Android学习-第17天

今天的任务为实现ViewHolder和Adapter，代码如下：

List_item_crime.xml:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical"
    android:padding="8dp">

    <TextView
        android:id="@+id/crime_title"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Crime Title"/>

    <TextView
        android:id="@+id/crime_date"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Crime Date"/>

</LinearLayout>

CrimeListFragment.java:

package com.bignerdranch.android.criminallntent;

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 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 void updateUI() {
        CrimeLab crimeLab=CrimeLab.get(getActivity());
        List<Crime> crimes=crimeLab.getCrimes();

        mAdapter=new CrimeAdapter(crimes);
        mCrimeRecyclerView.setAdapter(mAdapter);
    }

    private class CrimeHolder extends RecyclerView.ViewHolder{

        public CrimeHolder(LayoutInflater inflater,ViewGroup parent) {
            super(inflater.inflate(R.layout.list_item_crime,parent,false));
        }
    }

    private class CrimeAdapter extends RecyclerView.Adapter<CrimeHolder>{
        private List<Crime> mCrimes;
        public CrimeAdapter(List<Crime> crimes){
            mCrimes=crimes;
        }

        @Override
        public CrimeHolder onCreateViewHolder(ViewGroup parent, int viewType) {
            LayoutInflater layoutInflater=LayoutInflater.from(getActivity());

            return new CrimeHolder(layoutInflater,parent);
        }

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

        }

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

截图如下：