Android RecyclerView简单入门学习

理解：onCreateViewHolder：是返回视图的，不含有业务数据

           onBindViewHolder：可以在这里面添加数据

RecyleView统一了ListView,GridView和和瀑布流这几种形式，提供了强大的diliver自定义，删除和添加动画功能，不错。

还可以把竖的变成横的，一句话的事情

详细情况向大牛学习：http://blog.csdn.net/lmj623565791/article/details/45059587

android.R.attr.listDivider：这个是安卓自带的一个属性，就好像

<declare-styleable name="MyView">
        <attr name="textColor111" format="color" />
    </declare-styleable>

里面的textColor111

<style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
        <item name="android:listDivider">@drawable/divider_bg</item>
    </style>

这句话是的意思应该是一个安卓定义的样式，这个样式给予安卓的andriod:listDivider这个属性赋予了一个值

package com.example.lenovo.myapplication;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.support.v7.widget.DefaultItemAnimator;import android.support.v7.widget.GridLayoutManager;import android.support.v7.widget.LinearLayoutManager;import android.support.v7.widget.RecyclerView;import android.support.v7.widget.StaggeredGridLayoutManager;import android.view.LayoutInflater;import android.view.Menu;import android.view.MenuItem;import android.view.View;import android.view.ViewGroup;import android.widget.TextView;import android.widget.Toast;import java.util.ArrayList;import java.util.List;public class MainActivity extends AppCompatActivity {    private RecyclerView mRecyclerView;    private List<String> mDatas;    private HomeAdapter mAdapter;    private StaggeredHomeAdapter staggeredHomeAdapter;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        initData();        mRecyclerView = (RecyclerView) findViewById(R.id.id_recyclerview);        /**listview形式的*/     //   mRecyclerView.setLayoutManager(new LinearLayoutManager(this));        /**datagrid形式的*/      //  mRecyclerView.setLayoutManager(new GridLayoutManager(this, 4));        //瀑布流形式的        mRecyclerView.setLayoutManager(new StaggeredGridLayoutManager(4, StaggeredGridLayoutManager.HORIZONTAL));     //   mRecyclerView.addItemDecoration(new DividerItemDecoration(this,DividerItemDecoration.VERTICAL_LIST)        mRecyclerView.addItemDecoration(new DividerGridItemDecoration(this));  //      mRecyclerView.setAdapter(mAdapter = new HomeAdapter());        staggeredHomeAdapter=new StaggeredHomeAdapter(this,mDatas);        staggeredHomeAdapter.setOnItemClickLitener(new StaggeredHomeAdapter.OnItemClickLitener() {            @Override            public void onItemClick(View view, int position) {                Toast.makeText(MainActivity.this, position + " click",                        Toast.LENGTH_SHORT).show();            }            @Override            public void onItemLongClick(View view, int position) {                Toast.makeText(MainActivity.this, position + " long click",                        Toast.LENGTH_SHORT).show();            }        });        mRecyclerView.setAdapter(staggeredHomeAdapter);        // 设置item动画        mRecyclerView.setItemAnimator(new DefaultItemAnimator());    }    protected void initData()    {        mDatas = new ArrayList<String>();        for (int i = 'A'; i < 'z'; i++)        {            mDatas.add("" + (char) i);        }    }    class HomeAdapter extends RecyclerView.Adapter<HomeAdapter.MyViewHolder>    {        /**         *获取ITEM视图，但是没有往里面加数据         * @param parent         * @param viewType         * @return         */        @Override        public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType)        {            MyViewHolder holder = new MyViewHolder(LayoutInflater.from(MainActivity.this).inflate(R.layout.item_home, parent, false));            return holder;        }        /**         * 往ITEM视图里添加数据         * @param holder         * @param position         */        @Override        public void onBindViewHolder(MyViewHolder holder, int position)        {            holder.tv.setText(mDatas.get(position));        }        @Override        public int getItemCount()        {            return mDatas.size();        }        class MyViewHolder extends RecyclerView.ViewHolder        {            TextView tv;            public MyViewHolder(View view)            {                super(view);                tv = (TextView) view.findViewById(R.id.id_num);            }        }    }    @Override    public boolean onCreateOptionsMenu(Menu menu)    {        getMenuInflater().inflate(R.menu.main, menu);        return super.onCreateOptionsMenu(menu);    }    @Override    public boolean onOptionsItemSelected(MenuItem item)    {        switch (item.getItemId())        {            case R.id.id_action_add:                staggeredHomeAdapter.addData(1);                break;            case R.id.id_action_delete:                staggeredHomeAdapter.removeData(1);                break;        }        return true;    }}

package com.example.lenovo.myapplication;/** * Created by lenovo on 2015/10/25. *//* * Copyright (C) 2014 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * limitations under the License. */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.support.v7.widget.RecyclerView.State;import android.util.Log;import android.view.View;/** * 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 {    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);        }    }}

package com.example.lenovo.myapplication;/** * Created by lenovo on 2015/10/25. */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.GridLayoutManager;import android.support.v7.widget.RecyclerView;import android.support.v7.widget.RecyclerView.LayoutManager;import android.support.v7.widget.RecyclerView.State;import android.support.v7.widget.StaggeredGridLayoutManager;import android.view.View;/** * * @author zhy * */public class DividerGridItemDecoration extends RecyclerView.ItemDecoration{    private static final int[] ATTRS = new int[] { android.R.attr.listDivider };    private Drawable mDivider;    public DividerGridItemDecoration(Context context)    {        final TypedArray a = context.obtainStyledAttributes(ATTRS);        mDivider = a.getDrawable(0);        a.recycle();    }    @Override    public void onDraw(Canvas c, RecyclerView parent, State state)    {        drawHorizontal(c, parent);        drawVertical(c, parent);    }    private int getSpanCount(RecyclerView parent)    {        // 列数        int spanCount = -1;        LayoutManager layoutManager = parent.getLayoutManager();        if (layoutManager instanceof GridLayoutManager)        {            spanCount = ((GridLayoutManager) layoutManager).getSpanCount();        } else if (layoutManager instanceof StaggeredGridLayoutManager)        {            spanCount = ((StaggeredGridLayoutManager) layoutManager)                    .getSpanCount();        }        return spanCount;    }    public void drawHorizontal(Canvas c, RecyclerView parent)    {        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.getLeft() - params.leftMargin;            final int right = child.getRight() + params.rightMargin                    + mDivider.getIntrinsicWidth();            final int top = child.getBottom() + params.bottomMargin;            final int bottom = top + mDivider.getIntrinsicHeight();            mDivider.setBounds(left, top, right, bottom);            mDivider.draw(c);        }    }    public void drawVertical(Canvas c, RecyclerView parent)    {        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 top = child.getTop() - params.topMargin;            final int bottom = child.getBottom() + params.bottomMargin;            final int left = child.getRight() + params.rightMargin;            final int right = left + mDivider.getIntrinsicWidth();            mDivider.setBounds(left, top, right, bottom);            mDivider.draw(c);        }    }    private boolean isLastColum(RecyclerView parent, int pos, int spanCount,                                int childCount)    {        LayoutManager layoutManager = parent.getLayoutManager();        if (layoutManager instanceof GridLayoutManager)        {            if ((pos + 1) % spanCount == 0)// 如果是最后一列，则不需要绘制右边            {                return true;            }        } else if (layoutManager instanceof StaggeredGridLayoutManager)        {            int orientation = ((StaggeredGridLayoutManager) layoutManager)                    .getOrientation();            if (orientation == StaggeredGridLayoutManager.VERTICAL)            {                if ((pos + 1) % spanCount == 0)// 如果是最后一列，则不需要绘制右边                {                    return true;                }            } else            {                childCount = childCount - childCount % spanCount;                if (pos >= childCount)// 如果是最后一列，则不需要绘制右边                    return true;            }        }        return false;    }    private boolean isLastRaw(RecyclerView parent, int pos, int spanCount,                              int childCount)    {        LayoutManager layoutManager = parent.getLayoutManager();        if (layoutManager instanceof GridLayoutManager)        {            childCount = childCount - childCount % spanCount;            if (pos >= childCount)// 如果是最后一行，则不需要绘制底部                return true;        } else if (layoutManager instanceof StaggeredGridLayoutManager)        {            int orientation = ((StaggeredGridLayoutManager) layoutManager)                    .getOrientation();            // StaggeredGridLayoutManager 且纵向滚动            if (orientation == StaggeredGridLayoutManager.VERTICAL)            {                childCount = childCount - childCount % spanCount;                // 如果是最后一行，则不需要绘制底部                if (pos >= childCount)                    return true;            } else            // StaggeredGridLayoutManager 且横向滚动            {                // 如果是最后一行，则不需要绘制底部                if ((pos + 1) % spanCount == 0)                {                    return true;                }            }        }        return false;    }    @Override    public void getItemOffsets(Rect outRect, int itemPosition,                               RecyclerView parent)    {        int spanCount = getSpanCount(parent);        int childCount = parent.getAdapter().getItemCount();        if (isLastRaw(parent, itemPosition, spanCount, childCount))// 如果是最后一行，则不需要绘制底部        {            outRect.set(0, 0, mDivider.getIntrinsicWidth(), 0);        } else if (isLastColum(parent, itemPosition, spanCount, childCount))// 如果是最后一列，则不需要绘制右边        {            outRect.set(0, 0, 0, mDivider.getIntrinsicHeight());        } else        {            outRect.set(0, 0, mDivider.getIntrinsicWidth(),                    mDivider.getIntrinsicHeight());        }    }}

