Java 如何检索android的firebase数据
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
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