Question

我有一个recyclerView，其中包含已安装应用程序的名称，程序包名称和图标。我已将复选框添加到recyclerView中，并且由于我在查看一个框并滚动时视图的回收性质，然后框的状态发生了变化。因此，我想知道的是，有什么方法可以保持滚动后的复选框状态吗？我尝试了this，但无法掌握。我没有DataModel班。这是我的回收站适配器：

public class AppsAdapter extends RecyclerView.Adapter<AppsAdapter.ViewHolder>{

    Context context1;
    List<String> stringList;

    public AppsAdapter(Context context, List<String> list){

        context1 = context;

        stringList = list;
    }

    public static class ViewHolder extends RecyclerView.ViewHolder{

        public CardView cardView;
        public ImageView imageView;
        public TextView textView_App_Name;
        public TextView textView_App_Package_Name;
        public CheckBox checkBox;


        public ViewHolder (View view){

            super(view);

            this.setIsRecyclable(false);

            cardView = (CardView) view.findViewById(R.id.card_view);
            imageView = (ImageView) view.findViewById(R.id.imageview);
            textView_App_Name = (TextView) view.findViewById(R.id.Apk_Name);
            textView_App_Package_Name = (TextView) view.findViewById(R.id.Apk_Package_Name);
            checkBox = (CheckBox)view.findViewById(R.id.cb);

        }
    }

    @Override
    public AppsAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType){

        View view2 = LayoutInflater.from(context1).inflate(R.layout.cardview_layout,parent,false);

        ViewHolder viewHolder = new ViewHolder(view2);

        return viewHolder;
    }

    @Override
    public void onBindViewHolder(final ViewHolder viewHolder, final int position){

        ApkInfoExtractor apkInfoExtractor = new ApkInfoExtractor(context1);

        final String ApplicationPackageName = (String) stringList.get(position);
        String ApplicationLabelName = apkInfoExtractor.GetAppName(ApplicationPackageName);
        Drawable drawable = apkInfoExtractor.getAppIconByPackageName(ApplicationPackageName);

        viewHolder.textView_App_Name.setText(ApplicationLabelName);

        viewHolder.textView_App_Package_Name.setText(ApplicationPackageName);

        viewHolder.imageView.setImageDrawable(drawable);

        viewHolder.checkBox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(CompoundButton compoundButton, boolean b) {
                //
            }
        });

    }



    @Override
    public int getItemCount(){

        return stringList.size();
    }


}

Answer 1

不要在OnBindViewHolder中设置Click和getPosition。在ViewHolder中使用它们并获取位置-getAdapterPosition（）。祝您好运。

Answer 2

您可以使用 SparseBooleanArray ，它与地图相似，但它是一个int和boolean键值对，用于存储项目列表中所有项目的状态，然后使用这些键和值在切换选中状态时进行比较。

    public static SparseBooleanArray itemCheckBoxState = new SparseBooleanArray();

并在点击处理程序中：

@Override
        public void onClick(View v) {
            int adapterPosition = getAdapterPosition();
            if (!itemCheckBoxState .get(adapterPosition, false)) {
                mCheckedTextView.setChecked(true);
                itemCheckBoxState .put(adapterPosition, true);
            }
            else  {
                mCheckedTextView.setChecked(false);
                itemCheckBoxState .put(adapterPosition, false);
            }
}

和：

    ViewHolder(View itemView) {
        super(itemView);
        mCheckedTextView = (CheckedTextView) itemView.findViewById(R.id.checked_text_view);
        itemView.setOnClickListener(this);
    }

    void bind(int position) {
        if (!itemCheckBoxState .get(position, false)) {
            mCheckedTextView.setChecked(false);}
        else {
            mCheckedTextView.setChecked(true);
        }

}

复选框状态未保存在RecyclerView中

2 个答案: