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我试图实现SharedPreference 以在我的适配器中存储复选框选中列表RecyclerView。我能够正确记录已检查的列表数组。但我无法将其保存到共享首选项并在每次重新打开应用程序时恢复它。

这是我的RecyclerView适配器代码。

public class HomeManager extends RecyclerView.Adapter<HomeManager.RecyclerViewHolder> {
    private static DisplayImageOptions displayOptions;
    static View v1;
    private SparseBooleanArray mCheckedItems = new SparseBooleanArray();

    static {
        displayOptions = DisplayImageOptions.createSimple();
    }

    public static class RecyclerViewHolder extends RecyclerView.ViewHolder {

        CheckBox mCheck;

        RecyclerViewHolder(final View itemView) {
            super(itemView);

            mCheck = (CheckBox) itemView.findViewById(R.id.PROJECT_fav);
            SharedPreferences update = v1.getContext().getSharedPreferences("my_prefs", 0);
            String Check = update.getString("Check", "");
            Log.e("Checked Array = ", Check);

        }
    }

    @Override
    public RecyclerViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
        v1 = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.recyclerview_item, viewGroup, false);

        return new RecyclerViewHolder(v1);

    }

    @Override
    public void onBindViewHolder(final RecyclerViewHolder viewHolder, int i) {

//      viewHolder.mCheck.setChecked(mCheckedItems);


        viewHolder.mCheck.setChecked(mCheckedItems.get(i));
        viewHolder.mCheck.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
                if (isChecked) {
                    Snackbar snackbar = Snackbar.make(viewHolder.itemView, "Item Favorited", Snackbar.LENGTH_SHORT);
                    snackbar.show();
                } else {
                    Snackbar snackbar = Snackbar.make(viewHolder.itemView, "Item Unfavorited", Snackbar.LENGTH_SHORT);
                    snackbar.show();
                }
                int position = viewHolder.getAdapterPosition();
                mCheckedItems.put(position, isChecked);
                List<Integer> selected = new ArrayList<>();
                for (int i = 0; i < mCheckedItems.size(); i++) {
                    final boolean checked = mCheckedItems.valueAt(i);
                    if (checked) {
                        selected.add(mCheckedItems.keyAt(i));
                    }
                }
                Log.e("Checked Array = ", String.valueOf(selected));
                SharedPreferences prefs = v1.getContext().getSharedPreferences("my_prefs", Context.MODE_PRIVATE);
                SharedPreferences.Editor edit = prefs.edit();
                edit.putString("Checkbox", String.valueOf(selected));
                edit.commit();
                Log.e("Shared Preference = ", String.valueOf(edit));
            }
        });

}
4

2 回答 2

1

问题很简单——您必须使用相同的密钥进行存储和访问。

您当前正在尝试使用“检查”键访问您存储的数据：

SharedPreferences update = v1.getContext().getSharedPreferences("my_prefs", 0);
String Check = update.getString("Check", "");

但是您使用“复选框”键存储它：

SharedPreferences prefs = v1.getContext().getSharedPreferences("my_prefs", Context.MODE_PRIVATE);
SharedPreferences.Editor edit = prefs.edit();
edit.putString("Checkbox", String.valueOf(selected));
edit.commit();

两者都使用“检查”或“复选框”！你不能混搭。

于 2015-12-16T06:10:55.747 回答
1

您已将 trh 字符串放入共享首选项中 Checkbox

 edit.putString("Checkbox", String.valueOf(selected));

但是你得到的字符串叫做 Check

SharedPreferences update = v1.getContext().getSharedPreferences("my_prefs",0);
    String Check = update.getString("Check", "");

将其更改为

 String Check = update.getString("Checkbox", "");
于 2015-12-16T06:11:59.760 回答