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Android RecyclerView加载不同布局简单实现

2019-12-12 05:31:57
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前言

关于RecyclerView的使用这里就不在赘述了,相信网上一搜一大把(本人之前的文章也有简单的使用介绍),这次我们讲的是RecyclerView在使用的过程中,有时候会根据不同的位置加载不同的布局的简单实现,这里只是起到抛砖引玉的作用

效果图

设计思想
 •重写RecyclerView.Adapter的getItemViewType(int position),
在此方法中根据不同的position,设置不同的ViewType
 •编写具体的RecyclerView.ViewHolder子类(不同子类对应不同View或Layout)
 •重写RecyclerView.Adapter的onCreateViewHolder(ViewGroup parent,int viewType)
在此方法中根据我们之前设置的ViewType来返回不同的RecyclerView.ViewHolder的子类 

代码

使用RecyclerView需要添加依赖

compile 'com.android.support:recyclerview-v7:24.1.1'

首先是MainActivity布局,很简单的布局

<?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:layout_width="match_parent"  android:layout_height="match_parent"  tools:context="com.example.hfs.recyclerviewloadlayout.MainActivity">  <android.support.v7.widget.RecyclerView    android:id="@+id/recyclerview"    android:layout_width="match_parent"    android:layout_height="match_parent" /></RelativeLayout>

然后是MainActivity代码

package com.example.hfs.recyclerviewloadlayout;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 java.util.ArrayList;import java.util.List;public class MainActivity extends AppCompatActivity {  private RecyclerView mRecyclerView;  @Override  protected void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    setContentView(R.layout.activity_main);    initView();    initData();  }  private void initData() {    List<String> descs = new ArrayList<>();    descs.clear();    List<Integer> images = new ArrayList<>();    images.clear();    for (int i = 1; i < 21; i++) {      descs.add("测试数据" + (i < 10 ? "0" + i : i));    }    images.add(R.mipmap.ic_launcher);    images.add(R.mipmap.ic_launcher);    images.add(R.mipmap.ic_launcher);    images.add(R.mipmap.ic_launcher);    images.add(R.mipmap.ic_launcher);    images.add(R.mipmap.ic_launcher);    images.add(R.mipmap.ic_launcher);    images.add(R.mipmap.ic_launcher);    images.add(R.mipmap.ic_launcher);    images.add(R.mipmap.ic_launcher);    images.add(R.mipmap.ic_launcher);    images.add(R.mipmap.ic_launcher);    images.add(R.mipmap.ic_launcher);    images.add(R.mipmap.ic_launcher);    images.add(R.mipmap.ic_launcher);    images.add(R.mipmap.ic_launcher);    images.add(R.mipmap.ic_launcher);    images.add(R.mipmap.ic_launcher);    images.add(R.mipmap.ic_launcher);    images.add(R.mipmap.ic_launcher);    images.add(R.mipmap.ic_launcher);    MyAdapter adapter = new MyAdapter(MainActivity.this, descs, images);    mRecyclerView.setAdapter(adapter);    RecyclerView.LayoutManager manager = new LinearLayoutManager(MainActivity.this, LinearLayoutManager.VERTICAL, false);    mRecyclerView.setLayoutManager(manager);    mRecyclerView.addItemDecoration(new DividerItemDecoration(MainActivity.this, DividerItemDecoration.VERTICAL_LIST));    adapter.setmOnItemClickListener(new MyAdapter.OnItemClickListener() {      @Override      public void onItemClick(View view, int position) {        Toast.makeText(MainActivity.this, "点击了" + position + "位置", Toast.LENGTH_SHORT).show();      }    });  }  private void initView() {    mRecyclerView= (RecyclerView) findViewById(R.id.recyclerview);  }}

然后是我们的适配器

package com.example.hfs.recyclerviewloadlayout;import android.content.Context;import android.support.v7.widget.RecyclerView;import android.view.View;import android.view.ViewGroup;import android.widget.ImageView;import android.widget.TextView;import java.util.ArrayList;import java.util.List;/** * Created by HFS on 2016/8/24. */public class MyAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {  private Context mContext;  private List<String> descs;  private List<Integer> images;  private List<Object> allList;  private static final int TEXTVIEW_VIEWTYPE = 1;  private static final int IMAGEVIEW_VIEWTYPE = 2;  public interface OnItemClickListener {    void onItemClick(View view, int position);  }  private OnItemClickListener mOnItemClickListener;  public OnItemClickListener getmOnItemClickListener() {    return mOnItemClickListener;  }  public void setmOnItemClickListener(OnItemClickListener mOnItemClickListener) {    this.mOnItemClickListener = mOnItemClickListener;  }  public MyAdapter(Context mContext, List<String> descs, List<Integer> images) {    this.mContext = mContext;    this.descs = descs;    this.images = images;    allList = new ArrayList<>();    allList.clear();    for (int i = 0; i < descs.size(); i++) {      allList.add(descs.get(i));      allList.add(images.get(i));    }  }  @Override  public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {    RecyclerView.ViewHolder holder = getViewHolderByViewType(viewType);    return holder;  }  private RecyclerView.ViewHolder getViewHolderByViewType(int viewType) {    View tv_ItemView = View.inflate(mContext, R.layout.item_tv, null);    View iv_ItemView = View.inflate(mContext, R.layout.item_iv, null);    RecyclerView.ViewHolder holder = null;    switch (viewType) {      case TEXTVIEW_VIEWTYPE:        holder = new MyTextView_ViewHolder(tv_ItemView);        break;      case IMAGEVIEW_VIEWTYPE:        holder = new MyImageView_ViewHolder(iv_ItemView);        break;    }    return holder;  }  @Override  public int getItemViewType(int position) {    int viewType = -1;    int index = position % 2;    switch (index) {      case 0:        viewType = TEXTVIEW_VIEWTYPE;        break;      case 1:        viewType = IMAGEVIEW_VIEWTYPE;        break;    }    return viewType;  }  @Override  public void onBindViewHolder(RecyclerView.ViewHolder holder, final int position) {    if (position % 2 == 0) {      ((MyTextView_ViewHolder) holder).tv.setText(((String) allList.get(position)));      ((MyTextView_ViewHolder) holder).view.setOnClickListener(new View.OnClickListener() {        @Override        public void onClick(View v) {          if (mOnItemClickListener != null) {            mOnItemClickListener.onItemClick(v, position);          }        }      });    } else {      ((MyImageView_ViewHolder) holder).iv.setImageResource(((Integer) allList.get(position)));      ((MyImageView_ViewHolder) holder).view.setOnClickListener(new View.OnClickListener() {        @Override        public void onClick(View v) {          if (mOnItemClickListener != null) {            mOnItemClickListener.onItemClick(v, position);          }        }      });    }  }  @Override  public int getItemCount() {    return allList.size();  }  class MyTextView_ViewHolder extends RecyclerView.ViewHolder {    public View view;    public TextView tv;    public MyTextView_ViewHolder(View itemView) {      super(itemView);      this.view = itemView;      this.tv = (TextView) itemView.findViewById(R.id.tv);    }  }  class MyImageView_ViewHolder extends RecyclerView.ViewHolder {    public View view;    public ImageView iv;    public MyImageView_ViewHolder(View itemView) {      super(itemView);      this.view = itemView;      this.iv = (ImageView) itemView.findViewById(R.id.iv);    }  }}

接着就是我们自定义的DividerItemDecoration

package com.example.hfs.recyclerviewloadlayout;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;/** * Created by HFS on 2016/8/24. */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);      RecyclerView v = new 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);    }  }}

项目地址:https://github.com/Greathfs/RecyclerViewLoadLayout

以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持武林网。

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