java - 使用自定义 ListView 时的奇怪行为

Question

我的适配器及其 SetAdd 类表现得很奇怪。

我的 gridview 包含带有 imageview 的项目以及其上方的通知文本。

gridview 使用自定义 ArrayList 进行填充。

这是执行此操作的代码:

Items = new ArrayList<SetAdd>();
SetAdd item0 = new SetAdd();
item.setNewNews(5);
item0.setImageID(images[1]);
Items.add(item0);

SetAdd item1 = new SetAdd();
item.setNewNews(3);
item1.setImageID(images[2]);
Items.add(item1);

SetAdd item2 = new SetAdd();
item.setNewNews(4);
item2.setImageID(images[3]);
Items.add(item2);

NewsGV = (GridView) findViewById(R.id.gridView_NEWS);
        NewsAdapter adapter = new NewsAdapter(this, Items);
        NewsGV.setAdapter(adapter);

这是我的 SetAdd 类:

public class SetAdd {

public int getImageId() {
    return imageId;
}

public void setImageID(int imageId) {
    this.imageId = imageId;
}

public int getNewNews() {
    return newNews;
}

public void setNewNews(int newNews) {
    this.newNews = newNews;
    Log.d("setNewNews in SetAdd: ", String.valueOf(newNews));
}

private int imageId;
private int newNews;
}

这是我的适配器类:

公共(public)类 NewsAdapter 扩展了 ArrayAdapter {

private static List<SetAdd> News;
private Activity context;
private LayoutInflater l_inflater;

public NewsAdapter(Activity context, List<SetAdd> News) {
    super(context, R.layout.news_grid_view_template, News);
    this.context = context;
    this.News = News;

}

private class ViewHolder {
    ImageView img;
    ImageView imgCircle;
    TextView txtNewNews;
}

public SetAdd getItem(int position) {
    return News.get(position);
}

public View getView(int position, View convertView, ViewGroup parent) {
    ViewHolder holder;
    LayoutInflater inflater = context.getLayoutInflater();

    if (convertView == null) {
        convertView = inflater.inflate(R.layout.news_grid_view_template,
                null);
        holder = new ViewHolder();
        holder.txtNewNews = (TextView) convertView
                .findViewById(R.id.txtNewNews);
        holder.img = (ImageView) convertView
                .findViewById(R.id.img_ImagePlaceHolder);
        holder.imgCircle = (ImageView) convertView
                .findViewById(R.id.imgCircle);
        convertView.setTag(holder);
    } else {
        holder = (ViewHolder) convertView.getTag();
    }

    SetAdd items = (SetAdd) getItem(position);

    Log.d("Got New News number is: ", String.valueOf(items.getNewNews()));
    //Log.d("Got new Image Id is: ", String.valueOf(items.getImageId()));
    if (items.getNewNews() == 0) {
        holder.txtNewNews.setVisibility(View.GONE);
        holder.imgCircle.setVisibility(View.GONE);
    } else {
        holder.txtNewNews.setText(String.valueOf(items.getNewNews()));
    }
    holder.img.setImageResource(items.getImageId());

    return convertView;
}
}

现在的问题是: 我的列表 gridview 填充了适当的图像，但有 0 个新新闻。 我以相同的方式设置 imageID 和 NewNews 但 item.setNewNews() 给出 0 结果，无论我输入什么值。

Answer 1

您的代码中有错误(可能是输入错误)。您永远不会设置 item1 和 item2

的值

Items = new ArrayList<SetAdd>();
SetAdd item0 = new SetAdd();
item0.setNewNews(5);
item0.setImageID(images[1]);
Items.add(item0);

SetAdd item1 = new SetAdd();
item1.setNewNews(3); // changed this line
item1.setImageID(images[2]);
Items.add(item1);

SetAdd item2 = new SetAdd();
item2.setNewNews(4); // changed this line
item2.setImageID(images[3]);
Items.add(item2);