EventPlugin class Null safety
An EventPlugin receives callbacks when the fields of a GeneratedMessage change.
A GeneratedMessage mixin can install a plugin by overriding the eventPlugin property. The intent is provide mechanism, not policy; each mixin defines its own public API, perhaps using streams.
This is a low-level, synchronous API. Event handlers are called in the middle of protobuf changes. To avoid exposing half-finished changes to user code, plugins should buffer events and send them asynchronously. (See event_mixin.dart for an example.)
GeneratedMessage parent) → void
- Initializes the plugin. [...]
FieldInfo fi) → void
- Called before clearing a field.
FieldInfo fi, dynamic newValue) → void
- Called before setting a field. [...]
Invocation invocation) → dynamic
Invoked when a non-existent method or property is accessed. [...]
) → String
A string representation of this object. [...]