persist_notifier 1.0.1

A ValueNotifier designed for defining settings and providing a solution with a default value and notification system.

Persist Notifier plugin

Wraps platform-specific persistent storage for simple data (NSUserDefaults on iOS and macOS, SharedPreferences on Android, etc.) using existing ValueNotifier methods and newly defined methods for additional functionality. Data may be persisted to disk asynchronously or synchronously.

Supported data types are int, double, bool, String and List<String>.

For information on storage of the values, see the documentation on SharedPreferences.

Usage

To use this plugin, add persist_notifier as a dependency in your pubspec.yaml file.

Examples

Here are small examples that show you how to use the API.

Definition

// Define as static or member variable
PersistNotifier pn = PersistNotifier("com.example.test", 0);

void example() async {
    // Define async
    var pn = PersistNotifier("com.example.test", 0);
    // Define sync
    var pn = await PersistNotifier.create("com.example.test", 0);
}

Read data

// Read in the default or stored value
PersistNotifier pn = await PersistNotifier.create("com.example.test", 0);
final int counter = pn.value;

// Force a sync of the stored value if the underlying value has changed
pn.resync();

Write data

// Read in the default or stored value
PersistNotifier pn = await PersistNotifier.create("com.example.test", 0);
pn.value = 7; // Async storage update
bool success = await pn.set(7); // Sync storage update

Remove an entry

// Reset the value back to the default
PersistNotifier pn = await PersistNotifier.create("com.example.test", 0);
pn.value = 7;
pn.reset();
// pn.value == 0

Storage location by platform

Platform	Location
Android	SharedPreferences
iOS	NSUserDefaults
Linux	In the XDG_DATA_HOME directory
macOS	NSUserDefaults
Web	LocalStorage
Windows	In the roaming AppData directory