This is a Rust version of MMKV.

By default, this lib uses CRC8 to check data integrity.

If include feature encryption, this lib will encrypt the data with AES-EAX.

MMKV is thread-safe but cannot guarantee cross-process data consistency. If you want to use it in a cross-process scenario, please ensure that there is no competing write.

Add dependency:

cargo add mmkv

And use MMKV directly:

use mmkv::{LogLevel, MMKV};

fn main() {
    // Set the log level of the library
    MMKV::set_log_level(LogLevel::Verbose);
    let temp_dir = std::env::temp_dir();
    let dir = temp_dir.join("test1");
    let _ = std::fs::create_dir(&dir);
    // Initialize it with a directory, the library will crate a file,
    // named "mini_mmkv" under this dir.
    let mmkv = MMKV::new(dir.to_str().unwrap());
    // Put and get result, for most case should be Ok(()),
    // if something wrong, it contains the useful info.
    let ret = mmkv.put_i32("key1", 1);
    println!("{:?}", ret); // Ok(())
    // Get result with key
    println!("{:?}", mmkv.get_i32("key1")); // Ok(1)
    // Put and unwrap the result
    mmkv.put_str("key1", "value").unwrap();
    println!("{:?}", mmkv.get_i32("key1")); // Err(TypeMissMatch)
    println!("{:?}", mmkv.get_str("key1")); // Ok("value")

    let dir = temp_dir.join("test2");
    let _ = std::fs::create_dir(&dir);
    // Create another instance with different path
    let new_mmkv = MMKV::new(dir.to_str().unwrap());
    new_mmkv.put_bool("key1", true).unwrap();
    println!("{:?}", new_mmkv.get_bool("key1")); // Ok(true)
    // clear all data to free disk space
    new_mmkv.clear_data();
}

Add dependency:

cargo add mmkv --features encryption

Then init MMKV with an encryption credential:

let mmkv = MMKV::new(".", "88C51C536176AD8A8EE4A06F62EE897E")

Encryption will greatly reduce the efficiency of reading and writing, and will also increase the file size, use at your own risk!

Add lib dependency to gradle:

dependencies {
    implementation("net.yangkx:mmkv:0.4.0")
    // Or another one with encryption feature
    // implementation("net.yangkx:mmkv-encrypt:0.4.0")
}

You can find all versions in the Releases.

Use the kotlin API:

class MyApplication : Application() {

    companion object {
        lateinit var mmkv: MMKV
    }

    override fun onCreate() {
        super.onCreate()
        MMKV.setLogLevel(LogLevel.VERBOSE)
        val dir = this.getDir("mmkv", Context.MODE_PRIVATE)
        mmkv = MMKV(dir.absolutePath)
        // If you are using mmkv with encryption
        // mmkv = MMKV(dir.absolutePath, "88C51C536176AD8A8EE4A06F62EE897E")
    }
}

class MainActivity : AppCompatActivity() {

    private val mmkv: MMKV
        get() = MyApplication.mmkv

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        binding = ActivityMainBinding.inflate(layoutInflater)
        setContentView(binding.root)
        mmkv.putString("first_key", "first value")
        mmkv.putInt("second_key", 1024)
        mmkv.putBool("third_key", true)
        binding.string.text = mmkv.getString("first_key", "default")
        binding.integer.text = mmkv.getInt("second_key", 0).toString()
        binding.bool.text = mmkv.getBool("third_key", false).toString()
    }
}

Check the android demo for more detail.

1. Add this repo as swift package dependency to your Xcode project.

2. Init MMKV instance before use the API, for example:

   import Foundation
   import MMKV
   
   class MMKVManager {
       static var inst = initMMKV()
   }
   
   func initMMKV() -> MMKV {
       let paths = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)
       let documentsDirectory = paths[0]
       let docURL = URL(string: documentsDirectory)!
       let dataPath = docURL.appendingPathComponent("mmkv")
       if !FileManager.default.fileExists(atPath: dataPath.path) {
           do {
               try FileManager.default.createDirectory(atPath: dataPath.path, withIntermediateDirectories: true, attributes: nil)
           } catch {
               print(error.localizedDescription)
           }
       }
       return MMKV(dataPath.path)
   }

3. Use MMKV.shared to access API directly:

   import SwiftUI
   import MMKV
   
   struct ContentView: View {
       @State var textContent: String = "Hello, world!"
       var body: some View {
           Text(textContent)
               .onTapGesture {
                   let value = MMKVManager.inst.getInt32(key: "int_key").unwrap(defalutValue: 0)
                   MMKVManager.inst.putInt32(key: "int_key", value: value + 1).unwrap(defalutValue: ())
                   textContent = MMKVManager.inst.getInt32(key: "int_key").unwrap(defalutValue: 0).formatted()
               }
       }
   }

Check the ios demo for more detail.