RecyclerView介绍（二）实现ListView的效果

1.在as当中导入RecyclerView的jar包：
compile ‘com.android.support:recyclerview-v7:23.1.0’
2.在布局文件当中生命RecyclerView的控件

package demo.yangzc.com.recycledemo;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.Toolbar;
import java.util.ArrayList;
import java.util.List;
public class RecycleDemoActivity extends AppCompatActivity {
    private RecyclerView mRecyclerView;
    private List<String> mDatas;
    private RecyclerViewAdapter mAdapter;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_recycle_demo);
        initViews();
        initDatas();
    }
    private void initViews() {
        mRecyclerView = (RecyclerView) findViewById(R.id.recyclerview);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
    }
    private void initDatas() {
        mDatas = new ArrayList<String>();
        for (int i = 'A'; i <= 'z'; i++) {
            mDatas.add("" + (char) i);
        }
        mAdapter = new RecyclerViewAdapter(this, mDatas);
        mRecyclerView.setAdapter(mAdapter);
        //设置RecyclerView的布局管理
        // 1.上下文 2.放向 3.是否反向布局
        LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this, LinearLayoutManager.VERTICAL, false);
        mRecyclerView.setLayoutManager(linearLayoutManager);
        //设置RecycView的Item间的分割线
        mRecyclerView.addItemDecoration(new DividerItemDecoration(this, DividerItemDecoration.VERTICAL_LIST));
    }
}

Adapter

package demo.yangzc.com.recycledemo;
import android.content.Context;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
import java.util.List;
/**
 * @author yangzc
 * @data 2015/12/1 17:40
 * @desc RecyclerViewAdapter
 */
public class RecyclerViewAdapter extends RecyclerView.Adapter<MyViewHoder> {
    //用于每个item的布局
    private LayoutInflater mInflater;
    private Context mContext;
    protected List<String> mDatas;
    @Override
    //创建ViewHoler
    public MyViewHoder onCreateViewHolder(ViewGroup parent, int viewType) {
        //item布局
        View view = mInflater.inflate(R.layout.item_simple_textview, parent, false);
        //传入item布局
        MyViewHoder viewHoder = new MyViewHoder(view);
        return viewHoder;
    }
    public void addData(int position) {
        mDatas.add(position, "Insert One");
        //不会去刷新所有的View 就不会重置position
        notifyItemInserted(position);
    }
    public void delData(int position) {
        mDatas.remove(position);
        notifyItemRemoved(position);
    }
    @Override
    //绑定ViewHolder
    public void onBindViewHolder(final MyViewHoder holder,  int position) {
        holder.textView.setText(mDatas.get(position));
    }
    @Override
    public int getItemCount() {
        return mDatas == null ? 0 : mDatas.size();
    }
    public RecyclerViewAdapter(Context context, List<String> datas) {
        this.mContext = context;
        this.mDatas = datas;
        mInflater = LayoutInflater.from(context);
    }
}
class MyViewHoder extends RecyclerView.ViewHolder {
    TextView textView;
    public MyViewHoder(View itemView) {
        super(itemView);
        textView = (TextView) itemView.findViewById(R.id.id_tv);
    }
}

item的布局

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_margin="3dp"
    android:background="@drawable/item_bg"
    android:layout_height="72dp">

    <TextView
        android:id="@+id/id_tv"
        android:layout_width="72dp"
        android:layout_height="match_parent"
        android:gravity="center"/>


</FrameLayout>

实现间隔效果：

package demo.yangzc.com.recycledemo;
import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Rect;
import android.graphics.drawable.Drawable;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.View;
/**
 * @author yangzc
 * @data 2015/12/1 19:51
 * @desc 实现了RecyclerView添加分割线（当使用LayoutManager为LinearLayoutManager时）
 * 该实现类可以看到通过读取系统主题中的 android.R.attr.listDivider作为Item间的分割线，并且支持横向和纵向。
 */
/*
 * Copyright (C) 2014 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * limitations under the License.
 */
/**
 * This class is from the v7 samples of the Android SDK. It's not by me!
 * <p/>
 * See the license above for details.
 */
public class DividerItemDecoration extends RecyclerView.ItemDecoration {
    //获取属性的分割
    private static final int[] ATTRS = new int[]{
            android.R.attr.listDivider
    };
    public static final int HORIZONTAL_LIST = LinearLayoutManager.HORIZONTAL;
    public static final int VERTICAL_LIST = LinearLayoutManager.VERTICAL;
    private Drawable mDivider;
    private int mOrientation;
    public DividerItemDecoration(Context context, int orientation) {
        final TypedArray a = context.obtainStyledAttributes(ATTRS);
        mDivider = a.getDrawable(0);
        a.recycle();
        setOrientation(orientation);
    }
    public void setOrientation(int orientation) {
        if (orientation != HORIZONTAL_LIST && orientation != VERTICAL_LIST) {
            throw new IllegalArgumentException("invalid orientation");
        }
        mOrientation = orientation;
    }
    @Override
    public void onDraw(Canvas c, RecyclerView parent) {
        if (mOrientation == VERTICAL_LIST) {
            drawVertical(c, parent);
        } else {
            drawHorizontal(c, parent);
        }
    }
    public void drawVertical(Canvas c, RecyclerView parent) {
        final int left = parent.getPaddingLeft();
        final int right = parent.getWidth() - parent.getPaddingRight();
        final int childCount = parent.getChildCount();
        for (int i = 0; i < childCount; i++) {
            final View child = parent.getChildAt(i);
            android.support.v7.widget.RecyclerView v = new android.support.v7.widget.RecyclerView(parent.getContext());
            final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child
                    .getLayoutParams();
            final int top = child.getBottom() + params.bottomMargin;
            final int bottom = top + mDivider.getIntrinsicHeight();
            mDivider.setBounds(left, top, right, bottom);
            mDivider.draw(c);
        }
    }
    public void drawHorizontal(Canvas c, RecyclerView parent) {
        final int top = parent.getPaddingTop();
        final int bottom = parent.getHeight() - parent.getPaddingBottom();
        final int childCount = parent.getChildCount();
        for (int i = 0; i < childCount; i++) {
            final View child = parent.getChildAt(i);
            final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child
                    .getLayoutParams();
            final int left = child.getRight() + params.rightMargin;
            final int right = left + mDivider.getIntrinsicHeight();
            mDivider.setBounds(left, top, right, bottom);
            mDivider.draw(c);
        }
    }
    @Override
    public void getItemOffsets(Rect outRect, int itemPosition, RecyclerView parent) {
        if (mOrientation == VERTICAL_LIST) {
            outRect.set(0, 0, 0, mDivider.getIntrinsicHeight());
        } else {
            outRect.set(0, 0, mDivider.getIntrinsicWidth(), 0);
        }
    }
}

最终效果

ok 到这用RecyclerView实现listView效果就介绍完了，接下来我们介绍一下GridView效果的实现