类似微信的聊天界面ListView

微信中的ListView有一个特点就是存在许多不同的Item，即并不是平常的ListView，所有的Item布局都是一样的。针对这种情况，Google的Adapter提供了两个方法getItemViewType和getViewTypeCount。通过覆盖这两个方法就可以实现一个ListView中存在多种不同的Layout。实现了更加个性化的ListView效果。我归纳了下微信中的Item可以分为7中。针对这7种Item我对应地写了7中listItem。在getView的时候判断下当前数据对象中需要通过哪种布局来展现，来实时获取布局。

下面看代码：

Message.java

public class Message {

	private int type;//指定是哪种类型
	private String value;//值
	public int getType() {
		return type;
	}
	public void setType(int type) {
		this.type = type;
	}
	public String getValue() {
		return value;
	}
	public void setValue(String value) {
		this.value = value;
	}
}

MainActivity.java:

public class MainActivity extends Activity {

	private ListView lvData;
	
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		
		lvData = (ListView)findViewById(R.id.lv_data);
		
		lvData.setAdapter(getAdapter());
	}

	private BaseAdapter getAdapter(){
		
		return new MyAdapter(this, getMyData());
	}
	
	private List<Message> getMyData(){
		
		List<Message> msgList = new ArrayList<Message>();
		Message msg;
		msg = new Message();
		msg.setType(MyAdapter.VALUE_LEFT_TEXT);
		msg.setValue("食堂真难吃啊");
		msgList.add(msg);
		
		msg = new Message();
		msg.setType(MyAdapter.VALUE_TIME_TIP);
		msg.setValue("2012-12-23 下午2:23");
		msgList.add(msg);
		
		msg = new Message();
		msg.setType(MyAdapter.VALUE_RIGHT_TEXT);
		msg.setValue("我就说食堂的饭难吃吧，你不相信！");
		msgList.add(msg);
		
		msg = new Message();
		msg.setType(MyAdapter.VALUE_LEFT_TEXT);
		msg.setValue("好吧，这次听你的了。");
		msgList.add(msg);
		
		msg = new Message();
		msg.setType(MyAdapter.VALUE_TIME_TIP);
		msg.setValue("2012-12-23 下午2:25");
		msgList.add(msg);
		
		msg = new Message();
		msg.setType(MyAdapter.VALUE_RIGHT_TEXT);
		msg.setValue("就要圣诞了，有什么安排没有？");
		msgList.add(msg);

		msg = new Message();
		msg.setType(MyAdapter.VALUE_LEFT_TEXT);
		msg.setValue("没有啊，你呢？");
		msgList.add(msg);
		
		msg = new Message();
		msg.setType(MyAdapter.VALUE_TIME_TIP);
		msg.setValue("2012-12-23 下午3:25");
		msgList.add(msg);
		
		msg = new Message();
		msg.setType(MyAdapter.VALUE_LEFT_IMAGE);
		msg.setValue("7min");
		msgList.add(msg);
		
		msg = new Message();
		msg.setType(MyAdapter.VALUE_RIGHT_TEXT);
		msg.setValue("高帅富有三宝 木耳 跑车 和名表，" +
				"黑木耳有三宝 美瞳 备胎 黑丝脚 ，穷矮挫有三宝 AV 手纸 射得早 ，女神有三宝 干嘛 呵呵 去洗澡 ，宅男有三宝 Dota 基友 破电脑 " +
				"女屌丝有三宝 虎背 熊腰 眼睛小 ， 女屌丝还有三宝 饼脸 花痴 卖萌照");
		msgList.add(msg);
		
		msg = new Message();
		msg.setType(MyAdapter.VALUE_LEFT_TEXT);
		msg.setValue("碉堡了");
		msgList.add(msg);
		
		msg = new Message();
		msg.setType(MyAdapter.VALUE_LEFT_AUDIO);
		msg.setValue("7min");
		msgList.add(msg);
		
		msg = new Message();
		msg.setType(MyAdapter.VALUE_RIGHT_IMAGE);
		msg.setValue("7min");
		msgList.add(msg);
		
		return msgList;
		
	}
	
	
}

 

下面是最重要的地方：

MyAdapter.java:

public class MyAdapter extends BaseAdapter{

	
	public static final String KEY = "key";
	public static final String VALUE = "value";
	
	public static final int VALUE_TIME_TIP = 0;//7种不同的布局
	public static final int VALUE_LEFT_TEXT = 1;
	public static final int VALUE_LEFT_IMAGE = 2;
	public static final int VALUE_LEFT_AUDIO = 3;
	public static final int VALUE_RIGHT_TEXT = 4;
	public static final int VALUE_RIGHT_IMAGE = 5;
	public static final int VALUE_RIGHT_AUDIO = 6;
	private LayoutInflater mInflater;
	
	private Context context;
	private List<Message> myList;
	public MyAdapter(Context context, List<Message> myList){
		
		this.context = context;
		this.myList = myList;
		
		for(Message msg:myList){
			
			Log.d("myList:", msg.getType()+"");
		}
		
		mInflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
	}
	
	public void addItem(final Message item) {
		myList.add(item);
        notifyDataSetChanged();
    }
	
