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我正在尝试创建一个Android应用,我正在使用Firebase存储信息列表。我能够在没有问题的情况下将实时数据库中的信息存储起来,但是我目前遇到的问题是试图找出在添加新内容时如何检索列表。从Firebase获取列表
当我在列表中添加,更改或删除值时,不会调用任何childEventListener
。
FirebaseDatabase database;
DatabaseReference toDatabase;
...
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_world_play_hide);
hideAvatar = (Button) findViewById(R.id.hideAvatar);
database = FirebaseDatabase.getInstance();
toDatabase = database.getReference("jsierra");
...
hideAvatar.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
...
getCurrentLocation();
currentCoordinates = new LatLng(latitude, longitude);
data store = new data(currentCoordinates);
toDatabase.push().setValue(store);
map.addMarker(new MarkerOptions().position(currentCoordinates));
}
});
}
protected void onStart() {
apiClient.connect();
super.onStart();
DatabaseReference test = toDatabase.child("jsierra");
test.addChildEventListener(new ChildEventListener() {
@Override
public void onChildAdded(DataSnapshot dataSnapshot, String s) {
Toast.makeText(getBaseContext(), "Child Added", Toast.LENGTH_LONG).show();
givenData = dataSnapshot.getValue(data.class);
}
@Override
public void onChildChanged(DataSnapshot dataSnapshot, String s) {
givenData = dataSnapshot.getValue(data.class);
Toast.makeText(getBaseContext(), "Child Changed", Toast.LENGTH_LONG).show();
}
@Override
public void onChildRemoved(DataSnapshot dataSnapshot) {
givenData = dataSnapshot.getValue(data.class);
Toast.makeText(getBaseContext(), "Child Removed", Toast.LENGTH_LONG).show();
}
@Override
public void onChildMoved(DataSnapshot dataSnapshot, String s) {
givenData = dataSnapshot.getValue(data.class);
Toast.makeText(getBaseContext(), "Child Moved", Toast.LENGTH_LONG).show();
}
@Override
public void onCancelled(DatabaseError databaseError) {
Toast.makeText(getBaseContext(), "Failed", Toast.LENGTH_LONG).show();
}
});
}
我改变了它,并得到一个错误 “无法解析法儿”。我查看了FirebaseDatabase API,但子项不在其中。我试过getReference,它工作!谢谢您的帮助! –
@JuanSierra:你说得对。我修好了它。 –