Question

当日期不同时，我想在ListView中使用分隔符，所以我使用下面的代码尝试这样做。

问题是，在TYPE_SEPARATOR案例的getView（）中，我不能同时展开chatheader和list_right_chat或list_left_chat布局，因为它只是返回最后一个视图。如何在不直接将标题添加到传递给ListView的List中的情况下添加分隔符（标题）和普通布局？

代码：

public class ChatListAdapter extends ArrayAdapter<Message> {
private LayoutInflater mInflater;

public ChatListAdapter(Context context, List<Message> items) {
    super(context, 0, items);
    mInflater = LayoutInflater.from(context);
}

@Override
public int getViewTypeCount() {
    return RowType.values().length;
}

@Override
public int getItemViewType(int position) {
    //Check Dates
    DateTimeZone timeZone = DateTimeZone.getDefault();
    DateTime now = new DateTime( timeZone );
    Interval today = new Interval( now.withTimeAtStartOfDay(), now.plusDays(1).withTimeAtStartOfDay() );
    MutableDateTime epoch = new MutableDateTime();
    epoch.setDate(getItem(position).getEpochTime()); //Set to Epoch time
    DateTime dateTime = new DateTime( epoch );
    boolean messageHappenedToday = today.contains( dateTime );

    if(position == 0)
    {
        if(messageHappenedToday)
            return TYPE_MESSAGE_ITEM;

        return TYPE_SEPARATOR;
    }
    else
    {
        //Check if current message is the same date as the last message.
        //Last message
        epoch.setDate(getItem(position - 1).getEpochTime()); //Set to Epoch time
        DateTime dateTimeLastMessage = new DateTime( epoch );
        Interval oneDayLastMessage = new Interval( dateTimeLastMessage.withTimeAtStartOfDay(), dateTimeLastMessage.plusDays(1).withTimeAtStartOfDay() );

        //Current message
        MutableDateTime epochCurrentMessage = new MutableDateTime();
        epochCurrentMessage.setDate(getItem(position).getEpochTime());
        DateTime dateTimeCurrentMessage = new DateTime(epochCurrentMessage);
        boolean lastMessageHappenedToday = oneDayLastMessage.contains( dateTimeCurrentMessage );

        if(lastMessageHappenedToday)
            return TYPE_MESSAGE_ITEM;
    }
    return TYPE_SEPARATOR;
}

private static final int TYPE_MESSAGE_ITEM = 0;
private static final int TYPE_SEPARATOR = 1;

public View getView(int position, View convertView, ViewGroup parent)  {
    ViewHolder holder = null;
    int rowType = getItemViewType(position);
    View View;
    if (convertView == null) {
        Log.i("Cascade", "4: " + getItem(position).getFromName());

        holder = new ViewHolder();
        switch (rowType) {
            case TYPE_MESSAGE_ITEM:
                if(getItem(position).getSelf())
                    convertView = mInflater.inflate(R.layout.list_right_chat, null);
                else
                    convertView = mInflater.inflate(R.layout.list_left_chat, null);
                holder.View = getItem(position).getView(TYPE_MESSAGE_ITEM, mInflater, convertView);
                break;
            case TYPE_SEPARATOR:
                convertView = mInflater.inflate(R.layout.chatheader, null);
                holder.View = getItem(position).getView(TYPE_SEPARATOR, mInflater, convertView);


                if(getItem(position).getSelf())
                    convertView = mInflater.inflate(R.layout.list_right_chat, null);
                else
                    convertView = mInflater.inflate(R.layout.list_left_chat, null);
                holder.View = getItem(position).getView(TYPE_MESSAGE_ITEM, mInflater, convertView);
                break;
        }
        convertView.setTag(holder);
    }
    else
    {
        holder = (ViewHolder) convertView.getTag();
    }
    return convertView;
}

public static class ViewHolder {
    public  View View; }
}

我总是可以使用View.GONE将标题添加到我的两个布局中，并在需要时将其显示，但这看起来很糟糕＆＃39; ...

Answer 1

我在两个布局中都没有看到任何不好的标题。

特别是，如果在您的情况下，我可以使用RecyclerView和Data Binding一起显示数据，只需几行代码来决定是否显示标题。

Answer 2

您正在将表行添加到表中，因此请使用TableLayout.LayoutParams而不是LinearLayout.LayoutParams。因为我们根据我们要添加的父项使用LayoutParam

            TableLayout table = (TableLayout) findViewById(R.id.TableLayout1);

        TableRow tr = new TableRow(this);
        LinearLayout.LayoutParams trparams = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.WRAP_CONTENT);
        tr.setLayoutParams(trparams);

        cg[i] = new EditText(this);
        weight[i] = new EditText(this);
        cg[i].setInputType(InputType.TYPE_CLASS_NUMBER | InputType.TYPE_NUMBER_FLAG_DECIMAL);
        weight[i].setInputType(InputType.TYPE_CLASS_NUMBER | InputType.TYPE_NUMBER_FLAG_DECIMAL);

        //Here's where it goes wrong. By adding fieldparams, the text field doesn't even get generated.
        LinearLayout.LayoutParams fieldparams = new LinearLayout.LayoutParams(10, LinearLayout.LayoutParams.WRAP_CONTENT, 1.0f);
        tr.addView(cg[i], fieldparams);
        tr.addView(weight[i], fieldparams);

        table.addView(tr);

在ListView

2 个答案: