RecyclerView仅在编辑要添加的下一个项目时显示该项目

时间:2019-04-17 11:32:21

标签: java android xml android-recyclerview

我目前正在我的应用程序中建立一个活动,使用FAB添加产品。单击FAB会打开一个带有startActivityForResult的新弹出式活动,并在其中填充表格并通过Parcelable对象将其发送回去。

我现在面临的问题是,添加产品后,它没有显示在RecyclerView中,但是当我再次单击FAB时,第二个我开始编辑表单中的任何字段(例如,任何EditText) )针对下一个产品,我会在弹出式表格的背景中看到上一个产品。当我完成第二个产品时,直到我开始编辑第三个产品时,它才会出现,等等。

我遍历了XML,对我来说似乎还行。。。尝试读取几个解决方案(以及一次又一次地阅读我的代码),但是没有一个真正有用。

相关代码段(我在...中放了一些与本例无关的代码): 从主要活动(其中应显示产品):

'''

public class EditOffersActivity extends AppCompatActivity {
    ...
    private ArrayList<Offer> offers_list;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_edit_products);
        offers_list = new ArrayList<>();

        ...

        RecyclerView rvOffers = findViewById(R.id.offers_RecyclerView);
        OfferAdapter adapter = new OfferAdapter(offers_list);
        rvOffers.setAdapter(adapter);
        rvOffers.setLayoutManager( new LinearLayoutManager(this));

        // Setting up the FAB so it leads to the Product Details Pop-up
        FloatingActionButton fab = findViewById(R.id.fab);
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Intent intent = new Intent(EditOffersActivity.this, ProductDetailsPopupActivity.class);
                startActivityForResult(intent, HTZ_ADD_OFFER); // HTZ_ADD_OFFER = 1
            }
        });
    }

    @Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {
        Offer created_offer = data.getParcelableExtra("offer");
        offers_list.add(created_offer);
    }
}

'''

适配器: '''

public class OfferAdapter extends android.support.v7.widget.RecyclerView.Adapter<OfferAdapter.OfferViewholder> {
    private ArrayList<Offer> mOffers;

    public OfferAdapter(ArrayList<Offer> offers) {
        mOffers = offers;
    }

    @Override
    public OfferViewholder onCreateViewHolder(ViewGroup viewGroup, int viewType) {
        Context context = viewGroup.getContext();
        int layoutIdForListItem = R.layout.item_product;
        LayoutInflater inflater = LayoutInflater.from(context);

        View view = inflater.inflate(layoutIdForListItem, viewGroup, false);
        OfferViewholder viewHolder = new OfferViewholder(view);

        return viewHolder;
    }

    @Override
    public void onBindViewHolder(OfferViewholder holder, int position) {
        Offer current_offer = mOffers.get(position);
        ... // a lot of binding code
    }


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

    class OfferViewholder extends RecyclerView.ViewHolder {
        TextView name_TextView;
        TextView time_TextView;
        ...

        public OfferViewholder(View itemView) {
            super(itemView);

            // Init all views
            name_TextView = itemView.findViewById(R.id.product_item_name_TextView);
            time_TextView = itemView.findViewById(R.id.product_item_time_TextView);
             ...

        }
    }
}

'''

在用户单击“完成”后,弹出活动中的将其关闭的位: '''

mPublishButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if(p_photo_url == null) {
                ...
                } else {

                    // Create offer from user input
                    Offer n_offer = new Offer   (...)
                    );

                    ...

                    // Return offer to EditOffersActivity
                    Intent resultIntent = new Intent();
                    resultIntent.putExtra("offer", n_offer); // Offer is Parcelable
                    setResult(HTZ_ADD_OFFER, resultIntent);
                    finish();
                }
            }
        });

'''

还有RecyclerView的XML:

<android.support.v7.widget.RecyclerView xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/offers_RecyclerView"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    app:layoutManager="android.support.v7.widget.LinearLayoutManager"
    tools:itemCount="3"
    tools:listitem="@layout/item_product"
    tools:orientation="vertical"
    tools:scrollbars="horizontal"
    tools:spanCount="1">

3 个答案:

答案 0 :(得分:2)

您可以使用notifydatasetchanged如下代码:

mPublishButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if(p_photo_url == null) {
                ...
                } else {

                    // Create offer from user input
                    Offer n_offer = new Offer   (...)
                    );

                    ...

                    // Return offer to EditOffersActivity
                    Intent resultIntent = new Intent();
                    resultIntent.putExtra("offer", n_offer); // Offer is Parcelable
                    setResult(HTZ_ADD_OFFER, resultIntent);
                    OfferAdapter.notifydatasetchanged();
                    finish();
                }
            }
        });

OfferAdapter.notifydatasetchanged(); //方法将刷新您在视图中设置的适配器。值将刷新。

别忘了欣赏和喜欢答案。

答案 1 :(得分:1)

在适配器上添加如下方法:

public void update(ArrayList<Offer> offers){
            mOffers = offers;
        }

更新您的onActivityResult并像这样通知适配器:

@Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {
        Offer created_offer = data.getParcelableExtra("offer");
        offers_list.add(created_offer);
        adpater.update(offers_list);
        adapter.notifydatasetchanged();
    }

答案 2 :(得分:0)

添加到ArrayList后,您必须通过调用RecyclerViewAdapter的 notifydatasetchanged()

来通知对适配器的更改

喜欢:

adapter.notifydatasetchanged()