android - 使用自定义项目 View 从 ListView 中获取项目

Question

我在 android 中有一个 ListView ，它的适配器如下所示:mRecipes 是 Recipe[] 类型。

 Recipe[] mRecipes;


public void onActivityCreated(Bundle savedInstanceState) {
    // TODO Auto-generated method stub

    super.onActivityCreated(savedInstanceState);

    // set adapter and ListView
    RecipeAdapter adapter = new RecipeAdapter(getActivity(),
            R.layout.listview_item_row, mRecipes);
    mListView = (ListView) getView().findViewById(R.id.lvMainDishes);

    mListView.setAdapter(adapter);
    mListView.setOnItemClickListener(this);
}

如您所见，我为列表中的每个项目创建了一个自定义 XML View 。

我希望能够从 OnItemClick 上的配方数组中获取配方对象

public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, long arg3) {
    // get the clicked recipe object here

}

有什么想法吗？谢谢!

Answer 1

如果您不希望有适配器实例变量，那么您的 onItemClick 实现可能如下所示:

@Override
public void onItemClick(AdapterView <?> parent, View view, int position, long id) {
    Recipe r = (Recipe) parent.getAdapter().getItem(position);
}

为了扩展 Pedro Oliveira 所说的话，另一个标准习语是这样的:

private RecipeAdapter mAdapter;

@Override
public void onActivityCreated(Bundle savedInstanceState) {
    super.onActivityCreated(savedInstanceState);

    mAdapter = new RecipeAdapter(getActivity(), R.layout.listview_item_row, mRecipes);
    mListView = (ListView) getView().findViewById(R.id.lvMainDishes);
    mListView.setAdapter(adapter);
    mListView.setOnItemClickListener(this);
}

@Override
public void onItemClick(AdapterView <?> parent, View view, int position, long id) {
    Recipe r = (Recipe) mAdapter.getItem(position);
}

如果您在 RecipeAdapter 中创建一个 getter 方法，则可以避免转换，例如:

public class RecipeAdapter extends BaseAdapter {

    // Implementation

    public Recipe get(int position) {
        return mRecipe[position]; // or maybe mList.get(position);
    }

}

然后，您的 onItemClick 归结为:

@Override
public void onItemClick(AdapterView <?> parent, View view, int position, long id) {
    Recipe r = mAdapter.get(position);
}