flutter开发实战-Camera自定义相机拍照功能实现

import 'package:flutter/material.dart';
import 'package:camera/camera.dart';
 
class CameraApp extends StatefulWidget {
  @override
  _CameraAppState createState() => _CameraAppState();
}
 
class _CameraAppState extends State<CameraApp> {
  CameraController _controller;
  Future<void> _initializeControllerFuture;
 
  @override
  void initState() {
    super.initState();
    _controller = CameraController(cameras[0], ResolutionPreset.medium);
    _initializeControllerFuture = _controller.initialize();
  }
 
  @override
  void dispose() {
    _controller.dispose();
    super.dispose();
  }
 
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: FutureBuilder<void>(
        future: _initializeControllerFuture,
        builder: (context, snapshot) {
          if (snapshot.connectionState == ConnectionState.done) {
            return CameraPreview(_controller);
          } else {
            return Center(child: CircularProgressIndicator());
          }
        },
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: () async {
          try {
            await _initializeControllerFuture;
            final path = join(
              (await getApplicationDocumentsDirectory()).path,
              '${DateTime.now()}.png',
            );
            await _controller.takePicture(path);
          } catch (e) {
            print(e);
          }
        },
        child: Icon(Icons.camera_alt),
      ),
    );
  }
}

这段代码实现了一个简单的相机预览界面，并在底部浮动按钮点击时触发拍照功能。它展示了如何使用Flutter的camera插件来初始化相机控制器，预览相机画面，并在用户点击拍照按钮时保存一张照片到设备文件系统。