如何将一个片段的回收器查看项目的值传递给另一个片段

Question

我很难理解如何将值从一个片段传递到另一个片段。我在回收站项目中创建了一个切换按钮，当检查时应该将卡片的内容传递给另一个实现recyclerVIew的碎片（收藏夹）。

这是我recyclerView适配器

public class RecyclerAdapter extends RecyclerView.Adapter<RecyclerAdapter.ViewHolder> { 
    private ClipboardManager myClipboard; 
    private ClipData myClip; 
    private Context context; 




    public List<CardItemModel> cardItems; 

    public RecyclerAdapter(List<CardItemModel> cardItems){ 
     this.cardItems = cardItems; 
    } 

    public static class ViewHolder extends RecyclerView.ViewHolder{ 
     ImageView copyButton; 
     ImageView shareButton; 
     ToggleButton favButton; 


     TextView title; 
     TextView content; 
     public ViewHolder(View itemView) { 
      super(itemView); 
      this.title = (TextView)itemView.findViewById(R.id.card_title); 
      this.content = (TextView)itemView.findViewById(R.id.card_content); 
      this.copyButton= (ImageView) itemView.findViewById(R.id.copyButton); 
      this.shareButton=(ImageView) itemView.findViewById(R.id.shareButton); 

      this.favButton=(ToggleButton) itemView.findViewById(R.id.favButton); 

      favButton.setChecked(false); 
      favButton.setBackgroundDrawable(ContextCompat.getDrawable(favButton.getContext(), R.mipmap.ic_launcher)); 


     } 
    } 



    @Override 
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { 
     View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.recycler_item,parent,false); 
     ViewHolder viewHolder = new ViewHolder(view); 
     return viewHolder; 
    } 

    @Override 
    public void onBindViewHolder(final ViewHolder holder, int position) { 
     holder.title.setText(cardItems.get(position).title); 
     holder.content.setText(cardItems.get(position).content); 
     holder.copyButton.setOnClickListener(new View.OnClickListener(){ 
      public void onClick(View v){ 


       myClipboard = (ClipboardManager) v.getContext().getSystemService(Context.CLIPBOARD_SERVICE); 


       myClip = ClipData.newPlainText("label", holder.content.getText().toString()); 
       myClipboard.setPrimaryClip(myClip); 
       Toast.makeText(v.getContext(), "Copied to clipboard" , Toast.LENGTH_SHORT).show(); 

      } 
     }); 
     holder.shareButton.setOnClickListener(new View.OnClickListener(){ 
      public void onClick(View v){ 
       Intent share = new Intent(Intent.ACTION_SEND); 
       share.setType("text/plain"); 
       share.putExtra(Intent.EXTRA_TEXT, holder.content.getText().toString()); 
       v.getContext().startActivity(Intent.createChooser(share, "Share Text")); 
      } 
     }); 

     holder.favButton.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener(){ 
      @Override 
      public void onCheckedChanged(CompoundButton favButton, boolean isChecked){ 
       if (isChecked) 
        favButton.setBackgroundDrawable(ContextCompat.getDrawable(favButton.getContext(),R.mipmap.ic_launcher)); 

       else 
        favButton.setBackgroundDrawable(ContextCompat.getDrawable(favButton.getContext(), R.mipmap.ic_cart)); 
      } 
     }); 
    } 

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

而这正是我想要passs值我的“收藏”的片段。

public class FavouriteFragment extends Fragment { 

    private List<CardItemModel> cardItems = new ArrayList<>(20); 
    private MainActivity mainActivity; 
    private Toolbar toolbar; 
    private RecyclerView recyclerView; 
    private RecyclerAdapter recyclerAdapter; 

    public FavouriteFragment() { 

    } 

    @Override 
    public void onAttach(Activity activity) { 
     super.onAttach(activity); 
     mainActivity = (MainActivity)activity; 
    } 

    @Override 
    public View onCreateView(LayoutInflater inflater, ViewGroup container, 
          Bundle savedInstanceState) { 

     View view = inflater.inflate(R.layout.fragment_favourite, container, false); 

     toolbar = (Toolbar)view.findViewById(R.id.fab_toolbar); 

     setupToolbar(); 



     recyclerView = (RecyclerView)view.findViewById(R.id.fab_recycler_view); 

     setupRecyclerView(); 

     return view; 
    } 

    @Override 
    public void onActivityCreated(Bundle savedInstanceState) { 
     super.onActivityCreated(savedInstanceState); 
     mainActivity.setupNavigationDrawer(toolbar); 
    } 

    private void setupToolbar(){ 
     toolbar.setTitle(getString(R.string.fav_fragment_title)); 
     mainActivity.setSupportActionBar(toolbar); 
    } 

    private void setupRecyclerView(){ 
     recyclerView.setLayoutManager(new LinearLayoutManager(mainActivity)); 
     recyclerView.setHasFixedSize(true); 
     initializeCardItemList(); 
     recyclerAdapter = new RecyclerAdapter(cardItems); 
     recyclerView.setAdapter(recyclerAdapter); 
    } 

    private void initializeCardItemList(){ 
     CardItemModel cardItemModel; 
     String[] cardTitles = getResources().getStringArray(R.array.fav_cards); 
     String[] cardContents = getResources().getStringArray(R.array.fav_cards_content); 
     final int length = cardTitles.length; 
     for(int i=0;i<length;i++){ 
      cardItemModel = new CardItemModel(cardTitles[i],cardContents[i]); 
      cardItems.add(cardItemModel); 
     } 
    } 



} 

Answer 1

片段之间的通信可以通过EventBus完成。 步骤： 1.创建事件类别 2.注册要更改片段数据的事件。 3.从片段发布事件（点击切换按钮）。

https://github.com/greenrobot/EventBus

http://greenrobot.org/eventbus/

第1步：

import java.io.Serializable; 

public class ToggleButtonClickEvent implements Serializable { 
private CardItemModel cardItemModel; 

public ToggleButtonClickEvent (CardItemModel ardItemModel){ 
    this.cardItemModel= cardItemModel; 
} 

public CardItemModel getCardItemModel() { 
    return cardItemModel; 
} 

}

第2步： 注册，并要更改数据

注销的片段事件

}

@Override 
    public void onStop() { 
    super.onStop(); 
    EventBus.getDefault().unregister(this); 
    } 

第3步：

事件后，当切换按钮点击

EventBus.getDefault().post(new ToggleButtonClickEvent(cardItemModel)); 

Answer 2

添加在捆绑

Fragment fragment = new Table_Selection_QRCODE(); 
          Bundle bun = new Bundle(); 
          bun.putString("table","20"); 
          fragment.setArguments(bun); 
getFragmentManager().beginTransaction().replace(R.id.frag, fragment).commit(); 

在其他片段你的价值观收到像这样的值（OnCreate）

@Override 
    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     Bundle b=getArguments(); 
     if(b!=null){ 
      rslt=b.getString("table",""); 
     } 
    } 

Answer 3

您可以使用该接口。让我们看一个例子，您想要从FragmentA向FragmentB传递值

class FragmentA extends Fragment{ 
    //Your fragment a functionalities goes here 
    //now define an interface inside this FragmentA 

    //you get reference from main activity 
    MainActivity activity; 
    @Override 
    void onCreate(){ 
    activity = getActivity(); 
    } 
//after your functionalities you can call passValue function of main activity from the variable 'activity' like 
    activity.passValue(your integer value from fragmentA to main activity) 

    interface OnValuePassedListener{ 
     void passValue(int value)//if you want to pass integer value 
     } 
    } 


    //this is the activity where FragmentA is located 

    public class MainActivity extends Activity implements FragmentA.OnValuePassedListener{ 
//Inside this activity, you write code to open the fragment. When you do that pass this activity's reference to the FragmentA 


    @Override 
    void passValue(int value){ 
    //you get the value from FragmentA inside this function 
     } 

    } 

您知道如何将值从活动传递给片段。从活动中的passValue（）函数中，可以调用另一个片段并将该值传递给片段。

通过这种方式，您可以使用Activity作为中间人将值从FragmentA传递到另一个片段。 你可以从这里了解更多关于https://www.youtube.com/watch?v=VyyGP_d0Ia8&index=118&list=PLonJJ3BVjZW6hYgvtkaWvwAVvOFB7fkLa