如何在片段和适配器之间创建接口

Question

我已经能够在适配器中创建一个接口来与片段通信。

这是适配器代码

public class AgroInfoAdapter extends RecyclerView.Adapter<AgroInfoAdapter.ViewHolder> {
    private Context mContext;
    ArrayList<JsonObject> extensionItem = new ArrayList<>();
    public Typeface tf;


    public AgroInfoAdapter.AgroInfoAdapterListener listener;

    public AgroInfoAdapter(Context context, ArrayList<JsonObject> extensionItem) {
        this.extensionItem = extensionItem;
        this.mContext = context;
        this.tf = Typeface.createFromAsset(context.getAssets(), "FiraSans-Light.ttf");
    }

    @Override
    public AgroInfoAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View itemLayoutView = LayoutInflater.from(parent.getContext())
                .inflate(R.layout.list_crop_info, null);
        AgroInfoAdapter.ViewHolder viewHolder = new AgroInfoAdapter.ViewHolder(itemLayoutView);
        return viewHolder;

    }

    public static class ViewHolder extends RecyclerView.ViewHolder {
        @BindView(R.id.header)
        public TextView header;
        @BindView(R.id.body)
        public TextView body;
        @BindView(R.id.thumbnail)
        public ImageView thumbnail;

        @BindView(R.id.button)
        public Button button;


        @BindView(R.id.downloadProgressView)
        DownloadProgressView downloadProgressView;

        @BindView(R.id.row)
        public LinearLayout row;

        public ViewHolder(View itemLayoutView) {
            super(itemLayoutView);
            ButterKnife.bind(this, itemLayoutView);
        }
    }

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


        try {
            JsonObject sl = extensionItem.get(position);
            viewHolder.header.setText(sl.get("title").getAsString());
            if ((sl.get("title").getAsString()).equals("Land preparation")) {

                viewHolder.button.setVisibility(View.VISIBLE);
            }
            Glide.with(mContext).load(CONFIG.IMAGE_URL+ sl.get("photo_url").getAsString())
                    .thumbnail(0.5f)
                    .apply(new RequestOptions()
                            .diskCacheStrategy(DiskCacheStrategy.ALL)
                            .fallback(R.drawable.fallback)
                            .placeholder(R.drawable.progress_animation)
                            .error(R.drawable.fallback)
                    )
                    .into(viewHolder.thumbnail);
            String description="";
            for (JsonElement e:sl.get("description").getAsJsonArray()){
                if(!e.getAsString().trim().isEmpty() && CharMatcher.javaUpperCase().or(CharMatcher.javaLetter().negate()).matchesAllOf(e.getAsString().trim())) {
                    SpannableString s1 = new SpannableString(e.getAsString());
                    s1.setSpan(new BulletSpan(20), 1, e.getAsString().length(), 0);
                    description +=s1 + "\n\n";

                }else if(!e.getAsString().trim().isEmpty()) {
                    SpannableString s1 = new SpannableString(e.getAsString());
                    s1.setSpan(new BulletSpan(20), 1, e.getAsString().length(), 0);
                    description +=s1 + "\n\n";;
                    viewHolder.body.setText(description);
                    viewHolder.body.setTypeface(tf);

                }

            }




        } catch (Exception e) {
        }

        applyClickEvents(viewHolder, position);

    }

    public interface AgroInfoAdapterListener {

        void onCartRowClicked(View view, DownloadProgressView downloadProgressView, int position);

    }

    private void applyClickEvents(final AgroInfoAdapter.ViewHolder holder, final int position) {
        holder.button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                listener.onCartRowClicked(view, holder.downloadProgressView, position);
            }
        });
    }




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

}

这是我连接到适配器的代码

    AgroInfoAdapter adapter;

    @BindView(R.id.rv)
    RelativeLayout _RecyclerViewLayout;
    @BindView(R.id.empty_rv)
    RelativeLayout _EmptyRecyclerViewLayout;
    @BindView(R.id.recycler_desc)
    RecyclerView recyclerView;

    Toolbar mToolbar;
    @BindView(R.id.progress_bar)
    ProgressBar progressBar;

    @BindView(R.id.rv_layout) RelativeLayout relativeLayout;

