Question

我有recyclerview，其中显示的项目名称分别为+/-，由+/-按钮增加和减少的项目名称，项目速率和数量。现在，我想从recyclerview的每个项目中获取所有值，并将其通过服务器发送或将其保存到本地数据库，以便实现该目标。

//这是我的适配器类

公共类TeaListAdapter扩展了RecyclerView.Adapter {

    //private int num=0;
    private List<TeaListPOJO> teaItemList;
    private Context mContext;
    private Cursor cursor;
    int comboCount;

    HashMap<Object,Integer> selectedMap = new HashMap ();

    private String ItemName;
    private String itemrate;
    private String qty;

    public class MyViewHolder extends RecyclerView.ViewHolder {
        public TextView tvitemName, tvitemRate,tvcount; //number
        public ImageView ivItemImg,ivPlus,ivMinus;
        public Button btnIncrease,btnDecrease;
        RecyclerView.ViewHolder holder;


        public MyViewHolder(View view) {
            super(view);
            tvitemName = (TextView) view.findViewById(R.id.txt_item_name);
            tvitemRate = (TextView) view.findViewById(R.id.txt_item_price);
            ivItemImg= (ImageView) view.findViewById (R.id.iv_item);
            ivPlus=(ImageView) view.findViewById (R.id.row_view_final_order_iv_plus);
            ivMinus=(ImageView) view.findViewById (R.id.row_view_final_order_iv_minus);
            tvcount=(TextView) view.findViewById (R.id.row_view_final_order_tv_count);
        }
    }


    public TeaListAdapter(List<TeaListPOJO> teaItemList) {
        this.mContext=mContext;
        this.cursor=cursor;
        this.teaItemList = teaItemList;
    }

    @Override
    public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View itemView = LayoutInflater.from(parent.getContext())
                .inflate(R.layout.rv_placeorder_items, parent, false);

        return new MyViewHolder (itemView);
    }

    @Override
    public void onBindViewHolder(final MyViewHolder holder, final int position) {

        TeaListPOJO tealist = teaItemList.get(position);
        holder.tvitemName.setText(tealist.getItemName ());
        holder.tvitemRate.setText(AppConstants.INDIAN_RUPEE_SIGN.concat (tealist.getItemRate ()));

        holder.ivPlus.setOnClickListener (new View.OnClickListener () {
            @Override
            public void onClick(View view) {
                int count=0;
                try{
                    count = Integer.parseInt(holder.tvcount.getText().toString());
                }
                catch(Exception e) {
                    count = 0;
                }
                //count++;
                count = Integer.parseInt(holder.tvcount.getText().toString());
                holder.tvcount.setText(String.valueOf(count+ 1));
            }

        });

        holder.ivMinus.setOnClickListener (new View.OnClickListener () {
            @Override
            public void onClick(View view) {
                int count=0;
                try{

                    count = Integer.parseInt(holder.tvcount.getText().toString());
                }
                catch(Exception e) {
                    count = 0;
                }
                if(count>0) {
                    //count--;
                    count = Integer.parseInt (holder.tvcount.getText ().toString ());
                    holder.tvcount.setText (String.valueOf (count - 1));
                }
            }

        });

        holder.itemView.setOnClickListener (new View.OnClickListener () {
            @Override
            public void onClick(View view) {

            }
        });

       /* Intent intent = new Intent (mContext, PlaceOrderActivity.class);
        //            intent.putExtra("quantity",Integer.parseInt(quantity.getText().toString()));
        intent.putExtra ("quantity", qty);
        intent.putExtra ("item", ItemName);
        intent.putExtra ("itemrate", itemrate);

         ItemName = holder.tvitemName.getText().toString();
         qty = holder.tvcount.getText().toString();
         itemrate=holder.tvitemRate.getText ().toString ();

        Log.e("rate",itemrate);
        Log.e("qty",qty);*/


        byte[] decodedString = new byte[0];
        try {

            decodedString = Base64.decode(tealist.getImageStr(), Base64.DEFAULT);
            // tenantModelPOJO.setLogo(decodedString);
            Bitmap bmp = BitmapFactory.decodeByteArray(decodedString, 0, decodedString.length);
            holder.ivItemImg.setImageBitmap(Bitmap.createScaledBitmap(bmp, 50, 50,false));
        } catch (Exception e) {
            e.printStackTrace();
        }

