Android RecyclerView学习（一） 实现Lis

1.Android Studio中使用RecyclerView控件

build.gradle添加依赖

dependencies {
    compile 'com.android.support:recyclerview-v7:21.0.0'
}

2.RecyclerView 实现ListView效果

效果图：

RecyclerView实现ListView效果图.gif

实现代码：

MainActivity类

package cn.xz.test;

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

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

public class MainActivity extends AppCompatActivity {


    private RecyclerView recyclerView;
    private List<String> mDatas;
    private RecyclerViewAdapter mRecyclerViewAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        this.recyclerView = (RecyclerView) this.findViewById(R.id.recyclerView);
        this.initData();
        this.mRecyclerViewAdapter = new RecyclerViewAdapter(this, this.mDatas);
        this.recyclerView.setLayoutManager(new LinearLayoutManager(this));
        this.recyclerView.setAdapter(this.mRecyclerViewAdapter);
    }

    private void initData(){
        this.mDatas = new ArrayList<>();
        for(int i=0; i<=49; i++){
            this.mDatas.add("第" +  i + "行");
        }
    }

}

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/activity_main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="cn.xz.test.MainActivity">

    <android.support.v7.widget.RecyclerView
        android:id="@+id/recyclerView"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:divider="#ffff0000"
        android:dividerHeight="10dp" >

    </android.support.v7.widget.RecyclerView>



</RelativeLayout>

item_recycler_view.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="match_parent"
    android:background="#44ff0000"
    android:orientation="vertical">

    <TextView
        android:id="@+id/tv"
        android:layout_width="match_parent"
        android:layout_height="50dp"
        android:gravity="center"
        android:text="1"/>
    
</LinearLayout>

RecyclerViewAdapter类

package cn.xz.test;

import android.app.Activity;
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;

/**
 * Created by Eddie on 2017/6/17.
 */

public class RecyclerViewAdapter extends RecyclerView.Adapter<RecyclerViewAdapter.MyViewHolder> {


    private Activity mActivity;
    private List<String> mDatas;

    public RecyclerViewAdapter(Activity mActivity, List<String> mDatas) {
        this.mActivity = mActivity;
        this.mDatas = mDatas;
    }

    @Override
    public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        MyViewHolder holder = new MyViewHolder(LayoutInflater.from(this.mActivity).inflate(R.layout.item_recycler_view, parent, false));
        return holder;
    }

    @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 itemView) {
            super(itemView);
            this.tv = (TextView) itemView.findViewById(R.id.tv);
        }
    }
}

添加分割线

效果图：

RecyclerView实现ListView添加分割线效果图.gif

实现代码：

this.recyclerView.addItemDecoration(new DividerItemDecoration(this, LinearLayoutManager.VERTICAL));

DividerItemDecoration类

package cn.xz.test;

/*
 * 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.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) {
        Log.v("recyclerview - itemdecoration", "onDraw()");

        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);
            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);
        }
    }
}

自定义分割线

效果图：

RecyclerView实现ListView添加自定义分割线效果图.gif

实现代码：

this.recyclerView.addItemDecoration(new DividerItemDecoration(this, LinearLayoutManager.VERTICAL));

DividerItemDecoration类

package cn.xz.test;

/*
 * 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.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Rect;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.util.Log;
import android.util.TypedValue;
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 {


    public static final int HORIZONTAL_LIST = LinearLayoutManager.HORIZONTAL;

    public static final int VERTICAL_LIST = LinearLayoutManager.VERTICAL;

    private Paint mPaint;

    private int mItemSize = 2 ;

    private int mOrientation;

    public DividerItemDecoration(Context context, int orientation) {
        setOrientation(orientation);
        mItemSize = (int) TypedValue.applyDimension(mItemSize, TypedValue.COMPLEX_UNIT_DIP,context.getResources().getDisplayMetrics());
        mPaint = new Paint(Paint.ANTI_ALIAS_FLAG) ;
        mPaint.setColor(Color.BLUE);
        mPaint.setStyle(Paint.Style.FILL);
    }

    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) {
        Log.v("recyclerview - itemdecoration", "onDraw()");

        if (mOrientation == VERTICAL_LIST) {
            drawVertical(c, parent);
        } else {
            drawHorizontal(c, parent);
        }

    }


    public void drawVertical(Canvas canvas, 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);
            final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams();
            final int top = child.getBottom() + params.bottomMargin;
            final int bottom = top + mItemSize ;
            canvas.drawRect(left,top,right,bottom,mPaint);
        }
    }

    public void drawHorizontal(Canvas canvas, 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 + mItemSize ;
            canvas.drawRect(left,top,right,bottom,mPaint);
        }
    }

    @Override
    public void getItemOffsets(Rect outRect, int itemPosition, RecyclerView parent) {
        if (mOrientation == VERTICAL_LIST) {
            outRect.set(0, 0, 0, mItemSize);
        } else {
            outRect.set(0, 0, mItemSize, 0);
        }
    }
}