android - 如何从android中的 Activity 中选择自定义 ListView 中的所有复选框

Question

我有一个自定义 ListView ，其中包含两个 TextView 和一个复选框。选中复选框时，id 将存储在数据库中，如果未选中，则 id 将从数据库中删除。但我想选择所有复选框并将所有 ID 存储到数据库中，或者取消选中所有复选框并从数据库中删除所有 ID。我必须为此实现什么。请帮助我这是我的适配器代码

public class InviteListAdapter2 extends BaseAdapter implements OnClickListener {

private static final String TAG = "GroupEditMemberListAdapter";

private LayoutInflater inflater;
private ViewHolder holder;
private List<FriendItem> list;
private Context context;
private ImageLoader imageLoader;
MessageSendingActivity msg = new MessageSendingActivity();
private String groupId;
SqliteHandle sqhandle;
//private String adminId;
int total_contacts=0;
String f_id;
int flag=0;
String chetimeslot;
ArrayList<String> currentList = new ArrayList<String>();
public static final String DELETE_MEMBER = "2";
public static final String ADD_MEMBER = "1";

public InviteListAdapter2(Context context, List<FriendItem> list, String groupId, String adminId) {
    this.context = context;
    inflater = LayoutInflater.from(context);
    this.list = list;
    imageLoader = new ImageLoader(context);
    this.groupId = groupId;
    //this.adminId = adminId;
}   

public ArrayList<String> getChekedItem()
{
    if(currentList!=null)
    return this.currentList;
    else return null;
}
@Override
public int getCount() {
    return list.size();
}

@Override
public Object getItem(int position) {
    return list.get(position);
}

@Override
public long getItemId(int position) {
    return list.indexOf(getItem(position));
}

public void refresh(List<FriendItem> list) {
    this.list = list;
    notifyDataSetChanged();
}

public List<FriendItem> getList() {
    return list;
}

View hView;

ArrayList<CheckedItem> checkbox_timeslot = new ArrayList<CheckedItem>();
@Override
public View getView(final int position, View convertView, ViewGroup parent) {

    hView = convertView;

    final FriendItem item = list.get(position);

    if (convertView == null) {

        holder = new ViewHolder();

        hView = inflater.inflate(R.layout.friendlistitem, null);
        holder.nameTextView         = (TextView) hView.findViewById(R.id.friend_name_text);
        holder.statusTextView       = (TextView) hView.findViewById(R.id.friend_count_text);
        holder.userImageView        = (ImageView) hView.findViewById(R.id.friend_image);
        holder.checkBox             = (CheckBox) hView.findViewById(R.id.chekbox);

        hView.setTag(holder);
    }
    else {
        holder = (ViewHolder) hView.getTag();
    }

    try {
            holder.nameTextView.setText(""+item.getName() + " " +item.getLname());
            holder.statusTextView.setText(""+item.getContacts());

            String path = "http://www.gbggoa.org/testproject/four/images/pic.jpg";
            path = Constant.URL  + item.getImage();
            imageLoader.displayImage(path, holder.userImageView);

            if(item.getId().equals(Sessions.getUserId(context)))
            {
                holder.checkBox.setVisibility(View.GONE);
            }
            else
            {
                holder.checkBox.setVisibility(View.VISIBLE);
            }

            if(item.isChecked())
            {
                holder.checkBox.setChecked(true);

                if(item.getId().equals(Sessions.getUserId(context)))
                {
                    hView.setBackgroundResource(R.drawable.selector_list_gray);
                }
                else
                {
                    hView.setBackgroundResource(R.drawable.selector_list_green);
                }
            }
            else
            {
                holder.checkBox.setChecked(false);
                hView.setBackgroundResource(R.drawable.selector_list);
            }   

            holder.checkBox.setTag(position);
            holder.checkBox.setOnClickListener(this);

    } catch (Exception e) {
        e.printStackTrace();
    }

    return hView;
}   

class ViewHolder
{   
    TextView nameTextView, statusTextView;
    ImageView userImageView;
    CheckBox checkBox;
}

protected void showToast(String message) {
    Toast.makeText(context, ""+message, Toast.LENGTH_SHORT).show();
}

protected void showToastLong(String message) {
    Toast.makeText(context, ""+message, Toast.LENGTH_LONG).show();
}   

@Override
public void onClick(View view) {

    final int position = (Integer) view.getTag();
    String f_id=list.get(position).getId();
    final CheckBox checkBox = (CheckBox) view.findViewById(R.id.chekbox);
    sqhandle=new SqliteHandle(context); 
    final boolean isChecked = checkBox.isChecked();
    int total=sqhandle.getCheckedCount();                       
    checkBox.setVisibility(View.GONE);
    if(isChecked)
    {
        total_contacts = total_contacts + Integer.parseInt(list.get(position).getContacts());
        sqhandle.changeCheck("1", f_id);
        Toast.makeText(context, "Selected Contacts: "+total_contacts, Toast.LENGTH_LONG).show();

    }
    else
    {
        sqhandle.changeCheck("0", f_id);
        total_contacts = total_contacts - Integer.parseInt(list.get(position).getContacts());
        Toast.makeText(context, "Selected Contacts: "+total_contacts, Toast.LENGTH_LONG).show();
    }
    sqhandle.close();
    checkBox.setVisibility(View.VISIBLE);
    list.get(position).setChecked(isChecked);
    notifyDataSetChanged();

}


}   

Answer 1

尝试以下操作:

1. 在 Activity 布局中的 ListView 顶部添加一个复选框。例如，id 为 chkall 的复选框。

2. 使用 getter 和 setter 在您的适配器类 InviteListAdapter2 中添加一个名为 checkedAll 的 bool 标志。

3. 创建添加/删除数据库如下:

   public void modifyFriends(List<FriendItem> fList, boolean checkedAll){
       String checkStatus = "0";   
       if(checkedAll){
           checkStatus = "1";
       }
       //sql code to change check status in database for all friends
   }
   

4. 将 getView() 您的适配器代码稍微更改如下:

   if(item.isChecked() || checkedAll)
       {
           holder.checkBox.setChecked(true);
   
           if(item.getId().equals(Sessions.getUserId(context)))
           {
               hView.setBackgroundResource(R.drawable.selector_list_gray);
           }
           else
           {
               hView.setBackgroundResource(R.drawable.selector_list_green);
           }
       }
       else
       {
           holder.checkBox.setChecked(false);
           hView.setBackgroundResource(R.drawable.selector_list);
       }
   

5. 点击 chkall 复选框，执行以下操作:

       if(checked){
           inviteListAdapter2.setCheckedAll(true);
           modifyFriends(friendsList, true); //call a db helper method to change reflect check status in db
       }else{
           inviteListAdapter2.setCheckedAll(false);
           modifyFriends(friendsList, false); //call a db helper method to change reflect check status in db
       }
       inviteListAdapter2.notifyDatasetChaged();