ListView Viewholder复选框状态

Question

I've some problems with my ListView custom adapter (and its newly implemented viewHolder). I have a ListView with a checkbox for each item (nothing new here). The problem is, if there is more than 9 items in my list, when I check the first checkbox, the tenth will be automatically checked (same for the second with the eleventh) just like if there were one listener for both item (and I beleive it's the case in some way).

I read about the position issue with listView, view recycling and the ViewHolder way to solve it here: How can I make my ArrayAdapter follow the ViewHolder pattern?

But I probably made something wrong because it's not working...

public class PresenceListAdapter extends SimpleAdapter {
private LayoutInflater  inflater;
private List<Integer> ids;
private List<String> statuts;

public PresenceListAdapter (Context context, List<? extends Map<String, ?>> data, int resource, String[] from, int[] to, List<Integer> ids, List<String> statuts)
{
    super (context, data, resource, from, to);
    inflater = LayoutInflater.from (context);
    this.ids = ids;
    this.statuts= statuts;

}

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

@Override
public View getView (int position, View convertView, ViewGroup parent)
{

    ViewHolder holder;

    if (convertView == null)
    {
        convertView = inflater.inflate (R.layout.list_text_checkbox, null);

        holder = new ViewHolder();

        holder.btn = (Button) convertView.findViewById(R.id.btnRetard);
        holder.check = (CheckBox) convertView.findViewById(R.id.checkPresent);

        if (statuts.get(position).equals("P")) {
            Drawable img = inflater.getContext().getResources().getDrawable(android.R.drawable.presence_online);
            holder.btn.setCompoundDrawablesWithIntrinsicBounds( img, null, null, null );
            holder.btn.setEnabled(true);
            holder.check.setChecked(true);
        }
        else if(statuts.get(position).equals("R"))
        {
            Drawable img = inflater.getContext().getResources().getDrawable(android.R.drawable.presence_away);
            holder.btn.setCompoundDrawablesWithIntrinsicBounds( img, null, null, null );
            holder.btn.setEnabled(true);
            holder.check.setChecked(true);
        }
        else 
        {
            Drawable img = inflater.getContext().getResources().getDrawable(android.R.drawable.presence_invisible);
            holder.btn.setCompoundDrawablesWithIntrinsicBounds( img, null, null, null );
            holder.check.setChecked(false);
        }

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

    int id = ids.get(position);

    if(id != 0)
    {
        holder.check.setTag(id);
        holder.btn.setTag(id);
    }

    return super.getView (position, convertView, parent);
}

static class ViewHolder {
    Button btn;
    CheckBox check;
}

And my listener: public void changerPresent(View v) {

    CheckBox checkPresent = (CheckBox) v;
    int idPersonne = (Integer) checkPresent.getTag();
    View parent = (View)v.getParent();
    Button btn = (Button) parent.findViewById(R.id.btnRetard);

    if(checkPresent.isChecked()) {
        gestion.updatePresence(idPersonne, idSeance, "P");

        btn.setEnabled(true);
        setBtnRetardPresent(btn);           
    }
    else 
    {
        gestion.updatePresence(idPersonne, idSeance, "A");
        btn.setEnabled(false);
        setBtnRetardAbsent(btn);

    }

}

I would appreciate any help at this point, I'm working on this for hours now.

Thank you very much.

Answer 1

Here's how I made it work:

First, you need a separate array for your checked state. It has to be the same size as your adapter's getCount() .

Then on your getView, your checkbox's setOnCheckedChangedListener MUST PRECEED your checkbox.setChecked statements.

example:

holder.checkBox.setOnCheckedChangeListener(new OnCheckedChangeListener() {
  @Override
  public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
    isChecked[position] = isChecked;
  }
});

holder.checkBox.setChecked(isChecked[position]);

Answer 2

The problem is because of the fact that listview recycles it views

so in getView( ) method

     if (convertView == null)
        {
    ........
         }
    else 
        {
            holder = (ViewHolder) convertView.getTag();


        }
  // Uncheck needed boxes here... You need to implement your logic 
        if( 'position' is checked earlier)
         holder.check.setChecked(true);
        else
        holder.check.setChecked(false);

You need to write the code to manage the state of view if the convert is not null, because it is a already used view which may be having checked check boxes.

Answer 3

You should set CheckedBox state outside the initialization of ViewHolder, like the following code:

if (convertView == null) {
    viewHolder = new ViewHolder();
    convertView.setTag(viewHolder);
} else {
    viewHolder = (ViewHolder) convertView.getTag();
}

viewHolder.checkedBox.setChecked();

BTW: use SparseBooleanArray instead of two list to store CheckedBox state.