适配器和片段发生了我无法理解的事情 [英] Adapter and Fragment Something incomprehensible to me happens

问题描述

问题是，当我将类别ID从适配器发送到MainFragment中的getDishes时，即使在getDishes
中CategoryId值发生了变化，我也无法从屏幕上的Dishes中看到任何内容，我希望代码能阐明事项
谢谢

The problem is when I send the CategoryId from the adapter to the getDishes in the MainFragment, I cannot see anything from the Dishes on the screen even though the CategoryId value changes within the getDishes I hope the code clarifies the matter Thank you

在MainFragment内部

Inside MainFragment

public class MainFragment extends Fragment
{
public void getCategory()
{
    categoryViewModel.getAll().observe(this, new Observer<List<Category>>() {
        @Override
        public void onChanged(List<Category> categories) {
            MainFragment.this.categories= categories;
            categoryAdapter.SetData(categories);
            if(categories.size() != 0)
            {
                selectedCategoryID = categories.get(0).getId();
                getDishes(selectedCategoryID);
            }
            else
            {
                dishes = new ArrayList<>();
                mainFragmentDishesAdapter.sSetData(dishes);
            }
        }
    });
}

我设置了一个Toast来查看CategoryId值是否正在更改，并且是否正在更改

I set a Toast to see if the CategoryId value is changing or not and it is

public void getDishes(final int CategoryIdd)
{
    selectedCategoryID = CategoryIdd;

    dishesViewModel.getAll(CategoryIdd).observe(this, new Observer<List<Dishes>>() {
        @Override
        public void onChanged(List<Dishes> dishes)
        {
            if(dishes.size() == 0)
            MainFragment.this.dishes = dishes;
            mainFragmentDishesAdapter.sSetData(dishes);
            Toast.makeText(getActivity(), ""+CategoryIdd, Toast.LENGTH_SHORT).show();
        }
    });
}

在适配器内部

public class MainFragmentCategoryAdapter extends RecyclerView.Adapter<MainFragmentCategoryVH>
{
public CallDishesBack mCallDishesBack;

public interface CallDishesBack { void getDishes(int CategoryIdd);}

mCallDishesBack = (CallDishesBack) context;

holder.getView().setOnClickListener(
     new View.OnClickListener()
      {
        @Override
        public void onClick(View view)
        {
            
         mCallDishesBack.getDishes(category.getId());
        }
    });


public void SetData(List<Category> categories)
{
    this.categories =  categories;
    notifyDataSetChanged();
}

在接口的MainActivity内部

Inside the MainActivity for the interface

public class MainActivity extends AppCompatActivity implements MainFragmentCategoryAdapter.CallDishesBack
{

MainFragment mainFragment;


        if(savedInstanceState == null){
        mainFragment = MainFragment.newInstance(new Bundle()); // use real bundle here
        getSupportFragmentManager()
                .beginTransaction()
                .add(R.id.content, mainFragment, "FragMain").commit();
    }


    public void getDishes(int CategoryIdd) {
    if(mainFragment != null)
    {
         mainFragment.getDishes(CategoryIdd);
    }

}

仅出现第一个类别的菜肴

Only the dishes for the first Category appear

如果不是这样，我希望问题很清楚，我在这里，非常感谢

I hope that the problem is clear if it is not like that, I am here and thank you very much

推荐答案

使用接口
是我的错误，我与BottomSheet或其他任何接口一起使用。我不知道还有使用界面
的另一种方法，旧方法效果不佳

It was my mistake when I used the Interface The one that I use with BottomSheet or anything else. I did not know that there is another way to use the interface The old method was not working well

适配器的第一步

public CallDishesYes mCallDishesYes;

public MainFragmentCategoryAdapter(Context context, List<Category> categories,CallDishesYes mCallDishesYes) {
    this.context = context;
    this.categories = categories;
    this.mCallDishesYes = mCallDishesYes;
}

    holder.getView().setOnClickListener(
       new View.OnClickListener()
    {
        @Override
        public void onClick(View view)
        {
            ///region Old solution that didn't work
            //mCallDishesBack.getDishes(category.getId());
            ///endregion
            mCallDishesYes.getDishes(category.getId());
        }
    });

public interface CallDishesYes {
    void getDishes(int IdCategory);
}

分段拖曳

public class MainFragment extends Fragment implements MainFragmentCategoryAdapter.CallDishesYes
{

dishes = new ArrayList<>();
mainFragmentDishesAdapter = new MainFragmentDishesAdapter(getActivity(),dishes);

    public void getDishes(int CategoryIdd)
{
    dishesViewModel.getAll(CategoryIdd).observe(this, new Observer<List<Dishes>>() {
        @Override
        public void onChanged(List<Dishes> dishes)
        {
            if (dishes.size() == 0)
            MainFragment.this.dishes = dishes;
            mainFragmentDishesAdapter.sSetDate(dishes);
        }
    });
}

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