带有两个按钮的 Android ListView 设置可见性问题

Question

我有Drag Sort Listview包含以下项目。

1) TextView
2)两个按钮(ON和OFF，一次只有一个按钮可见)

Image with OFF state .
Image with ON state .

我的问题是，当用户点击 ON 并滚动 ListView 并返回到该项目时，它不会更改为 ON。

我试过了:

public class Item {

    public String title;  
    boolean selected = false;

}
public void setSelected(boolean selected) {
    this.selected = selected;
}

在 getView() 方法内部:

 public View getView(final int position, View convertView,
            ViewGroup parent) {
        View v = super.getView(position, convertView, parent);
        if (v != convertView && v != null) {
            ViewHolder holder = new ViewHolder();
            TextView tv = (TextView) v.findViewById(R.id.txtsettingname);
            ImageButton btnoff = (ImageButton) v.findViewById(R.id.btnoff);
            ImageButton btnon = (ImageButton) v.findViewById(R.id.btnon);
            holder.title = tv;
            holder.btnoff = btnoff;
            holder.btnon = btnon;
            v.setTag(holder);
        }
        final ViewHolder holder = (ViewHolder) v.getTag();
        String albums = getItem(position).title;
        holder.btnoff.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                try {
                    ImageButton cb = (ImageButton) v;
                    Item _state = (Item) cb.getTag();
                    _state.setSelected(false);
                    holder.btnon.setVisibility(View.VISIBLE);
                    holder.btnoff.setVisibility(View.GONE);


            } catch (Exception e) {
                // TODO: handle exception
                e.printStackTrace();
            }
        }
    });
    holder.btnon.setOnClickListener(new OnClickListener() {
        @Override
        public void onClick(View v) {
            try {
                ImageButton cb = (ImageButton) v;
                Item _state = (Item) cb.getTag();
                _state.setSelected(true);

                // TODO Auto-generated method stub
                holder.btnoff.setVisibility(View.VISIBLE);
                holder.btnon.setVisibility(View.GONE);



            } catch (Exception e) {
                // TODO: handle exception
                e.printStackTrace();
            }
        }
    });

    holder.title.setText(albums);
    Item state = myarrraylist.get(position);

    if (state.isSelected()) {
        holder.btnon.setVisibility(View.VISIBLE);
        holder.btnoff.setVisibility(View.GONE);
    } else {
        holder.btnon.setVisibility(View.GONE);
        holder.btnoff.setVisibility(View.VISIBLE);
    }
    holder.btnon.setTag(state);

    return v;
}

请帮忙。

Answer 1

简单地说，您需要保持 ON 或 OFF 的选定状态，只需保存 Button 的位置并获取它并保存状态即可了解更多详细信息，您可以查看 how recycling of ListView works .另外，对于工作演示示例，您可以查看我的博客 Rat-a-tat-a-tat Ratatouille已在此答案中指出。

我只为 btnoff 按钮显示，你也可以为其他按钮显示

Psuedo code 在你的代码中会是这样的，

public View getView(final int position, View convertView,
            ViewGroup parent) {
           ViewHolder holder;
        if (convertView == null) {
            holder = new ViewHolder();
            holder.title tv = (TextView) convertView.findViewById(R.id.txtsettingname);
            holder.btnoff btnoff = (ImageButton) convertView.findViewById(R.id.btnoff);
            holder.btnon btnon = (ImageButton) convertView.findViewById(R.id.btnon);

        holder.btnoff.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
            int pos = (Integer)v.getTag();
        myarrraylist.get(pos).setSelected(false);
        }
    });

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

        holder.btnoff btnoff.setTag(position);
        holder.btnoff btnon.setTag(position);


    if (myarrraylist.get(position).isSelected()) {
        holder.btnon.setVisibility(View.VISIBLE);
        holder.btnoff.setVisibility(View.GONE);
    } else {
        holder.btnon.setVisibility(View.GONE);
        holder.btnoff.setVisibility(View.VISIBLE);
    }