? ? ? 當(dāng)我們程序員編寫(xiě)類似聊天的程序時(shí)，總是會(huì)遇到在底部顯示數(shù)據(jù)的listview.html" target="_blank">listview，武林技術(shù)頻道小編在這里給大家推薦ListView實(shí)現(xiàn)聊天列表之處理不同數(shù)據(jù)項(xiàng)，一起來(lái)看看吧！
? ? ? 通常我們用慣的ListView每一項(xiàng)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(jiàn)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(yǔ)音、圖片、視頻等等，他們真的是ListView可以實(shí)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(shí)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(jiǎn)單的情況，但我們只需要了解其中的原理，再?gòu)?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(jìn)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(jiǎn)單，最后，我再將所有代碼一同貼出來(lái)。
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(guò)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(méi)事就不能找你談情說(shuō)愛(ài)嗎？也沒(méi)什么事，看你有沒(méi)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(lái)找虐。"); chat5.setAvatar(BitmapFactory.decodeResource(getResources(), R.drawable.ic_item2)); mDatas.add(chat5); } } 上文是武林技術(shù)頻道小編帶來(lái)的ListView實(shí)現(xiàn)聊天列表之處理不同數(shù)據(jù)項(xiàng)，讓我們一起去學(xué)習(xí)吧，學(xué)習(xí)好編程，可以在項(xiàng)目中實(shí)現(xiàn)很多我們想象不到的東西。新聞熱點(diǎn)
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