Question

当我点击自动填充建议项目时，我正在尝试获取firebase数据库值。下面的代码是我试图实现它的方式。但是，我似乎在这一行上收到java.lang.String cannot be cast to SearchInformation错误：

sInfo = (SearchInformation) adapterView.getAdapter().getItem(i);

我正在关注this示例中的第一个答案。

注意：我不知道这是否是使用自动完成功能从firebase数据库检索信息的正确方法，但为了找到答案，我需要先解决这个问题。

代码：

public class Hot extends Fragment {

    private SearchInformation sInfo;
    private DatabaseReference database;


    public Hot() {
        // Required empty public constructor
    }


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

        View rootView = inflater.inflate(R.layout.fragment_hot, container, false);

        database = FirebaseDatabase.getInstance().getReference();

        final ArrayAdapter<String> autoComplete = new ArrayAdapter<>(getContext(), android.R.layout.simple_list_item_1);

        database.child("AutoCompleteOptions").addValueEventListener(new ValueEventListener() {
            @Override
            public void onDataChange(DataSnapshot dataSnapshot) {

                for (DataSnapshot suggestionSnapshot : dataSnapshot.getChildren()){

                    sInfo = suggestionSnapshot.getValue(SearchInformation.class);

                    autoComplete.add(sInfo.getEatery_name());
                }
            }

            @Override
            public void onCancelled(DatabaseError databaseError) {

            }
        });
        AutoCompleteTextView ACTV= rootView.findViewById(R.id.actv);
        ACTV.setAdapter(autoComplete);
        ACTV.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {

                sInfo = (SearchInformation) adapterView.getAdapter().getItem(i); // ** ERROR HERE **
                String anID = sInfo.getEatery_id(); 

                Log.i("ID is", anID);

            }
        });
        return rootView;
    }

}

数据模型：

public class SearchInformation {

    private String eatery_name;
    private String eatery_id;

    public SearchInformation() {

    }

    public SearchInformation(String eatery_name, String eatery_id) {
        this.eatery_name = eatery_name;
        this.eatery_id = eatery_id;

    }

    public String getEatery_name() {
        return eatery_name;
    }

    public void setEatery_name(String eatery_name) {
        this.eatery_name = eatery_name;
    }

    public String getEatery_id() {
        return eatery_id;
    }

    public void setEatery_id(String eatery_id) {
        this.eatery_id = eatery_id;
    }

}

Answer 1

您需要将SELECT user.* FROM user WHERE op_id IN ( SELECT user.op_id AS op_id FROM user WHERE last_login_on IS NOT NULL GROUP BY op_id HAVING SUM(IF(DATE(last_login_on) > DATE(DATE_SUB(NOW(), INTERVAL 31 DAY)), 1, 0)) = 0 ORDER BY op_id ASC ) AND role_type = 'owner'更改为自定义适配器ArrayAdapter<String>。然后使用ArrayAdapter<SearchInformation>，您可以使用autoComplete.add(sInfo)

获取SearchInformation的整个对象

Answer 2

那是因为它是ArrayAdapter<String>，其中有字符串。因此，您的getItem()也会为您提供字符串。

java.lang.String无法强制转换为

2 个答案: