Question

我正在关注这个Android教程

https://github.com/udacity/ud851-Exercises/blob/student/Lesson03-Green-Recycler-View/T03.07-Solution-RecyclerViewClickHandling/app/src/main/java/com/example/android/recyclerview/MainActivity.java

为了在教程中的RecyclerView.Adapter（实例GreenAdapter）中处理项目点击，我们创建了一个接口来接收来自活动的onclick消息。然后，我们通过覆盖onListItemClick来实现MainActivity中的接口。代码如下所示

public class GreenAdapter extends RecyclerView.Adapter<GreenAdapter.NumberViewHolder> {
public interface ListItemClickListener {
    void onListItemClick(int clickedItemIndex);
}  
final private ListItemClickListener mOnClickListener;
public GreenAdapter(int numberOfItems, ListItemClickListener listener) {
    mNumberItems = numberOfItems;
    mOnClickListener = listener;
    viewHolderCount = 0;
}}

和活动

public class MainActivity extends AppCompatActivity implements GreenAdapter.ListItemClickListener {
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main); 
mAdapter = new GreenAdapter(NUM_LIST_ITEMS, this);}

this 指的是活动实例，但GreenAdapter构造函数采用ListItemClickListener类型。

这怎么可能。如何将活动作为ListItemClickListener类型传递/转换。

Answer 1

此处MainActivity表示您的ListItemClickListener已实施class Program { static void main(string[] args) { ObjectManager objects = new ObjectManager(); objects.AddObject(objects.CreateObject("object 1")); objects.AddObject(objects.CreateObject("object 2")); objects.AddObject(objects.CreateObject("object 3")); } } class ObjectManager { public List<Object> Objects { get; set; } public ObjectManager() { Objects = new List<Object>(); } public Object CreateObject(string name) { Object o = new Object(name); return o; } public void AddObject(Object o) { Objects.Add(o); } }。请阅读官方文档中的Android文档。

将MainActivity作为参数在android中传递RecyclerView Adapter

1 个答案: