watch method

void watch(
  1. VoidCallback watch
)

Register a callback to be called whenever the values of cells change.

The function watch is called whenever the values of the cells referenced within it using ValueCell.call change. watch is called once after it is registered.

watch is not called after the widget is removed from the tree.

NOTE: The callback is only registered once during the first build, and will not be registered again on subsequent builds.

NOTE: This method may only be called within the build method.

Implementation

void watch(VoidCallback watch) {
  assert(_activeCellElement != null);
  _activeCellElement!.getWatcher(watch);
}