Firebase 'child_removed' event listener not working

Question

'child_added' works fine, but 'child_removed' does not work.

The data index is ".indexOn": "status".

• Firebase data

  {
      "user uid" : {
          "-Kb8FSBMOvcposJ-iJYL" : {
              "createDate" : 1485140252291,
              "message" : "login",
              "response" : "none",
              "status" : "0",
              "title" : "8. sign-in"
          },
         "-KbL6d1xrfqCBAcP7_Qu" : {
              "createDate" : 1485356045006,
              "message" : "logout",
              "response" : "none",
              "status" : "1",
              "title" : "sign-out"
          }
      }
  }
  

• Firebase event listener

  var notiRef = firebase.database().ref('message/' + user.uid);
  notiRef.orderByChild('status').equalTo('wait').on('child_added', function(snapshot) {
      //do something...
  });
  
  notiRef.orderByChild('status').equalTo('wait').on('child_moved', function(snapshot) {
      // not worked.
  });
  
  firebase.database().ref('notification/' + user.uid + '/uid').on('child_moved', function(snapshot) {
      // not worked.
  });
  notiRef.on('child_moved', function(snapshot) {
      // not worked.
  });
  

All three 'child_removed' in the above code will not work. Is it a problem to set the ref target? Or is it a problem with setting indexOn? (Setting indexOn is required)

Answer 1

Do you mean that child_moved events are not fired? Because that is what you are listening for.

If it is removal of children you are interested, try listening for child_removed instead of child_moved.

Ex:

notiRef.on('child_removed', function(snapshot) {
      // probably will work.
});