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问题：我试图使用自定义ListView在聊天中显示消息。我用我自己班的对象参数化了ArrayList，代码如下。android自定义ListView - 试图了解getView（）如何工作
问题：消息文本和时间戳总是保持不变，每次布局膨胀时，getView()方法中的某些错误，但我无法弄清楚什么。
P.S. ChatActivity包含很多代码，我只会发布与问题相关的事情以保持清洁。
Message.java：
public class Message{
/*
* 1- outgoing
* 2-incoming
* */
public String message;
public String timestamp;
public TextView tvmessage, tvtimestamp;
public ImageView indicator;
public int type;
public Message(String text, int type){
this.timestamp = generateTimestamp();
this.message = text;
this.type=type;
Log.d("Message", message);
//Message text is set correctly each time the constructor is called
}
@SuppressLint("SimpleDateFormat")
public String generateTimestamp() {
SimpleDateFormat sdf = new SimpleDateFormat("HH:mm");
String ts = sdf.format(new Date());
return ts;
}
}
ChatActivity：
private ArrayList<Message> OutgoingMessagesList;
private SingleChatAdapter adapter;
private EditText etInput;
lv = getListView();
adapter = new SingleChatAdapter(this, OutgoingMessagesList);
lv.setAdapter(adapter);
public void sendMessage() {
String tmpMessage = etInput.getText().toString().trim();
/*--- check whether the message string is empty ---*/
if (tmpMessage.length() > 0) {
Message msg = new Message(tmpMessage, 1);
OutgoingMessagesList.add(msg);
/*
* TODO: save the message to local database, send the message to
* server, save it to server database and forward to the recipient
*/
adapter.notifyDataSetChanged();
etInput.setText("");
} else {
MiscUtils.gibShortToast(this, getString(R.string.msgEmpty));
}
}
适配器类，我认为这个问题是：从我的Message类
public final class SingleChatAdapter extends BaseAdapter {
private Context context;
Message msg;
private ArrayList<Message> messages;
public SingleChatAdapter(Context context, ArrayList<Message> chat) {
this.context = context;
this.messages = chat;
Log.d("ChatAdapter", "called constructor");
}
public int getCount() {
return messages.size();
}
public Object getItem(int position) {
return messages.get(position);
}
public long getItemId(int position) {
return position;
}
public View getView(int position, View convertView, ViewGroup viewGroup) {
msg = (Message) getItem(position);
if (convertView == null) {
LayoutInflater inflater = (LayoutInflater) context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
// TODO message_incoming should be inflated for messages received
// from server
convertView = (LinearLayout) inflater.inflate(
R.layout.message_outgoing, null);
convertView.setTag(msg);
} else {
msg = (Message) convertView.getTag();
}
msg.tvmessage = (TextView) convertView
.findViewById(R.id.tvMessageOutgoing);
msg.tvtimestamp = (TextView) convertView.findViewById(R.id.tvTimestamp);
msg.indicator = (ImageView) convertView
.findViewById(R.id.imgMessageState);
msg.tvmessage.setText(msg.message);
msg.tvtimestamp.setText(msg.timestamp);
return convertView;
}
消息字符串包含正确的每次都会有一个值，但是充值到列表中的文本总是保持不变。我错过了什么？如果你想了解的ListView作品和getView如何引用this聊罗马盖伊也是一个不错的博客文章
你有没有尝试删除else语句（内getView一）中提到？ –