ListViewには、複数のitemレイアウトがあります.

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転載先:http://blog.csdn.net/xyz_lmn/article/details/13745489
 
この文章の効果もよく見られますが、微信、whatsapp、易信、米聊など、さまざまな通信アプリケーションの会話リストはこのような方法です.私たちのこの文章も思い出として、簡単なメモを形成する権利があります.この記事は、2009年のGoogle IOの《TurboChargeYourUI-How to make your AndroidUI fast and efficient」と2010年のGoogle IOの《The World of List View》を参考にしています.2009年のGoogle IOの資料はまだ最前線で、androidの開発資料は少なく、最も重要なのはgoogleが発表した様々な資料を参考にすることです.
 
《TurboChargeYourUI-How to make your AndroidUI fast and efficient》でlistviewの性能を向上させる方法を紹介し、listviewのロード速度を最適化した.ここのitemは単一レイアウトを使用しており、viewの再利用や回収が可能であるが、複数種類のレイアウトファイルの場合はどうするのか、上記の方法を再利用するとviewの再利用に問題が発生し、Androidで使用されているBaseAdapterは複数のレイアウトファイルを解決する再利用方法を提供している.
 
1)getViewType Count()を書き換える–このメソッドは、複数の異なるレイアウトを返します.
2)getItemView(int)の書き換え–positionに従って対応するItemを返す
3)view itemのタイプに応じてgetViewで正しいconvertViewを作成し、再利用すると現在必要なタイプに応じて対応するタイプのconvertViewを返す
 
 
 
/**
 *       getItemViewType getViewTypeCount     ,
 * 
 * */
public class ChatAdapter extends BaseAdapter {

	public static final String KEY = "key";
	public static final String VALUE = "value";

	public static final int VALUE_TIME_TIP = 0;// 7      
	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 List<Message> myList;

	public ChatAdapter(Context context, List<Message> myList) {
		this.myList = myList;

		mInflater = (LayoutInflater) context
				.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
	}

	@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);
		ViewHolderTime holderTime = null;
		ViewHolderRightText holderRightText = null;
		ViewHolderRightImg holderRightImg = null;
		ViewHolderRightAudio holderRightAudio = null;
		ViewHolderLeftText holderLeftText = null;
		ViewHolderLeftImg holderLeftImg = null;
		ViewHolderLeftAudio holderLeftAudio = null;
		
		if (convertView == null) {
			switch (type) {
			case VALUE_TIME_TIP:
				holderTime = new ViewHolderTime();
				convertView = mInflater.inflate(R.layout.list_item_time_tip,
						null);
				holderTime.tvTimeTip = (TextView) convertView
						.findViewById(R.id.tv_time_tip);
				holderTime.tvTimeTip.setText(msg.getValue());
				convertView.setTag(holderTime);
				break;
			//   
			case VALUE_LEFT_TEXT:
				holderLeftText = new ViewHolderLeftText();
				convertView = mInflater.inflate(R.layout.list_item_left_text,
						null);
				holderLeftText.ivLeftIcon = (ImageView) convertView
						.findViewById(R.id.iv_icon);
				holderLeftText.btnLeftText = (Button) convertView
						.findViewById(R.id.btn_left_text);
				holderLeftText.btnLeftText.setText(msg.getValue());
				convertView.setTag(holderLeftText);
				break;

			case VALUE_LEFT_IMAGE:
				holderLeftImg = new ViewHolderLeftImg();
				convertView = mInflater.inflate(R.layout.list_item_left_iamge,
						null);
				holderLeftImg.ivLeftIcon = (ImageView) convertView
						.findViewById(R.id.iv_icon);
				holderLeftImg.ivLeftImage = (ImageView) convertView
						.findViewById(R.id.iv_left_image);
				holderLeftImg.ivLeftImage.setImageResource(R.drawable.test);
				convertView.setTag(holderLeftImg);
				break;

			case VALUE_LEFT_AUDIO:
				holderLeftAudio = new ViewHolderLeftAudio();
				convertView = mInflater.inflate(R.layout.list_item_left_audio,
						null);
				holderLeftAudio.ivLeftIcon = (ImageView) convertView
						.findViewById(R.id.iv_icon);
				holderLeftAudio.btnLeftAudio = (Button) convertView
						.findViewById(R.id.btn_left_audio);
				holderLeftAudio.tvLeftAudioTime = (TextView) convertView
						.findViewById(R.id.tv_left_audio_time);
				holderLeftAudio.tvLeftAudioTime.setText(msg.getValue());
				convertView.setTag(holderLeftAudio);
				break;
			//   
			case VALUE_RIGHT_TEXT:
				holderRightText= new ViewHolderRightText();
				convertView = mInflater.inflate(R.layout.list_item_right_text,
						null);
				holderRightText.ivRightIcon = (ImageView) convertView
						.findViewById(R.id.iv_icon);
				holderRightText.btnRightText = (Button) convertView
						.findViewById(R.id.btn_right_text);
				holderRightText.btnRightText.setText(msg.getValue());
				convertView.setTag(holderRightText);
				break;

			case VALUE_RIGHT_IMAGE:
				holderRightImg= new ViewHolderRightImg();
				convertView = mInflater.inflate(R.layout.list_item_right_iamge,
						null);
				holderRightImg.ivRightIcon = (ImageView) convertView
						.findViewById(R.id.iv_icon);
				holderRightImg.ivRightImage = (ImageView) convertView
						.findViewById(R.id.iv_right_image);
				holderRightImg.ivRightImage.setImageResource(R.drawable.test);
				convertView.setTag(holderRightImg);
				break;

			case VALUE_RIGHT_AUDIO:
				holderRightAudio=new ViewHolderRightAudio();
				convertView = mInflater.inflate(R.layout.list_item_right_audio,
						null);
				holderRightAudio.ivRightIcon = (ImageView) convertView
						.findViewById(R.id.iv_icon);
				holderRightAudio.btnRightAudio = (Button) convertView
						.findViewById(R.id.btn_right_audio);
				holderRightAudio.tvRightAudioTime = (TextView) convertView
						.findViewById(R.id.tv_right_audio_time);
				holderRightAudio.tvRightAudioTime.setText(msg.getValue());
				convertView.setTag(holderRightAudio);
				break;

			default:
				break;
			}
			
		} else {
			Log.d("baseAdapter", "Adapter_:"+(convertView == null) );
			switch (type) {
			case VALUE_TIME_TIP:
				holderTime=(ViewHolderTime)convertView.getTag();
				holderTime.tvTimeTip.setText(msg.getValue());
				break;
			case VALUE_LEFT_TEXT:
				holderLeftText=(ViewHolderLeftText)convertView.getTag();
				holderLeftText.btnLeftText.setText(msg.getValue());
				break;
			case VALUE_LEFT_IMAGE:
				holderLeftImg=(ViewHolderLeftImg)convertView.getTag();
				holderLeftImg.ivLeftImage.setImageResource(R.drawable.test);
				break;
			case VALUE_LEFT_AUDIO:
				holderLeftAudio=(ViewHolderLeftAudio)convertView.getTag();
				holderLeftAudio.tvLeftAudioTime.setText(msg.getValue());
				break;
			case VALUE_RIGHT_TEXT:
				holderRightText=(ViewHolderRightText)convertView.getTag();
				holderRightText.btnRightText.setText(msg.getValue());
				break;
			case VALUE_RIGHT_IMAGE:
				holderRightImg=(ViewHolderRightImg)convertView.getTag();
				holderRightImg.ivRightImage.setImageResource(R.drawable.test);
				break;
			case VALUE_RIGHT_AUDIO:
				holderRightAudio=(ViewHolderRightAudio)convertView.getTag();
				holderRightAudio.tvRightAudioTime.setText(msg.getValue());
				break;

			default:
				break;
			}
			
			//holder = (ViewHolder) convertView.getTag();
		}
		return convertView;
	}

	/**
	 *       position        layout type
	 * 
	 * type     0  
	 * 
	 * */
	@Override
	public int getItemViewType(int position) {

		Message msg = myList.get(position);
		int type = msg.getType();
		Log.e("TYPE:", "" + type);
		return type;
	}

	/**
	 *      layout   
	 * 
	 * */
	@Override
	public int getViewTypeCount() {
		return 7;
	}

	class ViewHolderTime {
		private TextView tvTimeTip;//   
	}

	class ViewHolderRightText {
		private ImageView ivRightIcon;//      
		private Button btnRightText;//      
	}

	class ViewHolderRightImg {
		private ImageView ivRightIcon;//      
		private ImageView ivRightImage;//      
	}

	class ViewHolderRightAudio {
		private ImageView ivRightIcon;//      
		private Button btnRightAudio;//      
		private TextView tvRightAudioTime;//        
	}

	class ViewHolderLeftText {
		private ImageView ivLeftIcon;//      
		private Button btnLeftText;//      
	}

	class ViewHolderLeftImg {
		private ImageView ivLeftIcon;//      
		private ImageView ivLeftImage;//      
	}

	class ViewHolderLeftAudio {
		private ImageView ivLeftIcon;//      
		private Button btnLeftAudio;//      
		private TextView tvLeftAudioTime;//        
	}

}

 
 
2枚の微信、易信の図を共有して、あなたもこのようにすることができます.
ListView具有多种item布局——实现微信对话列       ListView具有多种item布局——实现微信对话列
 
 
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