java - Android RecyclerView 仅显示 100 项中的一项

Question

我是 Android 编程新手，我对 recyclerview 有疑问(我正在阅读一本 Android 编程书籍和练习):尽管我传递了 100 个项目的列表，但它只显示一个项目

这是该类的代码:

package com.training.criminalintent;

import android.content.Intent;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.CheckBox;
import android.widget.TextView;
import android.widget.Toast;

import java.util.List;


public class CrimeListFragment extends Fragment {

    private RecyclerView mCrimeRecyclerView;
    private CrimeAdapter mAdapter;

    @Override
    public View onCreateView(LayoutInflater inflater,ViewGroup container,
                        Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_crime_list, container, false);
        mCrimeRecyclerView = (RecyclerView) view
                .findViewById(R.id.crime_recycler_view);
        mCrimeRecyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));

        updateUI();

        return view;
    }

    private class CrimeHolder extends RecyclerView.ViewHolder implements View.OnClickListener{

        private Crime mCrime;

        private TextView mTitleTextView;
        private TextView mDateTextView;
        private CheckBox mSolvedCheckBox;

        public CrimeHolder(View itemView) {
            super(itemView);
            itemView.setOnClickListener(this);
            mTitleTextView = (TextView)
                    itemView.findViewById(R.id.list_item_crime_title_text_view);
            mDateTextView = (TextView)
                    itemView.findViewById(R.id.list_item_crime_date_text_view);
            mSolvedCheckBox = (CheckBox)
                    itemView.findViewById(R.id.list_item_crime_solved_check_box);
        }

        public void bindCrime(Crime crime) {
            mCrime = crime;
            mTitleTextView.setText(mCrime.getTitle());
            mDateTextView.setText(mCrime.getDate().toString());
            mSolvedCheckBox.setChecked(mCrime.isSolved());
        }

        @Override
        public void onClick(View v) {
            Intent intent = new Intent(getActivity(), CrimeActivity.class);
            startActivity(intent);
        }
    }

    private class CrimeAdapter extends RecyclerView.Adapter<CrimeHolder> {
        private List<Crime> mCrimes;
        public CrimeAdapter(List<Crime> crimes) {
            mCrimes = crimes;
        }
        @Override
        public int getItemCount() {
            return mCrimes.size();
        }
        @Override
        public CrimeHolder onCreateViewHolder(ViewGroup parent, int viewType) {
            LayoutInflater layoutInflater = LayoutInflater.from(getActivity());
            View view = layoutInflater
                    .inflate(R.layout.list_item_crime, parent, false);
            return new CrimeHolder(view);
        }
        @Override
        public void onBindViewHolder(CrimeHolder holder, int position) {
            Crime crime = mCrimes.get(position);
            holder.bindCrime(crime);
        }
    }

    private void updateUI() {
        CrimeLab crimeLab = CrimeLab.get(getActivity());
        List<Crime> crimes = crimeLab.getCrimes();
        mAdapter = new CrimeAdapter(crimes);
        mCrimeRecyclerView.setAdapter(mAdapter);
    }
}

预先感谢您的帮助，

Answer 1

这本书不知何故犯了一个错误。

实际输入应为android:layout_height="wrap_content"