RecyclerView 使用方法

1.加依赖：

compile 'com.android.support:recyclerview-v7:23.2.0'

2.activity中布局如下：

<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".activity.MainActivity">

    <android.support.v7.widget.RecyclerView
        android:id="@+id/recyclerview"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        />
</RelativeLayout>

3.item布局如下：

4.建MyDecoration类，做一些辅助工作：

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;

public class MyDecoration extends RecyclerView.ItemDecoration {
    private Context mContext;
    private Drawable mDivider;
    private int mOrientation;
    public static final int HORIZONTAL_LIST = LinearLayoutManager.HORIZONTAL;
    public static final int VERTICAL_LIST = LinearLayoutManager.VERTICAL;

    //我们通过获取系统属性中的listDivider来添加，在系统中的AppTheme中设置
    public static final int[] ATRRS = new int[]{
            android.R.attr.listDivider
    };

    public MyDecoration(Context context, int orientation) {
        this.mContext = context;
        final TypedArray ta = context.obtainStyledAttributes(ATRRS);
        this.mDivider = ta.getDrawable(0);
        ta.recycle();
        setOrientation(orientation);
    }

    //设置屏幕的方向
    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, RecyclerView.State state) {
        if (mOrientation == HORIZONTAL_LIST){
            drawVerticalLine(c, parent, state);
        }else {
            drawHorizontalLine(c, parent, state);
        }
    }

    //画横线, 这里的parent其实是显示在屏幕显示的这部分
    public void drawHorizontalLine(Canvas c, RecyclerView parent, RecyclerView.State state){
        int left = parent.getPaddingLeft();
        int right = parent.getWidth() - parent.getPaddingRight();
        final int childCount = parent.getChildCount();
        for (int i = 0; i < childCount; i++){
            final View child = parent.getChildAt(i);

            //获得child的布局信息
            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);
            //Log.d("wnw", left + " " + top + " "+right+"   "+bottom+" "+i);
        }
    }

    //画竖线
    public void drawVerticalLine(Canvas c, RecyclerView parent, RecyclerView.State state){
        int top = parent.getPaddingTop();
        int bottom = parent.getHeight() - parent.getPaddingBottom();
        final int childCount = parent.getChildCount();
        for (int i = 0; i < childCount; i++){
            final View child = parent.getChildAt(i);

            //获得child的布局信息
            final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams)child.getLayoutParams();
            final int left = child.getRight() + params.rightMargin;
            final int right = left + mDivider.getIntrinsicWidth();
            mDivider.setBounds(left, top, right, bottom);
            mDivider.draw(c);
        }
    }

    //由于Divider也有长宽高，每一个Item需要向下或者向右偏移
    @Override
    public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
        if(mOrientation == HORIZONTAL_LIST){
            //画横线，就是往下偏移一个分割线的高度
            outRect.set(0, 0, 0, mDivider.getIntrinsicHeight());
        }else {
            //画竖线，就是往右偏移一个分割线的宽度
            outRect.set(0, 0, mDivider.getIntrinsicWidth(), 0);
        }
    }
}

5.建MyAdapter,用于适配RecyclerView：

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

import com.bawei.recyclerview.R;
import com.bawei.recyclerview.activity.MainActivity;

import java.util.List;

public class MyAdapter extends RecyclerView.Adapter<MyAdapter.MyViewHolder> {
    Context context;
    List<String> data;
    //声明接口
    public OnItemClickListener itemClickListener;
    public OnItemLongClickListener itemLongClickListener;

    //定义条目点击事件
    public interface OnItemClickListener {
        void onItemClick(View view, int position);
    }

    //定义条目的长按事件
    public interface OnItemLongClickListener {
        void onItemLongClick(View view, int position);
    }

    //对外提供两个访问的set方法
    public void setOnItemClickListener(OnItemClickListener itemClickListener) {
        this.itemClickListener = itemClickListener;
    }

    public void setOnItemLongClickListener(OnItemLongClickListener itemLongClickListener) {
        this.itemLongClickListener = itemLongClickListener;
    }

    public MyAdapter(Context context, List<String> data) {
        this.context = context;
        this.data = data;
    }

    //把view绑定给ViewHolder
    @Override
    public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View view = View.inflate(context, R.layout.item, null);
        final MyViewHolder holder = new MyViewHolder(view);
        view.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                int position = holder.getLayoutPosition();
                //注册点击监听
                if (itemClickListener != null) {
                    itemClickListener.onItemClick(v, position);
                }
            }
        });
        view.setOnLongClickListener(new View.OnLongClickListener() {
            @Override
            public boolean onLongClick(View v) {
                int position = holder.getLayoutPosition();
                if (itemLongClickListener != null) {
                    //注册长按监听
                    itemLongClickListener.onItemLongClick(v, position);
                }
                //事件消费，不继续传递
                return true;
            }
        });
        return holder;
    }

    //把数据赋值给view控件
    @Override
    public void onBindViewHolder(MyViewHolder holder, int position) {
        holder.tv_title.setText(data.get(position));

    }

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

    //自定义ViewHolder 持有item界面的所有元素
    public class MyViewHolder extends RecyclerView.ViewHolder {

        private final TextView tv_title;

        public MyViewHolder(View itemView) {
            super(itemView);
            tv_title = (TextView) itemView.findViewById(R.id.tv_title);
        }
    }
}

6.MainActivity中代码如下：

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.View;
import android.widget.Toast;

import com.bawei.recyclerview.R;
import com.bawei.recyclerview.adapter.MyAdapter;
import com.bawei.recyclerview.view.MyDecoration;

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

public class MainActivity extends AppCompatActivity {
    private List<String> data = new ArrayList<>();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        //数据源
        for (int i = 0; i < 20; i++) {
            data.add("条目：" + i);
        }

        //找控件
        RecyclerView recyclerView = (RecyclerView) findViewById(R.id.recyclerview);
        //设置布局管理器
        LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this);
        recyclerView.setLayoutManager(linearLayoutManager);
        //添加华丽的分割线
        MyDecoration decoration = new MyDecoration(this, MyDecoration.VERTICAL_LIST);
        recyclerView.addItemDecoration(decoration);
        MyAdapter adapter = new MyAdapter(this, data);
        recyclerView.setAdapter(adapter);
        adapter.setOnItemClickListener(new MyAdapter.OnItemClickListener() {
            @Override
            public void onItemClick(View view, int position) {
                Toast.makeText(MainActivity.this, "条目的点击监听：" + position, Toast.LENGTH_SHORT).show();
            }
        });
        adapter.setOnItemLongClickListener(new MyAdapter.OnItemLongClickListener() {
            @Override
            public void onItemLongClick(View view, int position) {
                Toast.makeText(MainActivity.this, "条目的长按监听：" + position, Toast.LENGTH_SHORT).show();

            }
        });

    }
}

RecyclerView 使用方法

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