    ArrayList<JsonObject> ins = new ArrayList<>();

    AgroInfoActivity.OnCropperSpinnerSelectedListener listener;

    @Override
    public void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        listener = new AgroInfoActivity.OnCropperSpinnerSelectedListener() {
            @Override
            public void onItemSelected(String pos) {
                new LongOperation().execute(pos);
            }
        };

        ((AgroInfoActivity)getActivity()).addCropperSpinnerSelectedListener(listener);
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_ext_land, container, false);
        ButterKnife.bind(this,view);
        RecyclerView.LayoutManager mLayoutManager = new GridLayoutManager(getActivity(), 1);
        recyclerView.setLayoutManager(mLayoutManager);
        recyclerView.addItemDecoration(new GridSpacingItemDecoration(1, dpToPx(10), true));
        recyclerView.setItemAnimator(new DefaultItemAnimator());
        adapter = new AgroInfoAdapter(getActivity(), ins);
        recyclerView.setAdapter(adapter);
        return view;
    }

    @Override
    public void onResume() {

        new LongOperation().execute(((AgroInfoActivity)getActivity()).cropsSpinner.getSelectedItem().toString());
        super.onResume();
    }
    private class LongOperation extends AsyncTask<String, Void, ArrayList<JsonObject>> {

        @Override
        protected ArrayList<JsonObject> doInBackground(String... params) {
            try {
                couchdbCropInfo = new CouchdbCropInfo(getActivity());
                return couchdbCropInfo.allCropInfo(params[0],TYPE);
            } catch (CouchbaseLiteException e) {
                e.printStackTrace();
            }
            return null;
        }

        @Override
        protected void onPostExecute(ArrayList<JsonObject> result) {
            ins.addAll(result);
            adapter.notifyDataSetChanged();
            if (ins.isEmpty()) {
                _RecyclerViewLayout.setVisibility(View.GONE);
                _EmptyRecyclerViewLayout.setVisibility(View.VISIBLE);
            } else {
                _RecyclerViewLayout.setVisibility(View.VISIBLE);
                _EmptyRecyclerViewLayout.setVisibility(View.GONE);
            }
            relativeLayout.setVisibility(View.VISIBLE);
            progressBar.setVisibility(View.GONE);
        }

        @Override
        protected void onPreExecute() {
            relativeLayout.setVisibility(View.GONE);
            progressBar.setVisibility(View.VISIBLE);
            ins.clear();
        }

        @Override
        protected void onProgressUpdate(Void... values) {}
    }



    @Override
    public void onCartRowClicked(View view, DownloadProgressView downloadProgressView, int position) {

        Bundle bundle = new Bundle();
            FragmentTransaction fragmentTransaction = getActivity()
                    .getFragmentManager()
                    .beginTransaction();
            Fragment fragmentB = new PostFragment();
            fragmentB.setArguments(bundle);
            fragmentTransaction.replace(R.id.parent, fragmentB);
            fragmentTransaction.addToBackStack(null);
            fragmentTransaction.commit();

    }
}

基本上我想要实现的是当我点击按钮时我想调用一个片段。 activity 是一个包含大约 5 个片段的表格。当我点击按钮时。是什么导致了这种情况，我怎样才能最好地解决它或如何做到这一点？提前致谢。

Answer 1

在您声明适配器的地方或在适配器的构造函数中，启动侦听器。

在片段端，

class Test extends Fragment {
AdapterClass adapter = new AdapterClass();
adapter.setListner(..)
view.setAdapter(adapter);


@Override
public void onCartRowClicked(View view, DownloadProgressView downloadProgressView, int position) {

}
}

在适配器中 class

class AdapterClass {

private AgroInfoAdapterListener listner;

public setListner(AgroInfoAdapterListener listner) {
this.listner = listner;
}


public interface AgroInfoAdapterListener {

    void onCartRowClicked(View view, DownloadProgressView downloadProgressView, int position);

}

private void applyClickEvents(final AgroInfoAdapter.ViewHolder holder, final int position) {
    holder.button.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {

        }
    });
}

}

如何在片段和适配器之间创建接口

How to create an interface between a fragment and an adapter

android

android-adapter

android-fragments