package com.example.lenovo.myapplication;import android.support.v7.widget.RecyclerView;import android.view.View;import android.widget.TextView;import java.util.ArrayList;        import java.util.List;        import android.content.Context;        import android.support.v7.widget.RecyclerView;        import android.support.v7.widget.RecyclerView.ViewHolder;        import android.view.LayoutInflater;        import android.view.View;        import android.view.View.OnClickListener;        import android.view.View.OnLongClickListener;        import android.view.ViewGroup;        import android.view.ViewGroup.LayoutParams;        import android.widget.TextView;class StaggeredHomeAdapter extends        RecyclerView.Adapter<StaggeredHomeAdapter.MyViewHolder>{    private List<String> mDatas;    private LayoutInflater mInflater;    private List<Integer> mHeights;    public interface OnItemClickLitener    {        void onItemClick(View view, int position);        void onItemLongClick(View view, int position);    }    private OnItemClickLitener mOnItemClickLitener;    public void setOnItemClickLitener(OnItemClickLitener mOnItemClickLitener)    {        this.mOnItemClickLitener = mOnItemClickLitener;    }    public StaggeredHomeAdapter(Context context, List<String> datas)    {        mInflater = LayoutInflater.from(context);        mDatas = datas;        mHeights = new ArrayList<Integer>();        for (int i = 0; i < mDatas.size(); i++)        {            mHeights.add( (int) (100 + Math.random() * 300));        }    }    @Override    public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType)    {        MyViewHolder holder = new MyViewHolder(mInflater.inflate(                R.layout.item_staggered_home, parent, false));        return holder;    }    @Override    public void onBindViewHolder(final MyViewHolder holder, final int position)    {        LayoutParams lp = holder.tv.getLayoutParams();        lp.height = mHeights.get(position);        holder.tv.setLayoutParams(lp);        holder.tv.setText(mDatas.get(position));        // 如果设置了回调，则设置点击事件        if (mOnItemClickLitener != null)        {            holder.itemView.setOnClickListener(new OnClickListener()            {                @Override                public void onClick(View v)                {                    int positionT = holder.getPosition();                    mOnItemClickLitener.onItemClick(holder.itemView,positionT );                }            });            holder.itemView.setOnLongClickListener(new OnLongClickListener()            {                @Override                public boolean onLongClick(View v)                {                    int positionT = holder.getPosition();                    mOnItemClickLitener.onItemLongClick(holder.itemView, position);                    removeData(position);                    return false;                }            });        }    }    @Override    public int getItemCount()    {        return mDatas.size();    }    public void addData(int position)    {        mDatas.add(position, "Insert One");        mHeights.add( (int) (100 + Math.random() * 300));        notifyItemInserted(position);    }    public void removeData(int position)    {        mDatas.remove(position);        notifyItemRemoved(position);    }    class MyViewHolder extends RecyclerView.ViewHolder    {        TextView tv;        public MyViewHolder(View view)        {            super(view);            tv = (TextView) view.findViewById(R.id.id_num);        }    }}