android - 使用搜索 View 过滤自定义列表项

Question

我正在开发一个在工具栏中具有搜索 View 的聊天 Activity 。我想过滤包含查询的消息，但我无法让它工作。当我点击搜索按钮时，所有消息都消失了。知道我做错了什么吗？

Activity :

package com.zen.msy.activity;

import android.app.SearchManager;
import android.content.Context;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.Toolbar;
import android.text.TextUtils;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.inputmethod.InputMethodManager;
import android.widget.EditText;
import android.widget.ImageButton;
import android.widget.ListView;
import android.support.v7.widget.SearchView;
import android.widget.Toast;

import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.auth.FirebaseUser;
import com.google.firebase.database.DataSnapshot;
import com.google.firebase.database.DatabaseError;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;
import com.google.firebase.database.ValueEventListener;
import com.zen.msy.R;
import com.zen.msy.adapter.ChatAdapter;
import com.zen.msy.util.Message;

import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;

public class ChatActivity extends AppCompatActivity {

    Toolbar forum_toolbar;
    private FirebaseDatabase db;
    private DatabaseReference dbRef;
    private FirebaseUser fUser;
    private ArrayList<Message> chatLists = new ArrayList<>(); //arraylist containing the messages
    private ChatAdapter chatAdapter;
    private ListView chatList; //listview containing the chat bubbles
    private ImageButton floatingActionButton;
    private EditText inputChat;
    MenuItem searchButton;
    SearchView searchView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_chat);

        forum_toolbar = findViewById(R.id.toolbar);
        setSupportActionBar(forum_toolbar);

        chatList = findViewById(R.id.chat_list);
        inputChat = findViewById(R.id.inputChat);
        floatingActionButton = findViewById(R.id.fab);

        db = FirebaseDatabase.getInstance();
        fUser = FirebaseAuth.getInstance().getCurrentUser();
        dbRef = db.getReference("chats");

        chatAdapter = new ChatAdapter(getApplicationContext(),fUser,chatLists);
        chatList.setAdapter(chatAdapter);

        getSupportActionBar().setTitle("Forums");

        //Load messages from db
        dbRef.addValueEventListener(new ValueEventListener() {
            @Override
            public void onDataChange(DataSnapshot dataSnapshot) {
                chatLists.clear();

                for(DataSnapshot ds : dataSnapshot.getChildren()){
                    Message message = ds.getValue(Message.class);
                    chatLists.add(message);
                    // Log.d("VALUE",ds.getValue(Message.class).getText());
                }
                chatAdapter.notifyDataSetChanged();
                scrollMyListViewToBottom();
            }

            @Override
            public void onCancelled(DatabaseError databaseError) {

            }
        });

        //When user presses send
        floatingActionButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                if(inputChat.getText().length()>=6){

                    long msTime = System.currentTimeMillis();
                    Date curDateTime = new Date(msTime);
                    // SimpleDateFormat formatter = new SimpleDateFormat("dd'/'MM'/'y hh:mm");
                    SimpleDateFormat formatter = new SimpleDateFormat("hh:mm");

                    String dateTime = formatter.format(curDateTime);

                    //using PATIENT_NAME and PATIENT_MAIL for the message data
                    Message message = new Message(inputChat.getText().toString(),MainActivity.currentUserName,MainActivity.currentUserMail,dateTime);
                    dbRef.push().setValue(message);
                    inputChat.setText("");

                    InputMethodManager inputManager = (InputMethodManager) getApplicationContext().getSystemService(Context.INPUT_METHOD_SERVICE);
                    inputManager.hideSoftInputFromWindow(inputChat.getWindowToken(),InputMethodManager.HIDE_NOT_ALWAYS);

                }else{

                    Toast.makeText(getApplicationContext(),"Gönderilecek mesaj uzunluğu en az 6 karakter olmalıdır!",Toast.LENGTH_SHORT).show();
                }


            }
        });





    }



    private void scrollMyListViewToBottom() {
        chatList.post(new Runnable() {
            @Override
            public void run() {
                // Select the last row so it will scroll into view...
                chatList.setSelection(chatAdapter.getCount() - 1);
            }
        });
    }



    //Inflate the toolbar
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.toolbar,menu);
        MenuItem doneBtn = menu.findItem(R.id.symptomSendButton);
        searchButton = menu.findItem(R.id.action_search);
        doneBtn.setVisible(false);
        searchButton.setVisible(true);

