ValueEventListener
public interfaceValueEventListener
Classes implementing this interface can be used to receive events about data changes at a location. Attach the listener to a location useraddValueEventListener.
Summary
Public methods | |
|---|---|
abstract void | onCancelled(@NonNullDatabaseError error)This method will be triggered in the event that this listener either failed at the server, or is removed as a result of the security and Firebase Database rules. |
abstract void | onDataChange(@NonNullDataSnapshot snapshot)This method will be called with a snapshot of the data at this location. |
Public methods
onCancelled
abstract void onCancelled(@NonNullDatabaseError error)
This method will be triggered in the event that this listener either failed at the server, or is removed as a result of the security and Firebase Database rules. For more information on securing your data, see: Security Quickstart
| Parameters | |
|---|---|
@NonNullDatabaseError error | A description of the error that occurred |
onDataChange
abstract void onDataChange(@NonNullDataSnapshot snapshot)
This method will be called with a snapshot of the data at this location. It will also be called each time that data changes.
| Parameters | |
|---|---|
@NonNullDataSnapshot snapshot | The current data at the location |
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Last updated 2025-07-21 UTC.