    }


    @Override
    public int getItemCount() {

        return teaItemList.size();
    }

}

//这是我的活动班

公共类PlaceOrderActivity扩展了AppCompatActivity，实现了AppConstants，View.OnClickListener，WLAPIcalls.OnAPICallCompleteListener {

private List<TeaListPOJO> teaList = new ArrayList<> ();
private RecyclerView recyclerView;
private TeaListAdapter mAdapter;
private View view;
private Button btnPlaceorder;
EditText edtmsg;

public String str;

private Context mContext = PlaceOrderActivity.this;
private int itemCount;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate (savedInstanceState);
    setContentView (R.layout.activity_place_order);
    str=getIntent ().getStringExtra ("quantity");
    edtmsg= (EditText) view.findViewById (R.id.et_message);
    edtmsg.setText (str);

    setRecyclerView (view);
    getallTeaItems ();
}

List<TeaListPOJO> getTeaItemList(String str) {
    Gson gson = new Gson ();
    Type listType = new TypeToken<List<TeaListPOJO>> () {
    }.getType ();
    List<TeaListPOJO> myModelList = gson.fromJson (str, listType);
    return myModelList;
}

private List<TeaListPOJO> getallTeaItems() {
    if (new AppCommonMethods (mContext).isNetworkAvailable ()) {
        WLAPIcalls mAPIcall = new WLAPIcalls (mContext, getString (R.string.getTeaItem), this);
        mAPIcall.GetTeaItemList ();
    } else {
        Toast.makeText (mContext, R.string.no_internet, Toast.LENGTH_SHORT).show ();
    }
    return null;
}


void setRecyclerView(View view) {
    recyclerView = (RecyclerView) findViewById (R.id.recycler_view);
    mAdapter = new TeaListAdapter (teaList);
    RecyclerView.LayoutManager mLayoutManager = new LinearLayoutManager (getApplicationContext ());
    recyclerView.setLayoutManager (mLayoutManager);
    recyclerView.setItemAnimator (new DefaultItemAnimator ());
    recyclerView.setAdapter (mAdapter);
}

@Override
public void onClick(View view) {

}

@Override
public void onAPICallCompleteListner(Object item, String flag, String result) throws JSONException {
    if (getString (R.string.getTeaItem).equals (flag)) {
        Log.e ("Result", result);
        teaList = getTeaItemList (result);
        setRecyclerView (view);

    }

}

}

Answer 1

TeaListPOJO还需要一个字段来存储count。当用户单击+或-按钮并在文本视图中显示count值时，递增或递减count值，而不是直接显示。

class TeaListPojo{
    private int count;
    .....

    public int getCount()
        return this.count
    }

    public void setCount(int count)
    {
        this.count = count;
    }
}

这是用于更新计数textview的代码

public void onBindViewHolder(final MyViewHolder holder, final int position) {

    TeaListPOJO tealist = teaItemList.get(position);

    .....
    .....

    holder.ivPlus.setOnClickListener (new View.OnClickListener () {
        @Override
        public void onClick(View view) {
            tealist.setCount( tealist.getCount() + 1);
            holder.tvcount.setText(String.valueOf(count));
        }

    });

    holder.ivMinus.setOnClickListener (new View.OnClickListener () {
        @Override
        public void onClick(View view) {
                tealist.setCount(tealist.getCount() - 1)
                holder.tvcount.setText (String.valueOf (count));
            }
        }

    });
}

Answer 2

在TeaListPOJO模型中添加一个额外的属性，比如说count，当您按+/-按钮时，您必须在模型中设置计数，就像在文本视图中设置计数一样。因此，在适配器中，您具有TeaListPOJO列表。显示何时要将数据发送到服务器TeaListPOJO的获取列表，并且还有计数列表。

Answer 3

在适配器中，设置对API的调用以更改DB中的值。您不需要传递全部数据，通常您可以通过在URL中传递ID来更新正在查看的一个对象。例如 https://hostname.domain/api/object/ID 使用PUT请求并传递该行中对象的信息。

如果您也要创建后端，那么我强烈建议您进行设置，因为传递所有行的整个数据集并不是一个理想的解决方案。

如果这些都不是首先存在的，而是全部通过在应用程序中创建而创建的，则在您的主要活动上有一个按钮来保存列表，然后将整个列表传递给API调用，很可能需要将数据解析为JSON。我假设在这种情况下，如果您是在一个类中创建了这些对象的话。

Answer 4

在模型类TeaListPOJO中的

，当您增加或减少值时，请始终调用正确的项目设置方法并在模型类中设置值，并且要在服务器上发送该值，然后从modelClass列表中查找值并发送到服务器。

如何从recyclerview获取每个项目行的textview值

4 个答案: