Question

我想从sharedPreferences中删除我在listView中选择的项目。但我不知道如何将它包含在我的代码中。我已经尝试过很多我从互联网上看过的代码，但这会让我的应用程序出错。有人可以给我一个想法吗？大帮助。谢谢

这是MySharedPreference类：

public class MySharedPreference {
    private SharedPreferences pref;
    private SharedPreferences.Editor editor;
    // Context
    private Context _context;

    // Shared pref mode
    int PRIVATE_MODE = 0;

    // Sharedpref file name
    private static final String PREF_NAME = "pref";
    private static final String SCORES = "scores";

    public MySharedPreference(Context context) {
        this._context = context;
        pref = _context.getSharedPreferences(PREF_NAME, PRIVATE_MODE);
        editor = pref.edit();
    }

    public void saveHighScoreList(String scoreString) {
        editor.putString(PREF_NAME, scoreString);
        editor.commit();
    }

    public String getHighScoreList() {
        return pref.getString(PREF_NAME, "");
    }

}

这是我的ListViewAdapter：

public class ListViewAdapter_History extends ArrayAdapter<Input> {

    private Activity activity;

    public ListViewAdapter_History(Activity activity, int resource, List<Input> scores) {
        super(activity, resource, scores);
        this.activity = activity;

    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {

        ViewHolder holder = null;
        LayoutInflater inflater = (LayoutInflater) activity
                .getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
        // If holder not exist then locate all view from UI file.
        if (convertView == null) {
            // inflate UI from XML file
            convertView = inflater.inflate(R.layout.item_listview, parent, false);
            // get all UI view
            holder = new ViewHolder(convertView);
            // set tag for holder
            convertView.setTag(holder);
        } else {
            // if holder created, get tag from view
            holder = (ViewHolder) convertView.getTag();
        }

        Input score = getItem(position);

        holder.score.setText(score.getScore());

        return convertView;
    }

    private static class ViewHolder {

        private TextView score;

        public ViewHolder(View v) {

            score = (TextView) v.findViewById(R.id.score);
        }
    }
}

我希望它执行删除共享首选项到我的另一个类，其中删除按钮是，但我仍然在想我将选择onItemLongClick或一个简单的删除按钮。

PS。我希望你明白我想要达到的目标。感谢

Answer 1

您必须在适配器中实例化MySharedPreference类并在MySharedPreference类中创建一个删除方法：

public void deletePrefs(String score){
    editor.remove(score);
}

并在您的适配器中：

convertView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
            String s=getItem(position).getScore().getText().toString();
                presfs.deletePrefs(s)
            }
        });

如何在android studio中使用共享首选项删除listview中的特定数据？

1 个答案: