ValueBuilder

Intro

The ValueBuilder extends the StreamBuilder widget providing some callbacks to handle the state of the stream and returning an empty Container if noDataChild is not provided, in order to avoid checking snapshot.hasData.

It takes as a stream parameter an object implementing the StreamedObject interface and triggers the rebuild of the widget whenever the stream emits a new event.

N.B. To use when there is no need to receive a null value.

Usage

ValueBuilder<String>(
  stream: streamedValue,      
  builder: (context, snasphot) => Text(snasphot.data),
  noDataChild: // Widget to show when the stream has no data
  onNoData: () => // or Callback
  errorChild: // Widget to show on error
  onError: (error) => // or Callback
)

If no noDataChild widget or no onNoData callback is provided then an empty Container is returned.

If no errorChild widget or no onError callback is provided then an empty Container is returned.

N.B. The callbacks are executed only if their respective child is not provided.