android - 在 RecyclerView 中向左或向右滑动

Question

我尝试向左或向右滑动我的 RecyclerView List，但我不知道我做错了什么。我尝试了很多可行的解决方案，但它们都不适合我。

这是我的 fragment :

import android.app.Fragment;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.v7.widget.DividerItemDecoration;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.LinearSnapHelper;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Toast;

import java.util.ArrayList;

import de.christian_heinisch.studenttodo.adapters.ToDoListRecyclerViewAdapter;
import de.christian_heinisch.studenttodo.database.ToDo;
import de.christian_heinisch.studenttodo.database.ToDoDataSource;


/**
 * A simple {@link Fragment} subclass.
 */
public class ToDoFragment_RV extends Fragment {


    View rootview;

    private ToDoDataSource dataSource_todo;
    private RecyclerView mRecyclerView;
    private RecyclerView new_mRecyclerView;
    private RecyclerView.Adapter mAdapter;
    private RecyclerView.LayoutManager mLayoutManager;
    private RecyclerView.LayoutManager new_mLayoutManager;
    private static String LOG_TAG = "RecyclerViewActivity";


    public ToDoFragment_RV() {
        // Required empty public constructor
    }




    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        rootview = inflater.inflate(R.layout.fragment_to_do_rv, container, false);

        mRecyclerView = (RecyclerView) rootview.findViewById(R.id.rv);
        mRecyclerView.setHasFixedSize(true);
        LinearSnapHelper snapHelper = new LinearSnapHelper();
        snapHelper.attachToRecyclerView(mRecyclerView);
        mLayoutManager = new LinearLayoutManager(getContext());
        mRecyclerView.setLayoutManager(mLayoutManager);
        mAdapter = new ToDoListRecyclerViewAdapter(getContext(), getDataSet());
        mRecyclerView.setAdapter(mAdapter);
        mRecyclerView.setOnFlingListener(snapHelper);

        RecyclerView.ItemDecoration itemDecoration =
                new DividerItemDecoration(getContext(), LinearLayoutManager.VERTICAL);
        mRecyclerView.addItemDecoration(itemDecoration);


        new_mRecyclerView = (RecyclerView) rootview.findViewById(R.id.rv_checked);
        new_mRecyclerView.setHasFixedSize(true);
        new_mLayoutManager = new LinearLayoutManager(getContext());
        new_mRecyclerView.setLayoutManager(new_mLayoutManager);
        mAdapter = new ToDoListRecyclerViewAdapter(getContext(), getDataSet_checked());
        new_mRecyclerView.setAdapter(mAdapter);
        RecyclerView.ItemDecoration newitemDecoration =
                new DividerItemDecoration(getContext(), LinearLayoutManager.VERTICAL);
        new_mRecyclerView.addItemDecoration(newitemDecoration);

  //      setHasOptionsMenu(true);

        FloatingActionButton fab = (FloatingActionButton) rootview.findViewById(R.id.fbToDoAdd);
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                ((StartActivity)getContext()).DialogAddToDO();
            }
        });


        return rootview;
    }

    private ArrayList<ToDo> getDataSet() {
        dataSource_todo = new ToDoDataSource(getContext());
        dataSource_todo.open();

        ArrayList<ToDo> arrayOfToDo = null;
        arrayOfToDo = dataSource_todo.getToDoForList("false");
        dataSource_todo.close();

        return arrayOfToDo;
    }

    private ArrayList<ToDo> getDataSet_checked() {
        dataSource_todo = new ToDoDataSource(getContext());
        dataSource_todo.open();

        ArrayList<ToDo> arrayOfToDo = null;
        arrayOfToDo = dataSource_todo.getToDoForList("true");
        dataSource_todo.close();

        return arrayOfToDo;
    }


}

这是我的RecyclerView 适配器

import android.app.Activity;
import android.app.Fragment;
import android.app.FragmentManager;
import android.app.FragmentTransaction;
import android.content.Context;
import android.support.v7.widget.RecyclerView;
import android.text.format.DateFormat;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.widget.CheckBox;
import android.widget.TextView;

import java.util.ArrayList;
import java.util.Calendar;
import java.util.Locale;

import de.christian_heinisch.studenttodo.R;
import de.christian_heinisch.studenttodo.StartActivity;
import de.christian_heinisch.studenttodo.ToDoFragment_RV;
import de.christian_heinisch.studenttodo.database.ToDo;
import de.christian_heinisch.studenttodo.database.ToDoDataSource;

