android - 如何在 sharedpreferences 中保存一些值并在下一个 Activity 中获取它

Question

我正在创建一个测验应用程序，我提出了一些问题并以单选按钮的形式给出了选项，现在我想在 SharedPreferences 中存储答案的值(正确答案加上，错误答案减去) 并在其他 Activity 中显示该结果。我搜索并找到了这个 answer here

我使用了它，但仍然无法获得我想要的结果我的代码看起来像:

在 SharedPreferences 中保存一些值的主 Activity :

public class MainActivity extends Activity {
private SharedPreferences saveScore;
private SharedPreferences.Editor editor;
RadioGroup group;
RadioButton radioButton;    
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);     
    group = (RadioGroup) findViewById(R.id.radioGroup1);
    radioButton = (RadioButton) group.findViewById(group.getCheckedRadioButtonId());
    saveScore = getPreferences(MODE_PRIVATE);       
}
public void gotoNextAndSaveScore(View view) {
    if(group.getCheckedRadioButtonId() != R.id.radio3){
        editor = saveScore.edit();
        editor.putInt("score", -1);
        editor.commit();
    }else{
        editor = saveScore.edit();
        editor.putInt("score", 1);
        editor.commit();
    }       
    Intent intent = new Intent (MainActivity.this, NextActivity.class);
    startActivity(intent);
}}

这是尝试从 SharedPreferences 获取值的 Next Activity:

public class NextActivity extends Activity{

private SharedPreferences preferences;

@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_next);

    preferences = this.getSharedPreferences("score", MODE_WORLD_WRITEABLE);

    int value = preferences.getInt("score", 0);
    String score = "Your Score is : " + value;
    UIHelper.displayScore(this, R.id.tvScore, score );

}}

有人知道怎么做吗？

Answer 1

你应该换行

 saveScore = getPreferences(MODE_PRIVATE);      

到

saveScore =  getSharedPreferences("score",Context.MODE_PRIVATE);