TextViewとImageViewを備えたCardViewを含む下部のナビゲーションフラグメントにRecyclerViewを実装したいと思います。また、新しいアクティビティを開くすべてのカードにonClickListenerがあります。しかし、私のrecyclerviewには何も表示されず、nullポイント例外が発生します Logcat 。ここで何が欠落しているかわかりません。
モデルクラス
class Data {
public int imageId;
public String txt;
Data( int imageId, String text) {
this.imageId = imageId;
this.txt = text;
}
}
RecyclerView Adapter
public class RecyclerViewAdapter extends RecyclerView.Adapter<RecyclerViewAdapter.MyViewHolder> {
List<Data> data ;
Context context;
public RecyclerViewAdapter(Context context, ArrayList<Data>data) {
this.context = context;
this.data = data;
}
public static class MyViewHolder extends RecyclerView.ViewHolder{
public CardView mCardView;
public TextView mTextView;
public ImageView imageView;
public MyViewHolder(View v){
super(v);
mCardView = (CardView) v.findViewById(R.id.cardview1);
mTextView = (TextView) v.findViewById(R.id.tv_text);
imageView = (ImageView) v.findViewById(R.id.iv_image);
}
}
@Override
public RecyclerViewAdapter.MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType){
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.recyclerview_items, parent, false);
MyViewHolder vh = new MyViewHolder(v);
return vh;
}
@Override
public void onBindViewHolder(final MyViewHolder holder, int position){
Data all = data.get(position);
holder.mTextView.setText(all.txt);
holder.imageView.setImageResource(all.imageId);
holder.itemView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
int position = holder.getAdapterPosition();
final Intent intent;
if (position == 0){
intent = new Intent(context, ShowDetails.class);
} else if (position == 1){
intent = new Intent(context, AllDetails.class);
} else {
intent = new Intent(context, RecentDetails.class);
}
context.startActivity(intent);
}
});
}
@Override
public int getItemCount()
{
return data.size();
}
}
MainActivity
RecyclerView recyclerView;
RecyclerView.Adapter adapter;
private List<Data> data;
public StatusFragment() {
// Required empty public constructor
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
// Inflate the layout for this fragment
View rootView = inflater.inflate(R.layout.fragment_status, container, false);
recyclerView = rootView.findViewById(R.id.recyclerView);
recyclerView.setHasFixedSize(true);
ArrayList<Data> data= new ArrayList<>();
data.add(new Data( R.drawable.bg, "Image 1"));
data.add(new Data( R.drawable.bg, "Image 2"));
data.add(new Data( R.drawable.bg, "Image 3"));
data.add(new Data( R.drawable.bg, "Image 1"));
data.add(new Data( R.drawable.bg, "Image 2"));
data.add(new Data( R.drawable.bg, "Image 3"));
data.add(new Data( R.drawable.bg, "Image 1"));
data.add(new Data( R.drawable.bg, "Image 2"));
data.add(new Data( R.drawable.bg, "Image 3"));
recyclerView.setAdapter(adapter);
adapter.notifyDataSetChanged();
LinearLayoutManager llm = new LinearLayoutManager(getActivity());
recyclerView.setLayoutManager(llm);
return rootView;
}
}
RecyclerViewAdapter
コンストラクターを呼び出していません:
この行をフラグメントに追加して呼び出しますadapter = new RecyclerViewAdapter (getActivity(), data);
RecyclerViewAdapter adapter;
LinearLayoutManager llm = new LinearLayoutManager(getActivity());
recyclerView.setLayoutManager(llm);
adapter = new RecyclerViewAdapter (getActivity(), data);
recyclerView.setAdapter(adapter);
adapter.notifyDataSetChanged();
return rootView;