flutter_ali_camera/lib/camera_view_controller.dart

import 'dart:async';

import 'package:flutter/cupertino.dart';
import 'package:flutter/services.dart';

import 'camera_option.dart';

class CameraViewController {
  MethodChannel _methodChannel;
  final StreamController<Map> _recordController = StreamController.broadcast();

  Stream<Map> get recordUpdate => _recordController.stream;

  CameraViewController({@required int id}) {
    _methodChannel = MethodChannel("com.i2edu.cameraLib/camera_view_$id");
    _methodChannel.setMethodCallHandler(_onMethodCallHandler);
  }

  Future<void> create({@required CameraRecordOption recordOption}) async {
    return _methodChannel.invokeMethod("create", {"recordOption": recordOption.toMap()});
  }

  Future<void> startPreview() {
    return _methodChannel.invokeMethod("startPreview");
  }

  Future<void> stopPreview() {
    return _methodChannel.invokeMethod("stopPreview");
  }

  Future<void> switchCamera() {
    return _methodChannel.invokeMethod("switchCamera");
  }

  Future<void> setBeauty(int level) {
    return _methodChannel.invokeMethod("setBeauty", {"level": level});
  }

  Future<void> setFilter(String path) {
    return _methodChannel.invokeMethod("setFilter", {"path": path});
  }

  Future<void> startRecord(int max, String recordPath) {
    return _methodChannel.invokeMethod("startRecord", {"max": max, "recordPath": recordPath});
  }

  Future<bool> startCompose(String outputPath, String bgmPath,
      List<String> paths, List<int> durations, CameraComposeOption option) {
    if (paths.length != durations.length) {
      print("error: length error");
      return null;
    }
    return _methodChannel.invokeMethod("startCompose", {
      "outputPath": outputPath,
      "bgmPath": bgmPath,
      "paths": paths,
      "durations": durations,
      "composeOption": option.toMap()
    });
  }

  void dispose() async {
    if (!_recordController.isClosed) {
      _recordController.close();
    }
  }

  Future _onMethodCallHandler(MethodCall call) {
    switch (call.method) {
      case "recordUpdate":
        _recordController.add(call.arguments);
        break;
    }
    return null;
  }
}