从子 RecyclerView 更新父 RecyclerView 中的值

Question

I have two RecyclerViews. RecyclerView A and RecyclerView B. Every item of RecyclerView A contains RecyclerView B and a TextView. That is RecyclerView B is child of RecyclerView A.

How can i update the value of TextView in RecyclerView A on Button press which is in every item of RecyclerView B. TextView Belongs to Item of RecyclerView A.

Answer 1

You must be inflating the RecuclerView B inside onBindViewHolder of RecyclerView A, there only you can pass the position of that particular RecyclerViewA's child in RecyclerViewB's adapter. I'm assuming that you can have access to LayoutManager and RecyclerView instance of RecyclerView A.

RecyclerViewA's onBindViewHolder:

@Override
public void onBindViewHolder(final ViewHolder holder, int positionInRecyclerViewA) {
    RecyclerViewAdapterB adapterB = new RecyclerViewAdapterB(positionInRecyclerViewA);
    holder.recyclerViewB.setAdapter(adapterB);
}

RecyclerViewB's onBindViewHolder:

@Override
public void onBindViewHolder(final ViewHolder holder, int position) {
    holder.button.setOnClickListener(new OnClickListener(){
        public void onClick(View view) {
            onButtonClick();
        }
    }
}
private void onButtonClick() {
    if (positionInRecyclerViewA >= linearLayoutManagerA.findFirstVisibleItemPosition() &&
            positionInRecyclerViewA <= linearLayoutManagerA.findLastVisibleItemPosition()) {
        Adapter.ViewHolder holder = (Adapter.ViewHolder) recyclerViewA
                .findViewHolderForAdapterPosition(positionInRecyclerViewA);
        holder.textView.setText("text");
    }
}

Update you list as well so next time when you scroll it'll have latest data.

Answer 2

Use this.. in recyclerView2 adapter.. and declare.. public static RecyclerViewAdapterOne reyclerViewAdapOne = ... ; in the activity and onClick() of button in recylerView 2 adapter use Activity.reyclerViewAdapOne.updateValue(newText); and in RecyclerViewAdapterOne add this function ..

updateValue(String newText) //updating the recycler adapter of recyclerview one

  { 
    this.list.set( your_index, newText); // i assume this is a generic string list
    this.notifyDataSetChanged();

    }

Answer 3

Receive the button click within your activity/fragment or what ever on click listener you like. Change the resources which are holding the text (normally within your data set which you set to the adapter each item should know which text to show). Call notifyDataSetChanged() on RecyclerView A.

Answer 4

使用 EventBus，发布事件并在主活动上订阅它并通知适配器

Answer 5

put both adapters in one class.send parent position and RecyclerViewB lists from RecyclerViewA Adapter to RecyclerViewB Adapter.then notify RecyclerViewA from RecyclerViewB Adapter.

parent model:

 public class ExampleModel {

        public int text = 0;

        public List<Button> child_lst;
    }

in your Activity:

public class TestActivity extends AppCompatActivity {

    RecyclerView recyclerView_A;
    List<ExampleModel> parent_lst;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_test);

        recyclerView_A.setLayoutManager(new LinearLayoutManager(this));
        recyclerView_A.setAdapter(new AAdapter());

    }


    public class AAdapter extends RecyclerView.Adapter <AAdapter.Aviewholder> {

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

            ExampleModel em = parent_lst.get(position);

            holder.textView.setText(em.text+"");

            holder.recyclerView_b.setLayoutManager(new LinearLayoutManager(getApplicationContext()));
            holder.recyclerView_b.setAdapter(new BAdapter(em.child_lst,position));

        }

        @Override
        public int getItemCount()
        {
            return parent_lst.size();
        }
    }

    public class BAdapter extends RecyclerView.Adapter <BAdapter.Bviewholder> {

        List<Button> child_lst;
        int parent_position;


        public BAdapter(List<Button> child_lst,int parent_position){

            this.child_lst = child_lst;
            this.parent_position = parent_position;

        }


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

            holder.btn.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    parent_lst.get(parent_position).text += 1;
                    recyclerView_A.getAdapter().notifyItemChanged(parent_position);
                }
            });

        }

        @Override
        public int getItemCount()
        {
            return child_lst.size();
        }

    }

}