如何从适配器类中调用getSupportFragmentManager()方法？

Question

我在RecyclerView中将ViewPager设置为第一项。我想在onBindViewHolder()方法中为viewpager设置FragmentStatePagerAdapter，但我无法调用getsupportfragmentmanager()函数。请帮忙！！这是我的代码：

public class CustomListAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
    private Context context;
    private List<RowItem> rowItemList;
    private final int VIEW_TYPE_CUSTOM = 0;
    private final int VIEW_TYPE_NORMAL = 1;
    NewPagerAdapter mCustomPagerAdapter;

    public CustomListAdapter(Context context, List<RowItem> rowItemList) {
        this.context = context;
        this.rowItemList = rowItemList;
    }

    @Override
    public int getItemViewType(int position) {
        if (position == 0)
            return VIEW_TYPE_CUSTOM;
        else
            return VIEW_TYPE_NORMAL;
    }

    @Override
    public int getItemCount() {
        return rowItemList.size()+1;
    }

    @Override
    public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
        switch (getItemViewType(position)) {
            case VIEW_TYPE_CUSTOM:
                recViewHolder1 viewHolderSecond = (recViewHolder1) holder;
                    mCustomPagerAdapter = new NewPagerAdapter(getSupportFragmentManager());
                    viewHolderSecond.vPager.setAdapter(mCustomPagerAdapter);
                break;
            case VIEW_TYPE_NORMAL:
                recViewHolder2 viewHolderFirst = (recViewHolder2) holder;
                RowItem rowItem = rowItemList.get(position-1);
                viewHolderFirst.vName.setText(rowItem.getName());
                viewHolderFirst.vImage.setImageResource(rowItem.getImageId());
                break;

        }
    }

    @Override
    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        switch (viewType) {
            case VIEW_TYPE_CUSTOM:
                View itemView = LayoutInflater.
                        from(parent.getContext()).
                        inflate(R.layout.pagerlayout, parent, false);
                return new recViewHolder1(itemView);
            case VIEW_TYPE_NORMAL:
                View itemView1 = LayoutInflater.
                        from(parent.getContext()).
                        inflate(R.layout.rowlayout, parent, false);
                return new recViewHolder2(itemView1);
        }
        return null;
    }

    @Override
    public long getItemId(int position) {
        return super.getItemId(position);
    }


    public static class recViewHolder1 extends RecyclerView.ViewHolder {
        protected static ViewPager vPager;


        public recViewHolder1(View v) {
            super(v);
            vPager = (ViewPager) v.findViewById(R.id.vPager);
        }
    }

    public class recViewHolder2 extends RecyclerView.ViewHolder implements View.OnClickListener {
        protected  TextView vName;
        protected  ImageView vImage;

        public recViewHolder2(View v) {
            super(v);
            v.setOnClickListener(this);
            vName = (TextView) v.findViewById(R.id.vName);
            vImage = (ImageView) v.findViewById(R.id.vImage);
        } } }

- Nabin

---

你需要在构造函数中将它传递给来自Activity/Fragment的适配器。 - Logic

Answer 1

我通过转换mContext来解决了它。

((FragmentActivity)mContext).getSupportFragmentManager().beginTransaction()
                            .replace(R.id.item_detail_container, fragment)
                            .commit();

- Mostafa Anter

---

在这个提案中，我遇到了运行时错误MainActivity无法转换为android.support.v4.app.FragmentActivity。 - Josef Vancura

不可转换的类型。 - André Luiz Reis

Answer 2

最佳解决方案是将您的上下文引用从您的活动（或）片段传递给适配器。

    public UsersAdapter(ArrayList<User> items , Context context) {
    usersList = items;
    this.context = context;
    }

然后像这样将上下文向上转型为AppCompatActivity，然后获取getSupportFragmentManager。

    ((AppCompatActivity) context).getSupportFragmentManager()

分享以改进。

- Sheharyar Ejaz

---

Kotlin: val fm = (context as AppCompatActivity).supportFragmentManager。在适配器类中：class MyAdapter（ private val context: Context， - Shimon Rothschild

