android - 动态加载数据到 Gridview

Question

当我在 gridview 上工作时，我遇到了以下问题，我们将不胜感激，

1. 当我将数据加载到我的 gridview 时，它只加载数组的前 3 项，但还有 18 项要加载。为什么它不加载其他 15 个项目。 (Log.i 它显示了我的 LogCat 中的所有 18 个项目)。

2. 由于只有 18 个项目属于 MainCategoryID=1，它应该只加载 18 个网格，但是这加载了 28 个网格(这是因为 responseJson 中有 28 个项目)。我想将它限制为 18 个网格。 (加载的28个格子里面，加载了3个item，有几处重复，其他格子都是空格子)

PizzaFragment 类

public class PizzaFragment extends ListFragment implements OnTaskCompleted {

    private TranslateAnimation anim;
    GridView grid;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.menu_grid_main, container, false);

        new PizzaMenuAsyncTask(getActivity(), this).execute();


        grid = (GridView) view.findViewById(R.id.grid);
        return view;
    }

    @Override
    public void onTaskCompleted(JSONArray responseJson) {

        try
        {
            String[] Description = new String[responseJson.length()];
            String[] ImageURL = new String[responseJson.length()];
            for (int i = 0; i < responseJson.length(); i++)
            {
                JSONObject object = responseJson.getJSONObject(i);
                if ((object.getString("MainCategoryID")).equals("1"))
                {
                    Log.i("MainCategoryID ", object.getString("ImageURL"));
                    ImageURL[i] = object.getString("ImageURL");
                    Log.i("MainCategoryID ", object.getString("Description"));
                    Description[i] = object.getString("Description");

                   CustomGrid adapter = new CustomGrid(getActivity(), Description, ImageURL);
                grid.setAdapter(adapter);
                }

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

自定义网格

public class CustomGrid extends BaseAdapter {

    private Context mContext;
    private final String[] Description;
    private final String[] ImageURL;

    public CustomGrid(Context c, String[] Description, String[] ImageURL) {
        mContext = c;
        this.ImageURL = ImageURL;
        this.Description = Description;
    }

    @Override
    public int getCount() {
        return Description.length;
    }

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

    @Override
    public long getItemId(int position) {
        return 0;
    }

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

        LayoutInflater inflater = (LayoutInflater) mContext
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);

        if (convertView == null) {

            grid = new View(mContext);
            grid = inflater.inflate(R.layout.fragment_pizza, null);
            TextView textView = (TextView) grid.findViewById(R.id.grid_text);
            ImageView imageView = (ImageView) grid
                    .findViewById(R.id.grid_image);
            textView.setText(Description[position]);
            Picasso.with(mContext).load(ImageURL[position]).into(imageView);
        } else {
            grid = (View) convertView;
        }

        return grid;
    }
}

这是我的屏幕的样子(这不是真实的图像，但这是它的样子)

Answer 1

一次检查循环onTaskCompleted 方法。您正在创建适配器的实例并在循环内设置为 gridview 我认为在观察和检查您的代码后我发现第一个问题是错误的。

其次，您处理用于填充行的适配器 View 膨胀方法的方式也是错误的，我可以说这不是正确的方式...

因此，检查适配器和 onTaskCompleted 方法的以下代码。

@Override
    public void onTaskCompleted(JSONArray responseJson) {

        try {
            String[] Description = new String[responseJson.length()];
            String[] ImageURL = new String[responseJson.length()];
            JSONArray jArrayCategoryWise = new JSONArray();
            for (int i = 0; i < responseJson.length(); i++) {
                JSONObject object = responseJson.getJSONObject(i);
                if ("1".equalsIgnoreCase(object.getString("MainCategoryID"))) {
                    // add to another jsonarray if MainCategoryID == 1
                    jArrayCategoryWise.put(object);
                }
            }

            /******
             * You can also create class with getter setter method for the
             * Description and ImageUrl.Make the arraylist of the class after
             * parsing jsonArray.
             */
            // which will required on more iteration of your json array response
            CustomGrid adapter = new CustomGrid(getActivity(),
                    jArrayCategoryWise);
            grid.setAdapter(adapter);
        } catch (JSONException e) {
            e.printStackTrace();
        }
    }

一旦检查数据是否正常传输。或者您是否在两者之间添加任何内容

适配器

    public class CustomGrid extends BaseAdapter {

    private Context context;
    private Context mContext;
    // private final String[] Description;
    // private final String[] ImageURL;
    private JSONArray json;
    private int size = 0;

    public CustomGrid(Context c, JSONArray json) {
        this.context = c;
        this.json = json;
        if (this.json != null)
            size = this.json.length();
        // You can also create class with getter setter method (getter setter
        // for Descriptions and ImageUrl). and pass arraylist of that class

        // this.Description = Description;
        // this.ImageURL = ImageURL;
    }

    @Override
    public int getCount() {
        return size;
    }

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

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder holder;
        if (convertView == null) {
            holder = new ViewHolder();
            convertView = LayoutInflater.from(context).inflate(
                    R.layout.custom_trips_frag_row, parent, false);
            holder.ivImage = (ImageView) convertView
                    .findViewById(R.id.grid_image);
            holder.tvHeader = (TextView) convertView
                    .findViewById(R.id.grid_text);
            convertView.setTag(holder);

        } else {
            holder = (ViewHolder) convertView.getTag();
        }
        JSONObject jObjectRowData = this.json.getJSONObject(position);
        holder.tvHeader.setText(jObjectRowData.getString("Description"));
        Picasso.with(this.context).load(jObjectRowData.getString("ImageURL"))
                .into(holder.ivImage);

        return convertView;
    }

    private class ViewHolder {
        private TextView tvHeader;
        private ImageView ivImage;
    }
}

请检查答案.. 希望我能正确回答你的问题，你也能得到你的答案... * 建议 * 一旦检查 ViewHolder BaseAdapter 的类模式。