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Write iOS&macOS&Android Code using Dart. This package liberates you from redundant glue code and low performance of Flutter Channel.


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DartNative operates as a bridge to communicate between Dart and native APIs.

Replaces the low-performing Flutter channel with faster and more concise code.

pub package Build Status Dart CI


Dynamic synchronous & asynchronous channeling

DartNative calls any native API dynamically. It supports both synchronous and asynchronous channeling.

Direct call between multi-language interfaces

Serialization of parameters and return values like Flutter Channel is no longer required. DartNative provides direct calls and automatic object marshalling between language interfaces.

Dart finalizer

Dart finalizer is only supported above Flutter 3(Dart 2.17), but with DartNative it is available in Dart Flutter 2.2.0(Dart 2.13.0) and up.

Autogenerate succinct bridging code

DartNative supports automatic type conversion so its bridging code is shorter & simpler than the Flutter channel.

The design and vision of this package:


DartNative Version Flutter Requirements Codegen Version
0.4.x - 0.7.x Flutter 2.2.0 (Dart 2.13.0) 2.x
0.3.x Flutter 1.20.0 (Dart 2.9.1) 1.2.x
0.2.x Flutter 1.12.13 (Dart 2.7) 1.x

Supported Platforms

iOS & macOS & Android


Basic usage: Interface binding

Add dart_native to dependencies and build_runner to dev_dependencies. Then you can write code. Here are some examples:

Dart calls Native

Dart code:

final interface = Interface("MyFirstInterface");
// Example for string type.
String helloWorld() {
    return interface.invokeMethodSync('hello', args: ['world']);
// Example for num type.
Future<int> sum(int a, int b) {
    return interface.invokeMethod('sum', args: [a, b]);

Corresponding Objective-C code:

@implementation DNInterfaceDemo

// Register interface name.

// Register method "hello".
InterfaceMethod(hello, myHello:(NSString *)str) {
    return [NSString stringWithFormat:@"hello %@!", str];

// Register method "sum".
InterfaceMethod(sum, addA:(int32_t)a withB:(int32_t)b) {
    return @(a + b);


Corresponding Java code:

// load

@InterfaceEntry(name = "MyFirstInterface")
public class InterfaceDemo extends DartNativeInterface {

    @InterfaceMethod(name = "hello")
    public String hello(String str) {
        return "hello " + str;

    @InterfaceMethod(name = "sum")
    public int sum(int a, int b) {
        return a + b;

NOTE: If your so path is custom, you need pass specific path.


And before using DartNative in dart, first invoke dartNativeInitCustomSoPath(). It will get path from channel.

Native calls Dart

Dart code:

        (double unitCost, int count, List list) async {
    return {'totalCost: ${unitCost * count}': list};

Corresponding Objective-C code:

[self invokeMethod:@"totalCost"
         arguments:@[@0.123456789, @10, @[@"testArray"]]
            result:^(id _Nullable result, NSError * _Nullable error) {
    NSLog(@"%@", result);

Corresponding Java code:

invokeMethod("totalCost", new Object[]{0.123456789, 10, Arrays.asList("hello", "world")},
             new DartNativeResult() {
                public void onResult(@Nullable Object result) {
                    Map retMap = (Map) result;
                    // do something

                public void error(@Nullable String errorMessage) {
                    // do something

Dart finalizer

final foo = Bar(); // A custom instance.
unitTest.addFinalizer(() { // register a finalizer callback.
  print('The instance of \'foo\' has been destroyed!'); // When `foo` is destroyed by GC, this line of code will be executed.

Data types support

Dart Objective-C Swift Java
null nil nil null
bool BOOL Bool bool
int NSInteger Int int
double double Double double
String NSString String String
List NSArray Array List, ArrayList
Map NSDictionary Dictionary Map, HashMap
Set NSSet Set Set, HashSet
Function Block Closure Promise
Pointer void * UnsafeMutableRawPointer -
NativeByte NSData Data DirectByteBuffer
NativeObject NSObject NSObject Object

Advanced usage: Invoke methods dynamically

  • Step 1: Add dart_native to dependencies and build_runner to dev_dependencies.

  • Step 2: Generate Dart wrapper code with @dartnative/codegen or write Dart code manually.

  • Step 3: Generate code for automatic type conversion using dart_native_gen with the following steps (3.1-3.3):

    • 3.1 Annotate a Dart wrapper class with @native.

      class RuntimeSon extends RuntimeStub {
        RuntimeSon([Class isa]) : super(Class('RuntimeSon'));
        RuntimeSon.fromPointer(Pointer<Void> ptr) : super.fromPointer(ptr);
    • 3.2 Annotate your own entry (such asmain()) with @nativeRoot.

      void main() {
    • 3.3 Run

      flutter packages pub run build_runner build --delete-conflicting-outputs 

      to generate files into your source directory.

      Note: we recommend running clean first:

      flutter packages pub run build_runner clean
  • Step 4: Call autogenerated function in <generated-name>.dn.dart in 3.3. The function name is determined by name in pubspec.yaml.

    void main() {
      // Function name is generated by name in pubspec.yaml.
  • Step 5: Then you can write code. Here are some examples:

    • 5.1 iOS:

      Dart code (generated):

      // new Objective-C object.
      RuntimeStub stub = RuntimeStub();
      // Dart function will be converted to Objective-C block.
      stub.fooBlock((NSObject a) {
          print('hello block! ${a.toString()}');
          return 101;
      // support built-in structs.
      CGRect rect = stub.fooCGRect(CGRect(4, 3, 2, 1));

      Corresponding Objective-C code:

      typedef int(^BarBlock)(NSObject *a);
      @interface RuntimeStub
      - (CGRect)fooCGRect:(CGRect)rect;
      - (void)fooBlock:(BarBlock)block;

      More iOS examples see: ios_unit_test.dart

    • 5.2 Android:

      Dart code (generated):

      // new Java object.
      RuntimeStub stub = RuntimeStub();
      // get java list.
      List list = stub.getList([1, 2, 3, 4]);
      // support interface.

      Corresponding Java code:

      public class RuntimeStub {
          public List<Integer> getList(List<Integer> list) {
              List<Integer> returnList = new ArrayList<>();
              return returnList;
          public void setDelegateListener(SampleDelegate delegate) {

      More android examples see: android_unit_test.dart

NOTE: If you use dart_native on macOS, you must use use_frameworks! in your Podfile.


Further reading


Q: Failed to lookup symbol (dlsym(RTLD_DEFAULT, InitDartApiDL): symbol not found) on macOS archive.

A: Select one solution:

  1. Use dynamic library: Add use_frameworks! in Podfile.
  2. Select Target Runner -> Build Settings -> Strip Style -> change from "All Symbols" to "Non-Global Symbols"


  • If you need help or you'd like to ask a general question, open an issue.
  • If you found a bug, open an issue.
  • If you have a feature request, open an issue.
  • If you want to contribute, submit a pull request.


DartNative is available under the BSD 3-Clause License. See the LICENSE file for more info.