我有一个实现 RecyclerView.Adapter 的类，并在 onBindViewHolder 中调用 onClick 侦听器来访问另一个片段。我有这个错误仍然存在并指向上下文。下面的代码片段：
((FragmentActivity)context).getSupportFragmentManager().beginTransaction()
.replace(R.id.container, fragment)
.commit();
我已经在全球范围内实施了我的上下文，并且被告知这不是好的做法。以下是我需要访问的完整课程和片段课程。
public class Topdeal_CustomAdapter extends RecyclerView.Adapter<Topdeal_CustomAdapter.ViewHolder> {
public static final String CATEGORY_NAME = "name";
public static final String CATEGORY_IMAGE = "image";
public static final String the_Id = "000000000";
private List<Categories_ItemObject> categories_List;
private Context context;
public Topdeal_CustomAdapter(List<Categories_ItemObject> developersLists, Context context) {
this.categories_List = developersLists;
this.context = context;
}
@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.single_topdeal, parent, false);
return new Topdeal_CustomAdapter.ViewHolder(v);
}
@Override
public void onBindViewHolder(final ViewHolder holder, int position) {
final Categories_ItemObject developersList = categories_List.get(position);
holder.name.setText(developersList.getCategoryName());
Picasso.with(context).load(developersList.getCategoryPicture()).into(holder.picture);
holder.picture.setOnClickListener(new View.OnClickListener(context) {
@Override
public void onClick(View v) {
TopDeal_two fragment = new TopDeal_two();
Bundle bundle = new Bundle();
bundle.putString(CATEGORY_NAME, developersList.getCategoryName());
fragment.setArguments(bundle);
((FragmentActivity)context).getSupportFragmentManager().beginTransaction()
.replace(R.id.container, fragment)
.commit();
}
});
}
@Override
public int getItemCount() {
return categories_List.size();
}
public class ViewHolder extends RecyclerView.ViewHolder {
ImageView picture;
TextView name;
LinearLayout relativeLayout;
public ViewHolder(View itemView) {
super(itemView);
picture = itemView.findViewById(R.id.category_image);
name = itemView.findViewById(R.id.category_name);
relativeLayout = itemView.findViewById(R.id.linearLayout_category);
}
}
}
要访问的片段类
public class TopDeal_two extends Fragment {
private RecyclerView recyclerView2;
private RecyclerView.Adapter adapter2;
private List<Album> BrandLists;
private static final String URL_DATA = "https://biz-point.herokuapp.com/brands";
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.top_deal_two, container, false);
Bundle arguments = getArguments();
if(arguments != null) {
final String catName = arguments.getString(Categories_customAdapter.CATEGORY_NAME);
String URL_DATA1 = URL_DATA.trim() + '/' + catName;
String URL_DATA2 = URL_DATA1.replaceAll(" " ,"%20");
loadClickedCategory(URL_DATA2);
getActivity().setTitle(catName);
recyclerView2 = view.findViewById(R.id.recyclerview_top_Two);
BrandLists = new ArrayList<>();
RecyclerView.LayoutManager mLayoutManager = new GridLayoutManager(getActivity(), 3);
recyclerView2.setLayoutManager(mLayoutManager);
recyclerView2.addItemDecoration(new TopDeal_two.GridSpacingItemDecoration(3, 0, true));
recyclerView2.setItemAnimator(new DefaultItemAnimator());
recyclerView2.setAdapter(adapter2);
}
return view;
}
private void loadClickedCategory(final String category) {
StringRequest stringRequest = new StringRequest(Request.Method.GET,
category, new Response.Listener<String>() {
@Override
public void onResponse(String response) {
// progressDialog.dismiss();
try {
JSONArray array = new JSONArray(response);
for (int i = 0; i < array.length(); i++){
JSONObject jo = array.getJSONObject(i);
String id = jo.getString("_id");
String b_name = jo.getString("brandName");
Double b_price = jo.getDouble("brandPrice");
String b_spec = jo.getString("brandSpecification");
String b_desc = jo.getString("brandDescription");
String b_image1 = jo.getString("brandImage_1").trim();
String image1 = category + '/' + id + '/' + b_image1;
Album developers = new Album(b_name, image1,b_price, b_spec, b_desc);
BrandLists.add(developers);
}
adapter2 = new Brands_CustomAdapter(BrandLists, getActivity().getApplicationContext());
recyclerView2.setAdapter(adapter2);
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
Toast.makeText(getActivity(), "Error" + error.toString(), Toast.LENGTH_SHORT).show();
}
});
RequestQueue requestQueue = Volley.newRequestQueue(getActivity());
requestQueue.add(stringRequest);
}
public class GridSpacingItemDecoration extends RecyclerView.ItemDecoration {
private int spanCount;
private int spacing;
private boolean includeEdge;
public GridSpacingItemDecoration(int spanCount, int spacing, boolean includeEdge) {
this.spanCount = spanCount;
this.spacing = spacing;
this.includeEdge = includeEdge;
}
@Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
int position = parent.getChildAdapterPosition(view); // item position
int column = position % spanCount; // item column
if (includeEdge) {
outRect.left = spacing - column * spacing / spanCount; // spacing - column * ((1f / spanCount) * spacing)
outRect.right = (column + 1) * spacing / spanCount; // (column + 1) * ((1f / spanCount) * spacing)
if (position < spanCount) { // top edge
outRect.top = spacing;
}
outRect.bottom = spacing; // item bottom
} else {
outRect.left = column * spacing / spanCount; // column * ((1f / spanCount) * spacing)
outRect.right = spacing - (column + 1) * spacing / spanCount; // spacing - (column + 1) * ((1f / spanCount) * spacing)
if (position >= spanCount) {
outRect.top = spacing; // item top
}
}
}
}
}
主要问题在 FragmentActivity... getSupportFragmentManager ....