java基于用户输入在Android中编辑SharedReference

Question

我对Java/Android开发非常陌生，我试图让用户检查单选按钮中的“男孩”或“女孩”，并将其写入SharedPreferences，以便我可以在其他活动中使用它。每当我尝试打开此活动时，我的应用程序就会崩溃

public class NewBabyProfile extends Activity {

String GENDER = "Baby1Gender"; 

// SharedPreferences initializations
SharedPreferences babyOneGender = getSharedPreferences(getString(R.string.baby_one_profile), Context.MODE_PRIVATE);
SharedPreferences.Editor editor = babyOneGender.edit();

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

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.new_baby_profile, menu);
    return true;
}

public void onRadioButtonClicked(View genderSelection){
    boolean checked = ((RadioButton) genderSelection).isChecked();

    switch(genderSelection.getId()) {
        case R.id.gender_boy:
            if (checked)
                editor.putString("gender","boy").commit();
            break;

        case R.id.gender_girl:
            if (checked)
                editor.putString("gender","girl").commit();
            break;

    }
}

}

Answer 1

不能在一个类中直接初始化以下两个

SharedPreferences babyOneGender = getSharedPreferences(getString(R.string.baby_one_profile), Context.MODE_PRIVATE);
SharedPreferences.Editor editor = babyOneGender.edit();

SharedReferences初始化应该在onCreate（）或onResume（）之类的方法中进行 将其移动到onCreate（Bundle）中，你的应用程序将不会再次崩溃。另外，请查看日志，自己找出问题：）

最终代码：-

public class NewBabyProfile extends Activity {

String GENDER = "Baby1Gender"; 

//Global declaration.
SharedPreferences babyOneGender;
SharedPreferences.Editor editor;


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

    //Initializations inside onCreate() so no error.

    babyOneGender = getSharedPreferences(getString(R.string.baby_one_profile), Context.MODE_PRIVATE);
    editor = babyOneGender.edit();


}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.new_baby_profile, menu);
    return true;
}

public void onRadioButtonClicked(View genderSelection){
    boolean checked = ((RadioButton) genderSelection).isChecked();

    switch(genderSelection.getId()) {
        case R.id.gender_boy:
            if (checked)
                editor.putString("gender","boy").commit();
            break;

        case R.id.gender_girl:
            if (checked)
                editor.putString("gender","girl").commit();
            break;

    }
}

}

Answer 2

移动BabyNegender&；要重新创建的编辑器：

    SharedPreferences babyOneGender;
    SharedPreferences.Editor editor;

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

        babyOneGender = getSharedPreferences(getString(R.string.baby_one_profile), Context.MODE_PRIVATE);
        editor = babyOneGender.edit();

Answer 3

试试这个

SharedPreferences babyOneGender = getApplication().getSharedPreferences(getString(R.string.baby_one_profile), Context.MODE_PRIVATE);