        SearchView searchView = (SearchView) searchButton.getActionView();
        searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
            @Override
            public boolean onQueryTextSubmit(String s) {
                return false;
            }

            @Override
            public boolean onQueryTextChange(String s) {
                chatAdapter.getFilter().filter(s);
                return false;
            }
        });

        return true;
    }





}

自定义 ListView 的适配器:

package com.zen.msy.adapter;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.Filterable;
import android.widget.TextView;

import com.google.firebase.auth.FirebaseUser;
import com.zen.msy.R;
import com.zen.msy.util.Message;
import android.widget.Filter;

import java.util.ArrayList;
import java.util.List;



public class ChatAdapter extends ArrayAdapter<Message> implements Filterable {

    ArrayList<Message>  data;
    ArrayList<Message>  origData;

    private FirebaseUser firebaseUser;

    public ChatAdapter(Context context, FirebaseUser firebaseUser, ArrayList<Message> chatlist){
        super(context, 0, chatlist);
        this.firebaseUser = firebaseUser;

        this.data = chatlist;
        this.origData = new ArrayList<Message>(this.data);
    }


    @Override
    public View getView(final int position, View convertView, ViewGroup parent){


        Message message = getItem(position);


       // System.out.println("**********UID IS :"+firebaseUser.getUid());

        if (firebaseUser.getEmail().equalsIgnoreCase(message.getSenderMail())){

            convertView = LayoutInflater.from(getContext()).inflate(R.layout.right_item_layout, parent, false);


            TextView txtMessage =  convertView.findViewById(R.id.txtMessageRight);
            TextView txtTime =  convertView.findViewById(R.id.txtTimeRight);


            txtMessage.setText(message.getText());
            txtTime.setText(message.getTime());

        }else{

            convertView = LayoutInflater.from(getContext()).inflate(R.layout.left_item_layout, parent, false);

            TextView txtUser = convertView.findViewById(R.id.txtUserLeft);
            TextView txtMessage =  convertView.findViewById(R.id.txtMessageLeft);
            TextView txtTime =   convertView.findViewById(R.id.txtTimeLeft);

            txtUser.setText(message.getSenderName());
            txtMessage.setText(message.getText());
            txtTime.setText(message.getTime());

        }



        return convertView;


    }

    @Override
    public Filter getFilter(){
        return new Filter(){

            @Override
            protected FilterResults performFiltering(CharSequence constraint) {
                constraint = constraint.toString().toLowerCase();
                FilterResults result = new FilterResults();

                if (constraint != null && constraint.toString().length() > 0) {
                    List<Message> founded = new ArrayList<>();
                    for(Message item: origData){
                        if(item.toString().toLowerCase().contains(constraint)){
                            founded.add(item);
                        }
                    }

                    result.values = founded;
                    result.count = founded.size();
                }else {
                    result.values = origData;
                    result.count = origData.size();
                }
                return result;


            }
            @Override
            protected void publishResults(CharSequence constraint, FilterResults results) {
                clear();
                for (Message item : (List<Message>) results.values) {
                    add(item);
                }
                notifyDataSetChanged();

            }

        };
    }



}

工具栏的 XML 文件:

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto">
    <item
        android:id="@+id/symptomSendButton"
        android:icon="@drawable/done_icon"
        android:title="Send"
        app:showAsAction="always"
        app:layout_scrollFlags="scroll|enterAlways|snap"
        android:visible="false" />



    <item
        android:id="@+id/action_search"
        android:icon="@android:drawable/ic_menu_search"
        android:title="Search"
        app:actionViewClass="android.support.v7.widget.SearchView"
        app:showAsAction="ifRoom|collapseActionView" />

</menu>

Answer 1

您使用空列表创建适配器 [因此 origData 是 emply] 并稍后添加不会更新 origData 的项目。所以当你过滤时，列表是空的。

因此你可以尝试2种方法。

方法 1:移动 chatAdapter = new ChatAdapter(getApplicationContext(),fUser,chatLists); chatList.setAdapter(chatAdapter); 获取完整数据列表后进入onDataChange()；

方法 2:覆盖适配器的 add() 和 clear() 方法，因此它们也更新 origData。在过滤器的publishResults()中，将clear()、add(item)改为data.clear() , data.add(item).

希望对您有所帮助!