dartnative_hive

Hive for DartNative — a fast, pure-Dart key–value database with a one-line native init. Same API on iOS and Android.

Why you'll like it

• Pure-Dart speed — Hive (community edition), no platform channels.
• One-line init — Hive.initDartNative(docsDir) and you're set.
• The full Hive API — the code of hive_ce 2.20.1, ported into this package and behaving the same: boxes, type adapters, lazy boxes, keys in sorted order, box events. hive_ce's own tests pass on it.
• Fast, safe writes — boxes are stored in memory-mapped files, a mechanism built into iOS and Android. A put hands the value to the operating system before it returns, so nothing is lost if the app crashes or is killed.

Highlights

• Hive.initDartNative(docsDirPath, {subDir, mmap}) — point Hive at a storage directory.
• Hive.openBox(name) + box.put / box.get / box.delete — the usual Hive API.

Install

dependencies:
  dartnative_hive: ^2.0.0   # from dartpub.dev

dn pub get

Quick look

import 'package:dartnative_hive/dartnative_hive.dart';

// Point Hive at your app's documents directory, once at startup
// (getApplicationDocumentsDirectory() from dartnative_path_provider):
Hive.initDartNative(documentsPath);

final box = await Hive.openBox('settings');
await box.put('theme', 'dark');
final theme = box.get('theme'); // 'dark'

Type adapters

To store your own classes and enums, generate their adapters with dartnative_hive_generator:

dev_dependencies:
  dartnative_hive_generator:
    hosted: https://dartpub.dev
    version: ^2.0.0
  build_runner: ^2.5.4

dn pub run build_runner build

Its README shows the annotations. Adapters written by hand work as they do in any Hive app.

Platform setup

iOS

No native setup required.

Android

No native setup required.

Fast, safe writes

Boxes are stored in memory-mapped files, a mechanism built into iOS and Android: the file's contents sit in memory that belongs to the operating system, not to the app, and the system writes them to storage itself. A put copies the value there before it returns, even if its future is never awaited. From that moment the value is safe: nothing is lost if the app crashes, is closed from the app switcher, or is stopped by the system. A small value takes under a microsecond.

The one event the system cannot cover is a sudden loss of power before it has written the data to storage, which can lose the latest writes of any app that writes files. When a value must survive even that, await box.flush(): it returns once the data is on the device's storage.

Reads are a lookup in memory.

On hive_ce's own benchmark, 1,000 awaited box.add calls of a ten-field object take 1.61 ms on an iPhone 16 Pro, against 22.8 ms for hive_ce in a Flutter app on the same phone; 100,000 take 0.17 s against 2.34 s.

Writes and reads of a short string, on 1 key and on 1000 keys, on the same phone:

A mid-range Android phone shows gains of the same size, measured against hive_ce's own file storage on that phone: 16 to 97 times faster on hive_ce's benchmark, and 23 to 49 times faster on awaited writes of a short string.

The example's benchmarks/ folder has every number and how it was measured.

To use hive_ce's own file storage instead, where a put is safe once its future completes, pass mmap: false:

Hive.initDartNative(documentsPath, mmap: false);

The file format is the same either way, so existing boxes open in both modes. The example's Benchmark screen times writes and reads in both modes on your own device.

Example

The example/ app opens a box and round-trips a value, and its Benchmark screen times every kind of write and read in both modes — borrow from it freely.

Run it:

cd example
dn pub get
dn run -d <device-id>

The example is an official demo: free to run, no license setup. Always use dn (not the underlying SDK CLI) for run/build/pub commands.

Credits & license

Built on the source of hive_ce, the community edition of Hive, ported into this package; its licence is in THIRD_PARTY_NOTICES.

First-party DartNative plugin, free to use in any DartNative app. Distributed through dartpub.dev; report issues on the plugin's page.