password", password);
                        Log.e("passwordToConfirm", passwordToConfirm);
                        SharedPreferences sharedPreferences = getSharedPreferences("PASSWORDS", 0);
                        SharedPreferences.Editor editor = sharedPreferences.edit();
                        editor.putInt("PASSWORDSETTINGS", Integer.parseInt(password));
                        editor.commit();
                        startActivity(intentSettings);
                        finish();
                    }else{
                        textViewSetPassword.setText("The passwords aren't the same!\nTry again!");
                        buttonSetPassword.setText("Set Password");
                        editTextPassword.setText("");
                        passwordToConfirm = "";
                        password = "";
                        counterButton = 0;
                        startActivity(intent);
                    }
                    break;
            }
        }
    });
}

我猜 sharedPreference 有问题，但我不明白是什么。

Answer 1

首先你会得到这样的共享偏好

final SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);

稍后设置密码时如下所示

SharedPreferences sharedPreferences = getSharedPreferences("PASSWORDS", 0);

它们是两个不同的共享首选项。使用第一个共享首选项。有关详细信息，请参阅此页面 https://developer.android.com/training/data-storage/shared-preferences

Answer 2

使用下面的库轻松管理数据

https://github.com/orhanobut/hawk

Answer 3

首先，检查counterButton值并确保case 2 branch被执行。其次，用于设置的 sharedPreferences 和用于获取的 sharedPreferences 应该相同。你可以这样做：

private final static String MyPREFERENCES = "MyPrefs"; //define two class fields
private SharedPreferences mSharedPreferences;

mSharedPreferences = getSharedPreferences(MyPREFERENCES, Context.MODE_PRIVATE);//in activity Oncreate() methods. 


//and set or get in other place as you want.

整数共享偏好始终 returns 0

Integer Shared preference allways returns 0

passwords

android

sharedpreferences