Question

在此代码中，在将新项目添加到adapert后，我的列表无法刷新并使用notifyDataSetChanged()进行更新，例如对于此行，我的适配器可以设置没有任何问题。

adapter = new ReceivedAdapter(context, items);
getRequestFromServer(0, 10);

之后我在列表和适配器中有10个项目。

private String getRequestFromServer(long lastID, int count) {
    String received = "";
    try {
        received = new JsonService(config_username, config_password, lastID, count, G.F_RECEIVE_SMS).request();
        JSONArray data_array = new JSONArray(received);

        String mUserID = config_username;
        for (int i = 0; i < data_array.length(); i++) {
            JSONObject json_obj = data_array.getJSONObject(i);

            String mLastID = json_obj.getString("id_recived_sms");
            String mSmsBody = json_obj.getString("sms_body");
            String mSmsNumber = json_obj.getString("sms_number");
            String mSenderName = json_obj.getString("mobile_number");
            String mContactName = json_obj.getString("contact_name");
            String mDate = json_obj.getString("recived_date");

            ReceivedItemStructure item = new ReceivedItemStructure(
                    mLastID,
                    mUserID,
                    mSmsBody,
                    mSmsNumber,
                    mSenderName,
                    mContactName,
                    mDate
            );
            items.add(item);
        }
        setListAdapter(adapter);
    } catch (Exception e) {
        e.printStackTrace();
    }
    return received;
}

items.add(item);计数是10。现在在这个bewlo函数中从服务器获取新的i项后我的列表计数可以更改并更新为11

private void addDataToList(String LastID, String SmsBody, String SmsNumber, String SenderName, String ContactName, String Date) {
    String mLastID      = LastID;
    String mUserID      = config_username;
    String mSmsBody     = SmsBody;
    String mSmsNumber   = SmsNumber;
    String mSenderName  = SenderName;
    String mContactName = ContactName;
    String mDate = Date;
    ReceivedItemStructure item = new ReceivedItemStructure(
            mLastID,
            mUserID,
            mSmsBody,
            mSmsNumber,
            mSenderName,
            mContactName,
            mDate
    );
    items.add(item);
    adapter.setRow(items);
    adapter.notifyDataSetChanged();
}

items.add(item);计数是11。我是adapter.setRow()的更新适配器，ReceivedAdapter我的List尺寸是11。使用addDataToList()函数后我的列表是11但adapter.notifyDataSetChanged();不起作用，我在适配器和列表视图中看不到新项。使用通过List的新项目添加和更新items的所有方式都可以，并且ReceivedAdapter并且我没有问题。

我的适配器是：

public class ReceivedAdapter extends BaseAdapter
{
    private LayoutInflater inflater;
    private List<ReceivedItemStructure> row;
    public ReceivedAdapter(Context context, List<ReceivedItemStructure> row)
    {
        this.row = row;
        inflater = LayoutInflater.from(context);
    }
    public void setRow(List<ReceivedItemStructure> row) {
        this.row = row;
    }
    @Override
    public int getCount() {
        return row.size();
    }
    @Override
    public ReceivedItemStructure getItem(int position) {
        return row.get(position);
    }
    @Override
    public long getItemId(int position) {
        return 0;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent)
    {
        if(convertView ==null){
            convertView = inflater.inflate(R.layout.received_sms_list_fragment, null);
        }
        TextView tv_smsBody = (TextView)convertView.findViewById(R.id.tv_smsBody);
        tv_smsBody.setText(getItem(position).getmSmsBody());

        TextView tv_smsSender = (TextView)convertView.findViewById(R.id.tv_smsSender);
        tv_smsSender.setText(getItem(position).getmSmsBody());

        TextView tv_smsDate = (TextView)convertView.findViewById(R.id.tv_smsDate);
        tv_smsDate.setText(getItem(position).getmDate());
        return convertView;
    }
}

Answer 1

不是每次都创建一个新的items并将其设置为适配器..尝试直接从适配器添加和删除。

首先使用您需要的初始值或空list初始化适配器。

接下来要添加..来电adapter.add(obj)
如果您要删除来电adapter.remove(obj)
如果要清空适配器呼叫adapter.clear()

最后，只要您需要反映更改，请致电adapter.notifyDatasetChanged()

Answer 2

请尝试这种方式，希望这有助于您解决问题。

public class ReceivedAdapter extends BaseAdapter
{
    private Context context;
    private List<ReceivedItemStructure> row;
    public ReceivedAdapter(Context context, List<ReceivedItemStructure> row)
    {
        this.context = context;
        this.row = row;
    }
    public void addItem(ReceivedItemStructure item) {
        if(row!=null){
            row.add(item);
            notifyDataSetChanged();
        }
    }
    public void removeItem(ReceivedItemStructure item) {
        if(row!=null){
            row.remove(item);
            notifyDataSetChanged();
        }
    }
    public void removeItemAtPosition(int position) {
        if(row!=null){
            row.remove(position);
            notifyDataSetChanged();
        }
    }
    public void clearAll() {
        if(row!=null){
            row.clear();
            notifyDataSetChanged();
        }
    }
    @Override
    public int getCount() {
        return row.size();
    }
    @Override
    public ReceivedItemStructure getItem(int position) {
        return row.get(position);
    }
    @Override
    public long getItemId(int position) {
        return 0;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent)
    {
        ViewHolder holder;
        if(convertView ==null){
            holder = new ViewHolder();
            convertView = LayoutInflater.from(context).inflate(R.layout.received_sms_list_fragment, null);
            holder.tv_smsBody = (TextView)convertView.findViewById(R.id.tv_smsBody);
            holder.tv_smsSender = (TextView)convertView.findViewById(R.id.tv_smsSender);
            holder.tv_smsDate = (TextView)convertView.findViewById(R.id.tv_smsDate);
            convertView.setTag(holder);
        }else{
            holder = (ViewHolder) convertView.getTag();
        }
        holder.tv_smsBody.setText(getItem(position).getmSmsBody());
        holder.tv_smsSender.setText(getItem(position).getmSmsBody());
        holder.tv_smsDate.setText(getItem(position).getmDate());
        return convertView;
    }

    class ViewHolder{
        TextView tv_smsBody;
        TextView tv_smsSender;
        TextView tv_smsDate;
    }
}

使用BaseAdapter的Android刷新适配器

2 个答案: