Firebase android studio从FirebaseListAdapter中移除项目 [英] Firebase android studio remove item from FirebaseListAdapter

问题描述

首先，我想为我可怜的英语道歉。

我刚开始使用android studio进行冒险，接下来是一些教程，我对其中的一个问题有疑问。我在许多地方寻找这个答案，但我发现没有满足我的需要。

我创建了一个聊天应用程序与Android作为后端数据库的FIREBASE，但我会喜欢添加一些额外的功能。即将删除项目。

我会在这里发布我的代码，有人可以告诉我如何删除从FirebaseListAdapter中按下的项目。
$ b $ MainActivity：

pre $ public class MainActivity extends ListActivity {
private Firebase mFirebaseRef;
FirebaseListAdapter< ChatMessage> mListAdapter;

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


Firebase.getDefaultConfig（）。setPersistenceEnabled（true）;
Firebase.setAndroidContext（this）;

mFirebaseRef =新的Firebase（https://shining-heat-1471.firebaseio.com）;


final EditText textEdit =（EditText）this.findViewById（R.id.text_edit）;
按钮sendButton =（Button）this.findViewById（R.id.send_button）;

sendButton.setOnClickListener（new View.OnClickListener（）{
@Override $ b $ public void onClick（View v）{
String text = textEdit.getText（）。 toString（）;
ChatMessage message = new ChatMessage（Android User，text）;
mFirebaseRef.push（）。setValue（message）; $ b $ textEdit.setText（）;
}
}）;

$ b mListAdapter = new FirebaseListAdapter< ChatMessage>（this，ChatMessage.class，
android.R.layout.two_line_list_item，mFirebaseRef）{
@Override
protected void populateView（View v，ChatMessage model）{
（（TextView）v.findViewById（android.R.id.text1））。setText（model.getName（））;
（（TextView）v.findViewById（android.R.id.text2））。setText（model.getText（））;
}
};
setListAdapter（mListAdapter）;


@Override
protected void onDestroy（）{
super.onDestroy（）;
mListAdapter.cleanup（）;

$ / code>

ChatMessage：



  public class ChatMessage {
 private String name; 
私人字符串文本; 
 $ b公共ChatMessage（）{
 // Firebase的反序列化程序所必需的
} 
 public ChatMessage（String name，String text）{
 this.name =名称; 
 this.text = text; 
} 
 
 public String getName（）{return name; } 
 
 public String getText（）{return text; } 
} 
  




解决方案

找出用户点击的项目（但此可能是一个好开始）。



一旦您知道用户点击的项目的位置，您可以轻松地将其从Firebase中移除：

  Firebase itemRef = adapter.getRef（position）; 
 itemRef.removeValue（）; 
  

这将从列表适配器的数据库和中移除项目。


Firstly I would like to apologize for my poor English.

I just started my adventure with android studio and followed some tutorials and I have a question about one of them. I was looking in many places for this answer but I found none that would satisfy my needs.

I created a chat app in android studio with FIREBASE as backend database but I would like to add some extra functionality to it. Namely remove item.

I’ll post my code here, can someone tell me how can I make it possible to delete Item that I pressed on from the FirebaseListAdapter.

MainActivity:

public class MainActivity extends ListActivity {
private Firebase mFirebaseRef;
FirebaseListAdapter<ChatMessage> mListAdapter;

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


    Firebase.getDefaultConfig().setPersistenceEnabled(true);
    Firebase.setAndroidContext(this);

    mFirebaseRef = new Firebase("https://shining-heat-1471.firebaseio.com");


    final EditText textEdit = (EditText) this.findViewById(R.id.text_edit);
    Button sendButton = (Button) this.findViewById(R.id.send_button);

    sendButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            String text = textEdit.getText().toString();
            ChatMessage message = new ChatMessage("Android User", text);
            mFirebaseRef.push().setValue(message);
            textEdit.setText("");
        }
    });


    mListAdapter = new FirebaseListAdapter<ChatMessage>(this, ChatMessage.class,
            android.R.layout.two_line_list_item, mFirebaseRef) {
        @Override
        protected void populateView(View v, ChatMessage model) {
            ((TextView)v.findViewById(android.R.id.text1)).setText(model.getName());
            ((TextView)v.findViewById(android.R.id.text2)).setText(model.getText());
        }
    };
    setListAdapter(mListAdapter);
}

@Override
protected void onDestroy() {
    super.onDestroy();
    mListAdapter.cleanup();
}

ChatMessage:

public class ChatMessage {
private String name;
private String text;

public ChatMessage() {
    // necessary for Firebase's deserializer
}
public ChatMessage(String name, String text) {
    this.name = name;
    this.text = text;
}

public String getName() { return name; }

public String getText() { return text; }
}

解决方案

I'll leave it to you to figure out what item the user clicked on (but this might be a good start).

Once you know the position of the item the user clicked on, you can remove it from Firebase easily with:

Firebase itemRef = adapter.getRef(position);
itemRef.removeValue();

This will remove the item from the database and from the list adapter.

这篇关于Firebase android studio从FirebaseListAdapter中移除项目的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！