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Live Cells

A simple yet powerful reactive programming library

Reactive Programming

A reactive programming library for Dart and Flutter
Define cells for your data
Declare observers on cells
Observers are called automatically when cell values change

// Define a cell
final count = MutableCell(0);

// Define an observer
ValueCell.watch(() {
  print('${count()}');
});

// Increment cell value
// Automatically calls observer
count.value++;

Benefits over ValueNotifier

final a = MutableCell(0);
final b = MutableCell(1);

final sum = a + b;

Cells can be defined as an expression of other cells
No need to add and remove listeners
Simpler resource management
Disposed automatically

Two-way data flow

final n = MutableCell(0);
final strN = n.mutableString();

n.value = 5;
print(strN.value); // '5'

strN.value = '10';
print(n.value); // 10

Data can flow in both directions
Most other libraries (if not all) are limited to unidirectional data flow

Simple and Unobtrusive

You only need to learn one basic building block — the cell

Cells are designed to be indistinguishable from the values they hold

// A list cell
ValueCell<List> list;

// A cell for the index
ValueCell<int> index

// A cell which access a list item
final e = list[index];

No need to implement complicated notifier or state classes.

Bind Data to Widgets

Integrated with a widget library
Allows widget properties to be bound directly to cells
Reduces the need for controller objects and event handlers
Only rebuild the widgets that have actually changed

final content = MutableCell('');
...
Column(
  children: [
    // Cell content bound to TextField content
    LiveTextField(
      content: content
    ),
    CellWidget.builder((_) =>
       Text('You wrote: ${content()}')
    )
  ]
)