	@Override
	public int getCount() {
		return myList.size();
	}

	@Override
	public Object getItem(int arg0) {
		return myList.get(arg0);
	}

	@Override
	public long getItemId(int arg0) {
		return arg0;
	}

	@Override
	public View getView(int position, View convertView, ViewGroup arg2) {
		
		Message msg = myList.get(position);
		int type = getItemViewType(position);
		ViewHolder holder = null;
		if(convertView == null){
			
			holder = new ViewHolder();
				switch (type) {
					case VALUE_TIME_TIP:
						
						convertView = mInflater.inflate(R.layout.list_item_time_tip, null);
						holder.tvTimeTip = (TextView)convertView.findViewById(R.id.tv_time_tip);
						holder.tvTimeTip.setText(msg.getValue());
						break;
								//左边
					case VALUE_LEFT_TEXT:
						
						convertView = mInflater.inflate(R.layout.list_item_left_text, null);
						holder.ivLeftIcon = (ImageView)convertView.findViewById(R.id.iv_icon);
						holder.btnLeftText = (Button)convertView.findViewById(R.id.btn_left_text);
						holder.btnLeftText.setText(msg.getValue());
						break;
						
					case VALUE_LEFT_IMAGE:
						
						convertView = mInflater.inflate(R.layout.list_item_left_iamge, null);
						holder.ivLeftIcon = (ImageView)convertView.findViewById(R.id.iv_icon);
						holder.ivLeftImage = (ImageView)convertView.findViewById(R.id.iv_left_image);
						holder.ivLeftImage.setImageResource(R.drawable.test);
						break;
						
					case VALUE_LEFT_AUDIO:
	
						convertView = mInflater.inflate(R.layout.list_item_left_audio, null);
						holder.ivLeftIcon = (ImageView)convertView.findViewById(R.id.iv_icon);
						holder.btnLeftAudio = (Button)convertView.findViewById(R.id.btn_left_audio);
						holder.tvLeftAudioTime = (TextView)convertView.findViewById(R.id.tv_left_audio_time);
						holder.tvLeftAudioTime.setText(msg.getValue());
						break;
								//右边
					case VALUE_RIGHT_TEXT:
						
						convertView = mInflater.inflate(R.layout.list_item_right_text, null);
						holder.ivRightIcon = (ImageView)convertView.findViewById(R.id.iv_icon);
						holder.btnRightText = (Button)convertView.findViewById(R.id.btn_right_text);
						holder.btnRightText.setText(msg.getValue());
						break;
						
					case VALUE_RIGHT_IMAGE:
						
						convertView = mInflater.inflate(R.layout.list_item_right_iamge, null);
						holder.ivRightIcon = (ImageView)convertView.findViewById(R.id.iv_icon);
						holder.ivRightImage = (ImageView)convertView.findViewById(R.id.iv_right_image);
						holder.ivRightImage.setImageResource(R.drawable.test);
						break;
						
					case VALUE_RIGHT_AUDIO:
	
						convertView = mInflater.inflate(R.layout.list_item_right_audio, null);
						holder.ivRightIcon = (ImageView)convertView.findViewById(R.id.iv_icon);
						holder.btnRightAudio = (Button)convertView.findViewById(R.id.btn_right_audio);
						holder.tvRightAudioTime = (TextView)convertView.findViewById(R.id.tv_right_audio_time);
						holder.tvRightAudioTime.setText(msg.getValue());
						break;
						
					default:
						break;
				}
				convertView.setTag(holder);
			}else{
				holder = (ViewHolder)convertView.getTag();
			}
			return convertView;
		}
	
	/**
	 * 根据数据源的position返回需要显示的的layout的type
	 * 
	 * */
	@Override
	public int getItemViewType(int position) {
		
		Message msg = myList.get(position);
		int type = msg.getType();
		Log.e("TYPE:", ""+type);
		return type;
	}

	/**
	 * 返回所有的layout的数量
	 * 
	 * */
	@Override
	public int getViewTypeCount() {
		return 7;
	}
	
	class ViewHolder{
		
		private TextView tvTimeTip;//时间
		
		private ImageView ivLeftIcon;//左边的头像
		private Button btnLeftText;//左边的文本
		private ImageView ivLeftImage;//左边的图像
		private Button btnLeftAudio;//左边的声音
		private TextView tvLeftAudioTime;//左边的声音时间
		
		private ImageView ivRightIcon;//右边的头像
		private Button btnRightText;//右边的文本
		private ImageView ivRightImage;//右边的图像
		private Button btnRightAudio;//右边的声音
		private TextView tvRightAudioTime;//右边的声音时间
	}

}

在getView()的时候通过switch判断当前一条数据需要使用的是哪种布局，实时进行加载。

getItemViewType() 和getViewTypeCount() 这两个方法起到的作用是循环回收利用不同的布局，起到了优化的作用！这是不同于平时使用Adapter的地方。

效果如下：

项目地址：

https://github.com/michaelye/WeiXinListView