/**
 * Created by chris on 16.06.2017.
 */

public class ToDoListRecyclerViewAdapter extends RecyclerView
        .Adapter<ToDoListRecyclerViewAdapter
        .DataObjectHolder> {

    private ArrayList<ToDo> mDataset;
    private static MyClickListener myClickListener;
    private Context mContext;

    ToDoDataSource dataSource = new ToDoDataSource(mContext);

    public static class DataObjectHolder extends RecyclerView.ViewHolder
            implements View
            .OnClickListener {
        TextView label;
        TextView dateTime;
        CheckBox checked;


        public DataObjectHolder(View itemView) {
            super(itemView);

            label = (TextView) itemView.findViewById(R.id.textView_item_todolist_content);
            dateTime = (TextView) itemView.findViewById(R.id.textView_item_todolist_Date);
            checked = (CheckBox) itemView.findViewById(R.id.cbToDo);
            //itemView.setOnClickListener(this);

        }

        @Override
        public void onClick(View v) {
            myClickListener.onItemClick(getPosition(), v);
        }
    }

    public void setOnItemClickListener(MyClickListener myClickListener) {
        this.myClickListener = myClickListener;

    }

    public ToDoListRecyclerViewAdapter(Context context, ArrayList<ToDo> myDataset) {
        mDataset = myDataset;
        mContext = context;
    }

    @Override
    public DataObjectHolder onCreateViewHolder(ViewGroup parent,
                                               int viewType) {
        View view = LayoutInflater.from(parent.getContext())
                .inflate(R.layout.item_todolist, parent, false);

        DataObjectHolder dataObjectHolder = new DataObjectHolder(view);

        return dataObjectHolder;
    }



    @Override
    public void onBindViewHolder(final DataObjectHolder holder, final int position) {
        holder.label.setText(mDataset.get(position).getToDo());
        holder.dateTime.setText(getDate(mDataset.get(position).isDate()));
        if(mDataset.get(position).isChecked().equalsIgnoreCase("true")){
            holder.checked.toggle();
        }

        holder.itemView.setOnTouchListener(new View.OnTouchListener() {

            float _xSwipe1;
            float _xSwipe2;

            @Override
            public boolean onTouch(View v, MotionEvent event)
            {
                switch (event.getAction())
                {
                    case MotionEvent.ACTION_DOWN:
                        _xSwipe1 = event.getX();
                        break;

                    case MotionEvent.ACTION_UP:
                        _xSwipe2 = event.getX();

                        float deltaX = _xSwipe2 - _xSwipe1;

                        if (deltaX < 0)
                        {
                            Log.e("SWIPE", "Right to Left swipe");
                        }

                        else if (deltaX >0)
                        {
                            Log.e("SWIPE", "Left to right swipe");
                        }

                        break;
                }

                return false;
            }
        });


        // Set onClicklistener
        holder.label.setOnLongClickListener(new View.OnLongClickListener() {
            public boolean onLongClick(View view) {
                System.out.println("Position " + position);
                edit(mDataset.get(position).getId());
                //notifyDataSetChanged();
                return false;
            }

        });

        holder.dateTime.setOnLongClickListener(new View.OnLongClickListener() {
            public boolean onLongClick(View view) {
                edit(mDataset.get(position).getId());
                return false;
            }

        });

        holder.checked.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {

                dataSource = new ToDoDataSource(mContext);
                dataSource.open();
                // TODO Auto-generated method stub
                if(holder.checked.isChecked()){
                    System.out.println("Checked");
                    dataSource.updateToDo(mDataset.get(position).getId(), mDataset.get(position).getToDo(), "true", mDataset.get(position).isDate());
                }else{
                    System.out.println("un-Checked");
                    dataSource.updateToDo(mDataset.get(position).getId(), mDataset.get(position).getToDo(), "false", mDataset.get(position).isDate());
                }
                dataSource.close();
            }
        });
    }



    public void addItem(ToDo dataObj, int index) {
        mDataset.add(dataObj);
        notifyItemInserted(index);
    }

    public void deleteItem(int index) {
        mDataset.remove(index);
        notifyItemRemoved(index);
    }

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

    public interface MyClickListener {
        public void onItemClick(int position, View v);
    }


    private String getDate(long time) {
        Calendar cal = Calendar.getInstance(Locale.GERMAN);
        cal.setTimeInMillis(time);
        String date = DateFormat.format("dd.MM.yyyy", cal).toString();
        return date;
    }

    private void edit(long l){

        ((StartActivity)mContext).DialogEditToDO(l);

    }


}

Answer 1

在 MotionEvent.ACTION_DOWN 情况下返回 true 可能会解决您的问题。