RecyclerView的使用方法

RecyclerView是Android5.x以后新有的一个控件，可以简单的将其理解为ListView和GridView的一个升级。其具体的优势我就不说了，这里有前人更好的文章http://blog.youkuaiyun.com/lmj623565791/article/details/45059587

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1 准备工作
因为RecyelerView是Android5.x新有的控件，因此想要对低版本的系统兼容的话，就必须使用support-v7包。在Android Studio里面是在build.gradle文件里面的dependencies
处添加 compile ‘com.android.support:appcompat-v7:23.0.1’，我这里是23.0.1版本的v7包。如下
所示：

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    compile 'com.android.support:design:23.0.1'
    compile 'com.android.support:appcompat-v7:23.0.1'
    compile 'com.android.support:recyclerview-v7:23.0.1'
    compile 'com.android.support:cardview-v7:23.0.1'
}

2 布局文件
布局文件很简单，注意要用v7包下的RecyclerView

 <android.support.v7.widget.RecyclerView
            android:id="@+id/recyclerView"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:scrollbars="none" />

3 RecyclerView.Adapter
RecyyclerView和ListView一样也是要通过Adapter来绑定数据，只是和ListView不同的是适配器不在是继承BaseAdapter了，而是RecyclerView.Adapter。

MRViewAdapter.java

package listviewse.lc.com.listviewse.adapter;

import android.content.Context;
import android.support.v7.widget.RecyclerView;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import java.util.List;

import listviewse.lc.com.listviewse.R;


/**
 * Created by HP on 2016/5/28.
 */
public class MRViewAdapter extends  RecyclerView.Adapter<MRViewHolder> {
    private List<String> list;
    private Context context;
    LayoutInflater mInflater;
    RecyclerItemClickListener recyclerItemClickListener;

    public MRViewAdapter(List<String> list, Context context) {
        this.list = list;
        this.context = context;
        mInflater = LayoutInflater.from(context);
    }
    public void setRecyclerItemClickListener(RecyclerItemClickListener recyclerItemClickListener)
    {
        this.recyclerItemClickListener=recyclerItemClickListener;
    }

   public interface RecyclerItemClickListener
    {
        public void OnItemClick(View v,int pos);
    }


    @Override
    public MRViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View view=mInflater.inflate(R.layout.item,parent,false);
        MRViewHolder viewHolder=new MRViewHolder(view);

        return viewHolder;
    }

    @Override
    public void onBindViewHolder(MRViewHolder holder, final int position) {
        if (holder==null)
        {
            Log.e("ADapter","holder is null");
        }
        if (list==null)
        {
            Log.e("ADapter","list is not null"+list.size());
        }
        View view=holder.itemView;
        view.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                recyclerItemClickListener.OnItemClick(view,position);
            }
        });
        holder.mTextView.setText(list.get(position));
    }

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

MRViewHolder.java

package listviewse.lc.com.listviewse.adapter;

import android.support.v7.widget.RecyclerView;
import android.view.View;
import android.widget.TextView;

import listviewse.lc.com.listviewse.R;

/**
 * Created by HP on 2016/5/28.
 */
class MRViewHolder extends RecyclerView.ViewHolder {
    TextView mTextView;

    public MRViewHolder(View itemView) {
        super(itemView);
        mTextView = (TextView) itemView.findViewById(R.id.tv_item);
    }
}

4 Activity

package listviewse.lc.com.listviewse;

import android.app.Activity;
import android.content.Context;
import android.graphics.Color;
import android.os.Bundle;
import android.support.design.widget.CollapsingToolbarLayout;
import android.support.design.widget.TabLayout;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.DefaultItemAnimator;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.StaggeredGridLayoutManager;
import android.support.v7.widget.Toolbar;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;


import java.util.ArrayList;
import java.util.List;

import listviewse.lc.com.listviewse.adapter.MRViewAdapter;

/**
 * 本例主要展示CollapsingToolbarLayout的使用
 * Created by HP on 2016/5/27.
 */
public class MenuActivity extends AppCompatActivity implements MRViewAdapter.RecyclerItemClickListener {
    ListView lv_Menu;
    List<String> list = new ArrayList<>();

    private RecyclerView mRecyclerView;
    CollapsingToolbarLayout ctl_CollapsingToolbarLayout;

    MRViewAdapter adapter;
    Toolbar mToolBar;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.menu_ac);
        initViews();
        initListener();
    }

    private void initListener() {
        adapter.setRecyclerItemClickListener(this);
    }

    private void initData() {
        for (int i = 0; i < 20; i++) {
            list.add("Something" + (i + 1));
        }
    }
    private void initViews() {
        ctl_CollapsingToolbarLayout = (CollapsingToolbarLayout) findViewById(R.id.ctl_CollapsingToolbarLayout);
        ctl_CollapsingToolbarLayout.setTitle("菜谱大全");

        ctl_CollapsingToolbarLayout.setExpandedTitleColor(Color.WHITE);
        ctl_CollapsingToolbarLayout.setCollapsedTitleTextColor(Color.GREEN);//设置缩放以后ToolBar上面的Color

        mToolBar = (Toolbar) findViewById(R.id.tb_menuac);
        setSupportActionBar(mToolBar);
        getSupportActionBar().setDisplayHomeAsUpEnabled(true);
        mToolBar.setNavigationOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                onBackPressed();
            }
        });
        //设置RecyclerView的显示样式是列表
        LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this);
        //设置RecyclerView的显示样式为网格，其中第一个参数表示每行的View的个数，第二个参数表示RecyclerView的滑动方向
//        StaggeredGridLayoutManager staggeredGridLayoutManager=new StaggeredGridLayoutManager(3,StaggeredGridLayoutManager.VERTICAL);
        mRecyclerView = (RecyclerView) this.findViewById(R.id.recyclerView);
//        mRecyclerView.setLayoutManager(new StaggeredGridLayoutManager(2, StaggeredGridLayoutManager.VERTICAL));
        mRecyclerView.setLayoutManager(linearLayoutManager);
        mRecyclerView.setItemAnimator(new DefaultItemAnimator());
        initData();
        adapter = new MRViewAdapter(list, this);
        mRecyclerView.setAdapter(adapter);
    }

    @Override
    public void OnItemClick(View v, int pos) {
        Toast.makeText(getApplicationContext(), "Click Me" + pos, Toast.LENGTH_SHORT).show();
    }
}

由于本人偷懒了将两个例子放在了一个项目里面写，所以在Activity中可以看到一些关于CollapsingToolbarLayout的内容，可以将其忽略。。。。。

5 ItemClick事件的实现
RecyclerView本身没有为我们提供ItemClick事件，因此我们只能自己去写了。主要利用的是接口回调机制，并且在Adapter中去实现上面代码中也有所体现 。

效果图：