java - Android：传递允许recyclerview由特定字符串填充的变量

Question

我正在尝试创建一个代码，上面写着“登录的用户名与创建的配方的用户名相匹配，仅在我的 MyRecipes.java 活动的 recyclerview 中显示这些数据库条目”。我无法确定将这个潜在声明放在哪里。查看我的代码，如果或其他情况，您会将该语句放在哪里？

userLoggedIn 和 loggedUser 是当前登录用户的变量。

thisUser 是我设置为当 recyclerview 在 recyclerview.java 类中填充时从数据库中提取的用户。

任何帮助将不胜感激！

RecyclerView.java 类

    private static String thisUser;
    String userLoggedIn = HomeActivity.getUserLogged();
    private Context mContext;
    private RecipesAdapter mRecipeAdapter;

    public void setConfig (RecyclerView recyclerView, Context context, List<Recipes> recipes, List<String> keys){

        mContext = context;
        mRecipeAdapter = new RecipesAdapter(recipes, keys);
        recyclerView.setLayoutManager(new LinearLayoutManager(context));
        recyclerView.setAdapter(mRecipeAdapter);
    }

    class RecipeItemView extends RecyclerView.ViewHolder{
        private TextView mTitle;
        private TextView mIngredients;
        private TextView mMethod;
        private TextView mUser;
        private String key;

        public RecipeItemView(ViewGroup parent){
            super(LayoutInflater.from(mContext).inflate(R.layout.recipe_list_item, parent,false));

            mTitle = (TextView) itemView.findViewById(R.id.tvTitle);
            mMethod = (TextView) itemView.findViewById(R.id.tvMethod);
            mIngredients = (TextView) itemView.findViewById(R.id.tvIngredients);
            mUser = (TextView) itemView.findViewById(R.id.tvUser);

            itemView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    Intent intent = new Intent(mContext, RecipeDetails.class);
                    intent.putExtra("key", key);
                    intent.putExtra("title", mTitle.getText().toString());
                    intent.putExtra("ingredients", mIngredients.getText().toString());
                    intent.putExtra("method", mMethod.getText().toString());

                    mContext.startActivity(intent);
                }
            });
        }

        public void bind(Recipes recipes, String key) {

                mTitle.setText(recipes.getTitle());
                mIngredients.setText(recipes.getIngredients());
                mMethod.setText(recipes.getMethod());
                mUser.setText(recipes.getCreatedUser());
                thisUser = mUser.getText().toString().trim();
                this.key = key;
            }
    }

    public static String getUserLoggedIn(){
        return thisUser;
    }

    class RecipesAdapter extends RecyclerView.Adapter<RecipeItemView> {
        private List<Recipes> mRecipeList;
        private List<String> mKeys;

        public RecipesAdapter(List<Recipes> mRecipeList, List<String> mKeys) {
            this.mRecipeList = mRecipeList;
            this.mKeys = mKeys;
        }

        @NonNull
        @Override
        public RecipeItemView onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
            return new RecipeItemView(parent);
        }

        @Override
        public void onBindViewHolder(@NonNull RecipeItemView holder, int position) {
            holder.bind(mRecipeList.get(position), mKeys.get(position));
        }

        @Override
        public int getItemCount() {
            return mRecipeList.size();
        }
    }
}

MyRecipes.java（回收器视图填充并显示所有食谱的位置）

    String loggedUser = HomeActivity.getUserLogged();
    String thisUser = RecyclerViewConfig.getUserLoggedIn();
    Button addRecipes;
    private RecyclerView mRecyclerView;
    private String passedUsername;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_my_recipes);

        passedUsername = getIntent().getStringExtra("loggedUsername1");
        mRecyclerView = (RecyclerView) findViewById(R.id.rvRecipes);
        new FirebaseDatabaseHelper().readRecipes(new FirebaseDatabaseHelper.DataStatus() {
            @Override
            public void DataIsLoaded(List<Recipes> recipes, List<String> keys) {
                    new RecyclerViewConfig().setConfig(mRecyclerView, MyRecipesActivity.this, recipes, keys);
                }

            @Override
            public void DataIsInserted() {
            }

            @Override
            public void DataIsUpdated() {
            }

            @Override
            public void DataIsDeleted() {
            }
        });

        addRecipes = findViewById(R.id.btnAddNewRecipe);
        addRecipes.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent addrecipe = new Intent(MyRecipesActivity.this, AddRecipes.class);
                addrecipe.putExtra("loggedUsername2", passedUsername);
                startActivity(addrecipe);
            }
        });
    }
}

标签： javaandroidfirebase-realtime-databaseandroid-recyclerview

Answer 1

如果我理解正确，只有当他/她是创建食谱的人时，您才需要向用户展示食谱？假设，下面的代码更改将起到作用。

如下更改您的 bind() 方法。

public void bind(Recipes recipes, String key) {
        thisUser = mUser.getText().toString().trim();
        if(thisUser.equals(recipes.getCreatedUser)) {
           mTitle.setText(recipes.getTitle());
           mIngredients.setText(recipes.getIngredients());
           mMethod.setText(recipes.getMethod());
           mUser.setText(recipes.getCreatedUser());
           this.key = key;
        }
}

虽然这是一种幼稚的方法，但更好的方法是在您使用 readRecipes() 方法本身从 Firebase 加载数据时使用创建的用户过滤食谱列表。为此，可以按如下方式使用查询（根据您的数据库结构，下面的确切查询可能对您不起作用。根据需要进行更改）

Query query = reference.child("Recipes").orderByChild("userCreated").equalTo(thisUser);