从 firebase 数据库检索数据到 textview 时如何创建换行符？

Question

我知道，如果我想创建一个新行，我必须在\n需要创建该行的任何位置插入。但我得到的是没有我在 firebase 数据库中已有的行的文本。有人可以告诉我如何解决这个问题吗？例如，如果我在数据库中有 hello \n world。我明白hello world了 当我真的应该得到它时

hello
world

我需要更改 firebase 或源代码中的某些内容吗？

这就是我从 firebase 获取数据的方式

  private void getData(){
        firebaseDatabaseInstance = FirebaseDatabase.getInstance();

        // get reference to 'users' node
        booksInstance = firebaseDatabaseInstance.getReference("monzmat");

        books.clear();
        books.addAll(db.getAllBookMonzmat());
        adapter = new qamoosAdapter(this, books);
        gridView.setAdapter(adapter);


        booksInstance.addValueEventListener(new ValueEventListener() {
            @Override
            public void onDataChange(DataSnapshot dataSnapshot) {
                storeData(dataSnapshot);
            }

            @Override
            public void onCancelled(DatabaseError error) {
                // Failed to read value
                Log.w(TAG, "Failed to read value.", error.toException());
            }
        });

        booksInstance.orderByChild("id").addChildEventListener(new ChildEventListener() {
            @Override
            public void onChildAdded(DataSnapshot dataSnapshot, String s) {
                qamoosData book = new qamoosData(
                        (String) dataSnapshot.child("id").getValue(),
                        (String) dataSnapshot.child("title").getValue(),
                        (String)dataSnapshot.child("content").getValue()


                );
                db.insertMonzmat(book);
                reloadData();
            }

            @Override
            public void onChildChanged(DataSnapshot dataSnapshot, String s) {
                qamoosData book = new qamoosData(
                        (String) dataSnapshot.child("id").getValue(),
                        (String) dataSnapshot.child("title").getValue(),
                        (String)dataSnapshot.child("content").getValue()

                );
                db.updateABookMonzmat(book);
                reloadData();
            }

            @Override
            public void onChildRemoved(DataSnapshot dataSnapshot) {
                qamoosData book = new qamoosData(
                        (String) dataSnapshot.child("id").getValue(),
                        (String) dataSnapshot.child("title").getValue(),
                        (String)dataSnapshot.child("content").getValue()
                );
                db.deleteABookMonzmat(book.getId());
                reloadData();
            }

            @Override
            public void onChildMoved(DataSnapshot dataSnapshot, String s) {

            }

            @Override
            public void onCancelled(DatabaseError databaseError) {

            }
        });
    }




    private void storeData(DataSnapshot snapshot) {
        books.clear();
        for (DataSnapshot alert: snapshot.getChildren()) {
            qamoosData book = new qamoosData(
                    (String)alert.child("id").getValue(),
                    (String)alert.child("title").getValue(),
                    (String)alert.child("content").getValue()

            );
            db.insertMonzmat(book);
        }
        books.addAll(db.getAllBookMonzmat());
        // Constants.hideDialog();

        adapter.notifyDataSetChanged();
    }

这是我的适配器

public class qamoosAdapter extends BaseAdapter {


    Activity activity;
    ArrayList<qamoosData> arrayList = new ArrayList<>();
    ArrayList<qamoosData> filterList = new ArrayList<>();

    LayoutInflater mLayoutInflater;
    DBHandler db;
    Storage storage;

    public qamoosAdapter(Activity context, ArrayList<qamoosData> bookDatas){
        this.activity = context;
        this.arrayList = bookDatas;
        this.db = new DBHandler(context);
        this.filterList= bookDatas;
        mLayoutInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        storage = SimpleStorage.getInternalStorage(context);
    }

    @Override
    public int getCount() {
        return arrayList.size();
    }

    @Override
    public Object getItem(int position) {
        return arrayList.get(position);
    }

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

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        qamoosAdapter.ViewHolder holder = new qamoosAdapter.ViewHolder();
        if (convertView == null) {
            convertView = mLayoutInflater.inflate(R.layout.fragment_qamoos, null);



            holder.name = (TextView) convertView.findViewById(R.id.bookName2_makotab_fragment);


            if(holder.name.getText().toString().contains("\n")){


            }

            convertView.setTag(holder);

        } else {
            holder = (qamoosAdapter.ViewHolder) convertView.getTag();
        }

        holder.name.setText(arrayList.get(position).getTitle());
        return convertView;
    }


    public class ViewHolder{

        ImageView image;

        TextView name;
    }

}

Answer 1

您可以放置​​特殊字符序列并在检索数据后替换它。Firebase 数据库不允许使用 \ 字符。

所以你可以在数据库中输入：Hello _b world

检索后，将此 _b 替换为 \n

Answer 2

Firestore 自动转换\n为\\n. 所以如果你想在Firestore中使用\n，请转换\\n成\n在android中。

textView.text = text.replace("\\n", "\n")

奖金

如果您使用数据绑定，则可以使用此绑定适配器

@JvmStatic
@BindingAdapter("text_parse_new_line")
fun parseNewLine(textView: TextView, text: String?) {
    textView.text = text?.replace("\\n", "\n")
}

在布局文件中使用

            <TextView
                android:id="@+id/how_to_claim"
                text_parse_new_line="@{viewModel.listing.howToClaim}" />