ListView實現(xiàn)聊天列表之處理不同數(shù)據(jù)項

發(fā)布時間：2020-10-17 07:22:12 來源：腳本之家閱讀：127 作者：Homilier 欄目：移動開發(fā)

通常我們用慣的ListView每一項的布局都是相同的，只是控件所綁定的數(shù)據(jù)不同。但單單只是如此并不能滿足我們某些特殊需求，比如我們常見的QQ、微信的聊天列表，除了有左右之分外，內(nèi)容更是有很大區(qū)別，有文字、語音、圖片、視頻等等，他們真的是ListView可以實現(xiàn)的嗎？答案是肯定的，只要我們做一下類型區(qū)別即可。

實現(xiàn)效果如下所示：

大家不要在意布局，這里為了方便就隨意了。大家可以看到，這里有兩種布局，一種頭像在左，一種頭像在右，雖然這是一種簡單的情況，但我們只需要了解其中的原理，再復(fù)雜的情況都可以迎刃而解。
我們只要將每一種布局劃為一種類型進行區(qū)分，根據(jù)我們所區(qū)分的類型在我們自定義的Adapter中加載不同布局即可，代碼如下所示：

if (bean.getType() == 1) { 
      convertView = mInflater.inflate(R.layout.item_chat_left, null); 
      holder.mIvAvatar = (ImageView) convertView.findViewById(R.id.iv_chatLeftItem_avatar); 
      holder.mTvContent = (TextView) convertView.findViewById(R.id.tv_chatLeftItem_content); 
  } else if (bean.getType() == 2) { 
      convertView = mInflater.inflate(R.layout.item_chat_right, null); 
      holder.mIvAvatar = (ImageView) convertView.findViewById(R.id.iv_chatRightItem_avatar); 
      holder.mTvContent = (TextView) convertView.findViewById(R.id.tv_chatRightItem_content); 
  }

是不是發(fā)現(xiàn)很簡單，最后，我再將所有代碼一同貼出來。

item_chat_left.xml

<?xml version="1.0" encoding="utf-8"?> 
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 
  android:layout_width="match_parent" 
  android:layout_height="wrap_content" 
  android:padding="6dp" > 
 
  <ImageView 
    android:id="@+id/iv_chatLeftItem_avatar" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:background="#dd00f0" 
    android:src="@drawable/ic_launcher" /> 
 
  <TextView 
    android:id="@+id/tv_chatLeftItem_content" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:textSize="16sp" 
    android:padding="16dp" 
    android:layout_toRightOf="@id/iv_chatLeftItem_avatar" 
    android:background="@drawable/qfav_list_bubble_nor" 
    android:layout_marginRight="64dp" 
    android:gravity="center_vertical" /> 
 
</RelativeLayout>

item_chat_right.xml

<?xml version="1.0" encoding="utf-8"?> 
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 
  android:layout_width="match_parent" 
  android:layout_height="wrap_content" 
  android:padding="6dp" > 
   
  <ImageView 
    android:id="@+id/iv_chatRightItem_avatar" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:layout_alignParentRight="true" 
    android:background="#ddf000" 
    android:src="@drawable/ic_launcher" /> 
   
  <TextView 
    android:id="@+id/tv_chatRightItem_content" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:textSize="16sp" 
    android:padding="16dp" 
    android:layout_toLeftOf="@id/iv_chatRightItem_avatar" 
    android:background="@drawable/skin_aio_user_bubble_pressed" 
    android:layout_marginLeft="64dp" 
    android:gravity="center_vertical" /> 
   
</RelativeLayout>

activity_chat.xml

<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="${relativePackage}.${activityClass}" > 
 
  <ListView 
    android:id="@+id/lv_content" 
    android:layout_width="match_parent" 
    android:layout_height="wrap_content" 
    android:scrollbars="none" 
    android:divider="@null" 
    android:listSelector="@android:color/transparent" > 
  </ListView> 
 
</RelativeLayout>

ChatItemBean.java

import android.graphics.Bitmap; 
 
public class ChatItemBean { 
  private int type; 
  private String content; 
  private Bitmap avatar; 
  public int getType() { 
    return type; 
  } 
  public void setType(int type) { 
    this.type = type; 
  } 
  public String getContent() { 
    return content; 
  } 
  public void setContent(String content) { 
    this.content = content; 
  } 
  public Bitmap getAvatar() { 
    return avatar; 
  } 
  public void setAvatar(Bitmap avatar) { 
    this.avatar = avatar; 
  } 
}

