在Android Listview中以2种不同的布局重用视图

Question

我了解到，要最大程度地提高Android列表视图的效率，您应该只拥有尽可能多的膨胀“行”视图以适合屏幕显示。视图移出屏幕后，应在您的getView方法中重用它，检查是否convertView为null。

但是，当列表需要2种不同的布局时，如何实现此想法？可以说它的订单列表，其中一个布局用于已完成的订单，另一个布局用于在处理中的订单。

这是我的代码正在使用的想法的示例教程。就我而言，我将有2行布局：R.layout.listview_item_product_complete和R.layout.listview_item_product_inprocess

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

ViewHolder holder = null;

if (convertView == null) {
    holder = new ViewHolder();
    if(getItemViewType(position) == COMPLETE_TYPE_INDEX) {
        convertView = mInflator.inflate(R.layout.listview_item_product_complete, null);
        holder.mNameTextView = (TextView) convertView.findViewById(R.list.text_complete);
        holder.mImgImageView = (ImageView) convertView.findViewById(R.list.img_complete);
    }
    else { // must be INPROCESS_TYPE_INDEX
        convertView = mInflator.inflate(R.layout.listview_item_product_inprocess, null);
        holder.mNameTextView = (TextView) convertView.findViewById(R.list.text_inprocess);
        holder.mImgImageView = (ImageView) convertView.findViewById(R.list.img_inprocess);
    }
    convertView.setTag(holder);
} else {
    holder = (ViewHolder) convertView.getTag();
}
    thisOrder = (Order) myOrders.getOrderList().get(position);
    // If using different views for each type, use an if statement to test for type, like above
    holder.mNameTextView.setText(thisOrder.getNameValue());
    holder.mImgImageView.setImageResource(thisOrder.getIconValue());
    return convertView;
}

public static class ViewHolder {
    public TextView mNameTextView;
    public ImageView mImgImageView;
}

Answer 1

您需要让适配器的视图回收器知道不止一种布局，以及如何区分每一行的两种布局。只需覆盖以下方法：

@Override
public int getItemViewType(int position) {
    // Define a way to determine which layout to use, here it's just evens and odds.
    return position % 2;
}

@Override
public int getViewTypeCount() {
    return 2; // Count of different layouts
}

合并getItemViewType()进来getView()，像这样：

if (convertView == null) {
    // You can move this line into your constructor, the inflater service won't change.
    mInflater = (LayoutInflater) mContext.getSystemService(LAYOUT_INFLATER_SERVICE);
    if(getItemViewType(position) == 0)
        convertView = mInflater.inflate(R.layout.listview_item_product_complete, parent, false);
    else
        convertView = mInflater.inflate(R.layout.listview_item_product_inprocess, parent, false);
    // etc, etc...

观看Android的Romain Guy 在Google
Talks上讨论视图回收器。