Question

我正在制作墙纸应用程序，并且试图在代表类别的墙纸上使用类别文本制作类别部分（例如，文字-自然，图片-森林）。问题是，当我播放该应用程序时，什么都没有显示，但是也没有错误，一切都应该正常工作，但事实并非如此。

Firebase规则都已设置。

我已授权该应用访问互联网。

依赖项：

dependencies {
implementation 'com.squareup.picasso:picasso:2.71828'
implementation 'com.firebaseui:firebase-ui-database:3.+'
implementation fileTree(dir: 'libs', include: ['*.jar'])
implementation 'com.android.support:appcompat-v7:28.0.0'
implementation 'com.android.support:recyclerview-v7:28.0.0'
implementation 'com.android.support:cardview-v7:28.0.0'
implementation 'com.android.support:design:28.0.0'
implementation 'com.android.support.constraint:constraint-layout:1.1.3'
implementation 'com.android.support:design:28.0.0'
implementation 'com.android.support:support-v4:28.0.0'
testImplementation 'junit:junit:4.12'
androidTestImplementation 'com.android.support.test:runner:1.0.2'
androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
implementation 'com.google.firebase:firebase-database:16.0.1'
implementation 'com.google.firebase:firebase-core:16.0.5'
}

类别片段类别：

public class CategoryFragment extends Fragment {

    //Firebase
    FirebaseDatabase database;
    DatabaseReference categoryBackground;

    //FirebaseUI adapteris
    FirebaseRecyclerOptions<CategoryItem> options;
    FirebaseRecyclerAdapter<CategoryItem, CategoryViewHolder> adapter;
    //view
    RecyclerView recyclerView;


    private static CategoryFragment INSTANCE = null;

    public CategoryFragment() {
        // Required empty public constructor
        database = FirebaseDatabase.getInstance();
        categoryBackground = database.getReference(Common.STR_CATEGORY_BACKGROUND);


        options = new FirebaseRecyclerOptions.Builder<CategoryItem>()
                .setQuery(categoryBackground,CategoryItem.class)
                .build();

        adapter = new FirebaseRecyclerAdapter<CategoryItem, CategoryViewHolder>(options) {
            @Override
            protected void onBindViewHolder(@NonNull final CategoryViewHolder holder, int position, @NonNull final CategoryItem model) {

                Picasso.get()
                        .load(model.getImageLink())
                        .networkPolicy(NetworkPolicy.OFFLINE)
                        .into(holder.background_image, new Callback() {
                            @Override
                            public void onSuccess() {

                            }

                            @Override
                            public void onError(Exception e) {
                                //Bandyti dar karta online jeigu nepavyksta
                                Picasso.get()
                                        .load(model.getImageLink())
                                        .error(R.drawable.ic_error_black_24dp)
                                        .into(holder.background_image, new Callback() {
                                            @Override
                                            public void onSuccess() {

                                            }

                                            @Override
                                            public void onError(Exception e) {
                                                Log.e("ERROR_", "Couldn't fetch image");
                                            }
                                        });
                            }
                        });

                holder.category_name.setText(model.getName());

                holder.setItemClickListener(new ItemClickListener() {
                    @Override
                    public void onClick(View view, int position) {

                    }
                });
            }


            @Override
            public CategoryViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
                View itemView = LayoutInflater.from(parent.getContext())
                        .inflate(R.layout.layout_category_item, parent, false);
                return new CategoryViewHolder(itemView);
            }
        };
    }


    public static CategoryFragment getInstance()
    {

        if(INSTANCE == null)
            INSTANCE = new CategoryFragment();
        return INSTANCE;
    }

    @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 view = inflater.inflate(R.layout.fragment_category, container, false);
        recyclerView = (RecyclerView)view.findViewById(R.id.recycler_category);
        recyclerView.setHasFixedSize(true);
        GridLayoutManager gridLayoutManager = new GridLayoutManager(getActivity(),2);
        recyclerView.setLayoutManager((gridLayoutManager));

        setCategory();

        return view;

    }

    private void setCategory() {
        adapter.startListening();
        recyclerView.setAdapter(adapter);
    }

    @Override
    public void onStart() {
        super.onStart();
        if(adapter != null)
            adapter.startListening();
    }

    @Override
    public void onStop() {
        if(adapter != null)
            adapter.stopListening();
        super.onStop();
    }

    @Override
    public void onResume() {
        super.onResume();
        if(adapter != null)
            adapter.startListening();
    }
}

Answer 1

找到了一个解决方案，我已经花了几个小时没注意到字符串中的拼写错误。杀了我。

墙纸应用程序不显示Firebase中的图像

1 个答案: