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Java 如何检索android的firebase数据_Java_Android_Listview_Firebase_Firebase Realtime Database - Fatal编程技术网

Java 如何检索android的firebase数据

Java 如何检索android的firebase数据,java,android,listview,firebase,firebase-realtime-database,Java,Android,Listview,Firebase,Firebase Realtime Database,我使用Firebase开发我的应用程序。现在我的查询是我从Firebase中找到数据,但没有在我的对象上设置它我的Firebase数据结构如下图所示 我的代码是 mRef.addValueEventListener(new ValueEventListener() { @Override public void onDataChange(DataSnapshot dataSnapshot) { adapter=new LiveNewsA

我使用Firebase开发我的应用程序。现在我的查询是我从Firebase中找到数据,但没有在我的对象上设置它我的Firebase数据结构如下图所示

我的代码是

mRef.addValueEventListener(new ValueEventListener() {
        @Override
        public void onDataChange(DataSnapshot dataSnapshot) {

            adapter=new LiveNewsAdapter(dataSnapshot);
            newsList.setAdapter(adapter);

        }

        @Override
        public void onCancelled(DatabaseError databaseError) {

        }
    });
我的适配器类是

public class LiveNewsAdapter extends RecyclerView.Adapter<LiveNewsAdapter.ViewHolder> {
private DataSnapshot mDataset;


public static class ViewHolder extends RecyclerView.ViewHolder {

    public TextView mTextView;

   public ViewHolder(View v) {
        super(v);
       mTextView=(TextView) v.findViewById(R.id.tvNewsView);
    }
}

// Provide a suitable constructor (depends on the kind of dataset)
public LiveNewsAdapter(DataSnapshot myDataset) {
    mDataset = myDataset;
}

// Create new views (invoked by the layout manager)
@Override
public LiveNewsAdapter.ViewHolder onCreateViewHolder(ViewGroup parent,
                                               int viewType) {
    // create a new view
    View v = LayoutInflater.from(parent.getContext())
            .inflate(R.layout.text_livenews, parent, false);
    // set the view's size, margins, paddings and layout parameters

    ViewHolder vh = new ViewHolder(v);
    return vh;
}

// Replace the contents of a view (invoked by the layout manager)
@Override
public void onBindViewHolder(ViewHolder holder, int position) {
    // - get element from your dataset at this position
    // - replace the contents of the view with that element
    System.out.println("DARA  "+ mDataset.getValue());




    for (DataSnapshot messageSnapshot: mDataset.getChildren()) {
        String name = (String) messageSnapshot.child("Divya Bhaskar").getValue();
        String message = (String) messageSnapshot.child("Sandesh").getValue();

        System.out.println("NMAE  : "+name);
    }

}

// Return the size of your dataset (invoked by the layout manager)
@Override
public int getItemCount() {
    return (int) mDataset.getChildrenCount();
}
公共类LiveNewsAdapter扩展了RecyclerView.Adapter{ 私有数据集; 公共静态类ViewHolder扩展了RecyclerView.ViewHolder{ 公共文本视图mTextView; 公共视图持有者(视图v){ 超级(五); mTextView=(TextView)v.findViewById(R.id.tvNewsView); } } //提供合适的构造函数(取决于数据集的类型) 公共LiveNewsAdapter(DataSnapshot myDataset){ mDataset=myDataset; } //创建新视图(由布局管理器调用) @凌驾 public LiveNewsAdapter.ViewHolder onCreateViewHolder(视图组父级、, int视图类型){ //创建新视图 视图v=LayoutInflater.from(parent.getContext()) .充气(R.layout.text_livenews,父项,false); //设置视图的大小、边距、填充和布局参数 视窗支架vh=新视窗支架(v); 返回vh; } //替换视图的内容(由布局管理器调用) @凌驾 公共无效onBindViewHolder(ViewHolder,int位置){ //-在此位置从数据集中获取元素 //-用该元素替换视图的内容 System.out.println(“DARA”+mDataset.getValue()); 对于(DataSnapshot messageSnapshot:mDataset.getChildren()){ 字符串名称=(字符串)messageSnapshot.child(“Divya Bhaskar”).getValue(); String message=(String)messageSnapshot.child(“Sandesh”).getValue(); System.out.println(“NMAE:+名称); } } //返回数据集的大小(由布局管理器调用) @凌驾 public int getItemCount(){ 返回(int)mDataset.getChildrenCount(); } }

请帮助我了解如何在
TextView