java - 无法使用自定义适配器设置第一个 ListView 项目

Question

我使用自定义适配器、消息类等...我无法更新第一个 ListItem，第二个和其他列表项已正确添加到我的 Listview 中。我所说的更新是指默认情况下我拥有 textView 文本的名称，而不是消息!

你能帮我理解为什么吗？谢谢你!这是代码的一部分:(listView位于对话框窗口中)

 // (variables put in public static)
 chat_dialogue = new Dialog(context, R.style.hidetitle);                    
 chat_dialogue.getWindow().setType(WindowManager.LayoutParams.TYPE_SYSTEM_ALERT);
 chat_dialogue.setContentView(R.layout.wakeupcalls); // show the dialogue                   
 edit_Text_Chat = (EditText) chat_dialogue.findViewById(R.id.editText_chat);                
 chat_listView = (ListView)chat_dialogue.findViewById(R.id.ListViewChat);

 Fsa.messages = new ArrayList<Message>();

 Fsa.messages.add(new Message(the_sender,the_message,"(" + Fsa.date + Fsa.pre_mess2 + Fsa.heure + ")",true));

 adapter = new bubbleadapter(context,messages);

 chat_listView.setAdapter(adapter);                 
 adapter.notifyDataSetChanged();    
 chat_listView.setSelection(messages.size()-1);

然后我添加了一些来自其他方法的新消息，它们显示得很好，但不是上面的这个! (正如我所说，这只是第一个!)

现在是自定义适配器:

public class bubbleadapter extends BaseAdapter{
private Context mContext;
private ArrayList<Message> mMessages;


public bubbleadapter(Context context, ArrayList<Message> messages){
    super();        
    this.mContext = context;
    this.mMessages = messages;

}
@Override
public int getCount(){      
    return mMessages.size();

}
@Override
public Object getItem(int position) {

    return mMessages.get(position);
}

public View getView(int position, View convertView, ViewGroup parent) {
     Message message = (Message) this.getItem(position);


    ViewHolder holder;
    if (convertView ==null) {           
        holder = new ViewHolder();
        convertView = LayoutInflater.from(mContext).inflate(R.layout.chat_row, parent,false);
        holder.sender = (TextView) convertView.findViewById(R.id.textVSender);
        holder.message = (TextView) convertView.findViewById(R.id.message_text1);
        holder.date = (TextView) convertView.findViewById(R.id.textVDate);
        convertView.setTag(holder);
    } else {


        holder = (ViewHolder) convertView.getTag();
        holder.sender.setText(message.getSender());
        holder.message.setText(message.getMessage());
        holder.date.setText(message.getDate());

        LayoutParams lp = (LayoutParams) holder.message.getLayoutParams();

        if (message.isStatusMessage()) {

            holder.message.setBackgroundDrawable(null);
            holder.sender.setText(message.getSender());         
                holder.sender.setTextColor(Color.parseColor("#405478"));

        } else {

            if (message.isMine()) {                 
                holder.message.setBackgroundResource(R.drawable.speech_bubble_green);                   
                lp.gravity = Gravity.RIGHT;
            } else {                    
                holder.message.setBackgroundResource(R.drawable.speech_bubble_orange);
                lp.gravity = Gravity.LEFT;
            }
            holder.message.setLayoutParams(lp);             
        }           
    }

    return convertView;
}

private static class ViewHolder {
     TextView sender;
     TextView message;
     TextView date;
}

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

 }

Answer 1

删除else语句如下:

public View getView(int position, View convertView, ViewGroup parent) {
     Message message = (Message) this.getItem(position);


ViewHolder holder;
if (convertView ==null) {           
    holder = new ViewHolder();
    convertView = LayoutInflater.from(mContext).inflate(R.layout.chat_row, parent,false);
    holder.sender = (TextView) convertView.findViewById(R.id.textVSender);
    holder.message = (TextView) convertView.findViewById(R.id.message_text1);
    holder.date = (TextView) convertView.findViewById(R.id.textVDate);
    convertView.setTag(holder);
} 


    holder = (ViewHolder) convertView.getTag();
    holder.sender.setText(message.getSender());
    holder.message.setText(message.getMessage());
    holder.date.setText(message.getDate());

    LayoutParams lp = (LayoutParams) holder.message.getLayoutParams();

    if (message.isStatusMessage()) {

        holder.message.setBackgroundDrawable(null);
        holder.sender.setText(message.getSender());         
            holder.sender.setTextColor(Color.parseColor("#405478"));

    } else {

        if (message.isMine()) {                 
            holder.message.setBackgroundResource(R.drawable.speech_bubble_green);                   
            lp.gravity = Gravity.RIGHT;
        } else {                    
            holder.message.setBackgroundResource(R.drawable.speech_bubble_orange);
            lp.gravity = Gravity.LEFT;
        }
        holder.message.setLayoutParams(lp);             
    }           


return convertView;
}