Answer 3

在这里，您可以设置过渡效果 ;)

public void pushFragment(Fragment newFragment, Context context){

    FragmentTransaction transaction = ((FragmentActivity)context).getSupportFragmentManager().beginTransaction();
    transaction.replace(R.id.fragment, newFragment);
    transaction.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
    transaction.addToBackStack(null);
    transaction.commit();

}

- Umberto Emonds

Answer 4

 FragmentManager fragmentManager = ((FragmentActivity) view.getContext()).getSupportFragmentManager();
                    FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();

试试这个……对我有用。

- payal_suthar

---

在我的代码中，view in view.getContext()是未解决的引用。 - morteza naji

Answer 5

我做过以下工作：

我按照以下步骤进行：

@Override
public void onBindViewHolder(DataAdapter.ViewHolder holder, final int position) {

        holder.txtTitle.setText(list.get(position).getTitle());
        holder.txtMessage.setText(list.get(position).getMessage());

        holder.cardView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                String title = list.get(position).getTitle();

                if(title.equals("FRECUENTES")){
                    RequestFrequentFragment fragment = new RequestFrequentFragment(); // you fragment 
                    FragmentManager fragmentManager = ((FragmentActivity) v.getContext()).getSupportFragmentManager(); // instantiate your view context
                    FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
                    fragmentTransaction.replace(R.id.nav_host_fragment, fragment);// your container and your fragment
                    fragmentTransaction.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
                    fragmentTransaction.addToBackStack(null);
                    fragmentTransaction.commit();

                }

            }
        });
}

- Zanyer

Answer 6

首先，您需要将上下文传递给适配器构造函数。

然后，您需要使用该上下文引用获取getSupportFragmentManager。

mCustomPagerAdapter = new NewPagerAdapter(context.getSupportFragmentManager());
viewHolderSecond.vPager.setAdapter(mCustomPagerAdapter);

- Arun Shankar

---

@Nabin 找到解决方案了吗？ - Burkely91

试一下这个...这对我有效...FragmentManager fragmentManager = ((FragmentActivity) view.getContext()).getSupportFragmentManager(); FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction(); - payal_suthar

Answer 7

另一个解决方案...

声明上下文

private Toast mssgeToast;

private Context ctxContext;

public MyViewListener(myView pView){

    this.mView = pView;
    this.ctxContext = pView.getContext();

}

接下来...

 public void pushFragment(Context context){
    FragmentManager fm = ((FragmentActivity)context).getSupportFragmentManager();
    PopupClickFragment pcf = new PopupClickFragment();

    pcf.show(fm, "");
   // FragmentTransaction transaction = ((FragmentActivity)context).getSupportFragmentManager().beginTransaction();

}

并将其声明为 onClickListener。 例如：

  @Override
    public void onCellClicked (@NonNull RecyclerView.ViewHolder p_jCellView,int p_nXPosition,
    int p_nYPosition){
        //TODO: AQUI SE DEBE LEVANTAR EL POPUP INSTANCIANDO .SHOW();

        pushFragment(ctxContext);
    }

- Ignacio_aa

Answer 8

如果你使用的是 Kotlin，可以使用以下解决方案：

val dialog = IntervAddFragment()
       val ft = (context as AppCompatActivity).supportFragmentManager.beginTransaction()
        dialog.show(ft, ContentValues.TAG)

并且它将会完美地运作，如果真主愿意的话。

- DINA TAKLIT

Answer 9

对于遇到这个错误的人：

无法转换类型；无法将'android.content.Context'转换为YourFragment

我实现了以下解决方案：

更新您的适配器构造函数以接受片段作为参数。

类似于：

customAdapter = new CustomAdapter(myContext, android.R.layout.simple_list_item_1
, getList, YourFragment.this);

并更新适配器的构造函数：

public CustomAdapter(Context context, int id, YourFragmentfragment) {
    this.fragment = fragment;
}

然后您可以使用片段变量调用方法。

fragment.doSomething();

答案由Shivam Verma提供。

- Roshna Omer

Answer 10

只需要通过 Activity。

   `public CustomListAdapter(AppCompatActivity context, List<RowItem> rowItemList) {
    this.context = context;
    this.rowItemList = rowItemList;
}`

您可以在适配器类中完成与活动相同的所有操作。

- milad parao