android - 片段不能转换为上下文?
问题描述
我正在开发一个带有 Recyclerview + Cardview 和 GridLayout 的 Android 应用程序,我得到了标题中的错误。
Reminders.java(片段类)
public class Reminders extends Fragment {
private OnFragmentInteractionListener mListener;
List<reminder> lstreminder;
public Reminders() {
}
public static Reminders newInstance(String param1, String param2) {
Reminders fragment = new Reminders();
Bundle args = new Bundle();
fragment.setArguments(args);
return fragment;
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (getArguments() != null) {
}
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
lstreminder = new ArrayList<>();
lstreminder.add(new reminder("Alarms",R.drawable.alarms));
lstreminder.add(new reminder("Birthdays",R.drawable.birthdays));
lstreminder.add(new reminder("Anniversaries",R.drawable.anniversaries));
lstreminder.add(new reminder("Buy Gifts",R.drawable.buygift));
lstreminder.add(new reminder("Bill Payments",R.drawable.billpayments));
lstreminder.add(new reminder("Call / SMS",R.drawable.call));
lstreminder.add(new reminder("Recharges",R.drawable.recharges));
lstreminder.add(new reminder("Meetings",R.drawable.meetings));
lstreminder.add(new reminder("Insurance",R.drawable.insurances));
lstreminder.add(new reminder("Exams",R.drawable.exams));
lstreminder.add(new reminder("Holidays",R.drawable.holidays));
lstreminder.add(new reminder("Medical",R.drawable.medical));
lstreminder.add(new reminder("Purchase",R.drawable.purchase));
lstreminder.add(new reminder("Travel",R.drawable.travel));
lstreminder.add(new reminder("Tv Shows",R.drawable.shows));
RecyclerView recyclerView = (RecyclerView) getView().findViewById(R.id.mRecyclerView_id);
RecyclerviewAdapter recyclerviewAdapter = new RecyclerviewAdapter(this,lstreminder);
recyclerView.setLayoutManager(new GridLayoutManager(getActivity(),3));
recyclerView.setAdapter(recyclerviewAdapter);
return inflater.inflate(R.layout.fragment_reminders, container, false);
}
public void onButtonPressed(Uri uri) {
if (mListener != null) {
mListener.onFragmentInteraction(uri);
}
}
@Override
public void onAttach(Context context) {
super.onAttach(context);
if (context instanceof OnFragmentInteractionListener) {
mListener = (OnFragmentInteractionListener) context;
} else {
throw new RuntimeException(context.toString()
+ " must implement OnFragmentInteractionListener");
}
}
@Override
public void onDetach() {
super.onDetach();
mListener = null;
}
public interface OnFragmentInteractionListener {
void onFragmentInteraction(Uri uri);
}
}
RecyclerviewAdapter.java
public class RecyclerviewAdapter extends RecyclerView.Adapter<RecyclerviewAdapter.MyViewHolder>{
private Context mContext;
private List<reminder> mData;
public RecyclerviewAdapter(Reminders mContext, List<reminder> mData) {
this.mContext = mContext;
this.mData = mData;
}
@Override
public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view;
LayoutInflater inflater = LayoutInflater.from(mContext);
view = inflater.inflate(R.layout.cardview,parent,false);
return new MyViewHolder(view);
}
@Override
public void onBindViewHolder(MyViewHolder holder, int position) {
holder.mTextView.setText(mData.get(position).getmTitle());
holder.mImageView.setImageResource(mData.get(position).getmImages());
}
@Override
public int getItemCount() {
return mData.size();
}
public static class MyViewHolder extends RecyclerView.ViewHolder{
TextView mTextView;
ImageView mImageView;
public MyViewHolder(View itemView) {
super(itemView);
mTextView =(TextView)itemView.findViewById(R.id.mReminder_Text_Id);
mImageView =(ImageView)itemView.findViewById(R.id.mReminder_Image_Id);
}
}
}
在上面的代码中,我在这些行上得到了错误
public RecyclerviewAdapter(Reminders mContext, List<reminder> mData) {
this.mContext = mContext;
this.mData = mData;
}
错误:
error: incompatible types: Reminders cannot be converted to Context
谁能帮我解决这个问题。
解决方案
片段不扩展Context
。getActivity()
您可以使用;将片段的活动作为上下文传递
但是,您可以只调用适配器并从适配器parent.getContext()
中onCreateViewHolder(ViewGroup parent, int viewType_
删除上下文。
@Override
public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view;
LayoutInflater inflater = LayoutInflater.from(parent.getContext());
view = inflater.inflate(R.layout.cardview,parent,false);
return new MyViewHolder(view);
}
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