ChatLVAdapter.java

import java.util.List; 
 
import android.content.Context; 
import android.view.LayoutInflater; 
import android.view.View; 
import android.view.ViewGroup; 
import android.widget.BaseAdapter; 
import android.widget.ImageView; 
import android.widget.TextView; 
 
public class ChatLVAdapter extends BaseAdapter { 
 
  private List<ChatItemBean> mDatas; 
  private LayoutInflater mInflater; 
   
  public ChatLVAdapter(Context context, List<ChatItemBean> datas) { 
    this.mInflater = LayoutInflater.from(context); 
    this.mDatas = datas; 
  } 
   
  @Override 
  public int getCount() { 
    return mDatas.size(); 
  } 
 
  @Override 
  public Object getItem(int position) { 
    return mDatas.get(position); 
  } 
 
  @Override 
  public long getItemId(int position) { 
    return position; 
  } 
 
  @Override 
  public View getView(int position, View convertView, ViewGroup parent) { 
    ViewHolder holder = null; 
    ChatItemBean bean = mDatas.get(position); 
    if (convertView == null) { 
      holder = new ViewHolder(); 
      if (bean.getType() == 1) { 
        convertView = mInflater.inflate(R.layout.item_chat_left, null); 
        holder.mIvAvatar = (ImageView) convertView.findViewById(R.id.iv_chatLeftItem_avatar); 
        holder.mTvContent = (TextView) convertView.findViewById(R.id.tv_chatLeftItem_content); 
      } else if (bean.getType() == 2) { 
        convertView = mInflater.inflate(R.layout.item_chat_right, null); 
        holder.mIvAvatar = (ImageView) convertView.findViewById(R.id.iv_chatRightItem_avatar); 
        holder.mTvContent = (TextView) convertView.findViewById(R.id.tv_chatRightItem_content); 
      } 
      convertView.setTag(holder); 
    } else { // 通過tag找到緩存的布局 
      holder = (ViewHolder) convertView.getTag(); 
    } 
    holder.mIvAvatar.setImageBitmap(bean.getAvatar()); 
    holder.mTvContent.setText(bean.getContent()); 
     
    return convertView; 
  } 
   
  public final class ViewHolder { 
    public ImageView mIvAvatar; 
    public TextView mTvContent; 
  }

ChatActivity.java

import java.util.ArrayList; 
import java.util.List; 
 
import android.app.Activity; 
import android.graphics.BitmapFactory; 
import android.os.Bundle; 
import android.widget.ListView; 
 
public class ChatActivity extends Activity { 
  private ListView mLv; 
  private List<ChatItemBean> mDatas ; 
  private ChatLVAdapter mAdapter; 
   
  @Override 
  protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_chat); 
     
    mLv = (ListView) findViewById(R.id.lv_content); 
 
    initData(); 
    mAdapter = new ChatLVAdapter(this, mDatas); 
    mLv.setAdapter(mAdapter); 
  } 
 
  private void initData() { 
    mDatas = new ArrayList<ChatItemBean>(); 
    ChatItemBean chat1 = new ChatItemBean(); 
    chat1.setType(1); 
    chat1.setContent("早啊！"); 
    chat1.setAvatar(BitmapFactory.decodeResource(getResources(), R.drawable.ic_item1)); 
    mDatas.add(chat1); 
    ChatItemBean chat2 = new ChatItemBean(); 
    chat2.setType(2); 
    chat2.setContent("早！一大早找我有啥事？"); 
    chat2.setAvatar(BitmapFactory.decodeResource(getResources(), R.drawable.ic_item2)); 
    mDatas.add(chat2); 
    ChatItemBean chat3 = new ChatItemBean(); 
    chat3.setType(1); 
    chat3.setContent("沒事就不能找你談情說愛嗎？也沒什么事，看你有沒有在擼代碼。"); 
    chat3.setAvatar(BitmapFactory.decodeResource(getResources(), R.drawable.ic_item1)); 
    mDatas.add(chat3); 
    ChatItemBean chat4 = new ChatItemBean(); 
    chat4.setType(2); 
    chat4.setContent("算了吧，別找我！我害怕。"); 
    chat4.setAvatar(BitmapFactory.decodeResource(getResources(), R.drawable.ic_item2)); 
    mDatas.add(chat4); 
    ChatItemBean chat5 = new ChatItemBean(); 
    chat5.setType(2); 
    chat5.setContent("都被代碼擼慘了，我哪敢一早起來找虐。"); 
    chat5.setAvatar(BitmapFactory.decodeResource(getResources(), R.drawable.ic_item2)); 
    mDatas.add(chat5); 
  } 
}

以上就是本文的全部內(nèi)容，希望對大家的學(xué)習(xí)有所幫助，也希望大家多多支持億速云。

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ListView實現(xiàn)聊天列表之處理不同數(shù)據(jù)項

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