Question

我正在动态创建一个弹出菜单，其中的项目将从Web服务中填充。

情况是，解析已经在MainActivity.java，但弹出菜单在BaseAdapter.java类内。我在MainActivity.java内的数组中添加了所有菜单项。请参考下面的代码：

try {
        JSONArray jsonArray = new JSONArray(menuItemsResponse.toString());
        for (int i = 0; i < jsonArray.length(); i++){
        JSONObject object = jsonArray.getJSONObject(i);
        String strMenuItemNames = object.getString("Name");

        listMenuItems.add(strMenuItemNames);
                }

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

我正在使用List<String> listMenuItems在listMenuItems.add(strMenuItemNames)内添加项目。

现在，我想从BaseAdapter类中访问此listMenuitems。下面是我在BaseAdapter类中的getView()方法中的弹出菜单代码：

PopupMenu popupMenu = new PopupMenu(activity, imgDropDown);
popupMenu.getMenu().add()  // array to be added here


popupMenu.setOnMenuItemClickListener(new PopupMenu.OnMenuItemClickListener({
   // on click events for each item
});

任何有解决方案的人都请回复。

提前致谢！

Answer 1

1.添加您需要在构造方法中使用的列表信息。

List<String> listMenuItems;
public MyAdapter(List<String> listMenuItems, Context context) {
   ...
}

2.在您的代码中使用它。

popupMenu.getMenu().add(listMenuItems.get(position));

试试这个。

public class MyAdapter extends BaseAdapter {

    List<String> listMenuItems;
    private LayoutInflater inflater;
    private Context context;

    public MyAdapter(List<String> listMenuItems, Context context) {
        this.context = context;
        this.listMenuItems = listMenuItems;
        this.inflater = LayoutInflater.from(context);
    }

    ...

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        View view = inflater.inflate(R.layout.your_layout, null);
        ...

        PopupMenu popupMenu = new PopupMenu(activity, imgDropDown);
        // edited here 
        popupMenu.getMenu().add(listMenuItems.get(position));  // array to be added here
        popupMenu.setOnMenuItemClickListener(new PopupMenu.OnMenuItemClickListener({
                // on click events for each item
        });
        return view;
    }
}

Answer 2

您可以定义如下界面

interface MenuItemProvider {
     getMenuItems(); // add parameters, returntype based on your need.
}

Activity实现此接口并通过返回在activity中准备的listItem来实现getMenuItems（）方法。

现在，您的适配器应该有一个setter方法来设置此接口，如下所示。

class yourActivity extends <> implements MenuItemProvider {

// other implementation.

// pass this implementation to your base adapter.
baseadapterinstance.setMenuItemProvider(this);


getMenuItems(){
 // return list items.
}



    }


/*** BaseAdpater class. ***/
private MenuItemProvider menuItemProviderImpl;

void setMenuItemProvider(MenuItemProvider menuItemProviderImpl){
this. menuItemProviderImpl = menuItemProviderImpl;
}

// when you need to get the list, call 
menuItemProviderImpl.getMenuItems();

希望这会有所帮助!!

如何访问List＆lt;＆gt;来自BaseAdapter类的活动java类中的数组

2 个答案: