ImageProcess/native_vision/example/lib/doc_crop_page.dart

import 'dart:io';

import 'package:flutter/material.dart';
import 'package:image_size_getter/file_input.dart';
import 'package:image_size_getter/image_size_getter.dart';
import 'package:native_vision/edge_detection.dart';
import 'package:native_vision/widget/edge_detection_shape.dart';
import 'dart:ui' as ui;
import 'package:native_vision/native/doc_cropper.dart';
import 'package:native_vision_example/doc_clean_page.dart';

import 'loading_overlay.dart';

class DocCropPage extends StatefulWidget {
  final String imgPath;
  final EdgeDetectionResult edgeDetectionResult;
  const DocCropPage(
      {Key? key, required this.imgPath, required this.edgeDetectionResult})
      : super(key: key);

  @override
  State<StatefulWidget> createState() {
    return DocCropPageState();
  }
}

class DocCropPageState extends State<DocCropPage> {
  GlobalKey imageWidgetKey = GlobalKey();

  Future<Map<String, ui.Size>> calculateImgSize() async {
    final screenSize = MediaQuery.of(context).size;

    final imgSize = ImageSizeGetter.getSize(FileInput(File(widget.imgPath)));
    final double width, height;
    if (imgSize.needRotate) {
      width = imgSize.height.toDouble();
      height = imgSize.width.toDouble();
    } else {
      width = imgSize.width.toDouble();
      height = imgSize.height.toDouble();
    }
    final aspectRatio = width / height;
    final imgW = screenSize.width;
    final imgH = imgW / aspectRatio;
    return {
      "renderedImageSize": ui.Size(imgW, imgH),
      "originalImageSize": ui.Size(width, height)
    };
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text("裁剪")),
      body: Stack(children: [
        FutureBuilder<Map<String, ui.Size>>(
            future: calculateImgSize(),
            builder: (context, snapshot) {
              final data = snapshot.data;
              if (data != null) {
                final renderedImageSize = data["renderedImageSize"];
                final originalImageSize = data["originalImageSize"];
                return Container(
                  alignment: Alignment.center,
                  color: Colors.blue,
                  child: Stack(
                    children: [
                      Image.file(
                        File(widget.imgPath),
                        key: imageWidgetKey,
                        width: renderedImageSize!.width,
                        height: renderedImageSize.height,
                        cacheHeight: (renderedImageSize.height *
                                MediaQuery.of(context).devicePixelRatio)
                            .toInt(),
                        cacheWidth: (renderedImageSize.width *
                                MediaQuery.of(context).devicePixelRatio)
                            .toInt(),
                      ),
                      SizedBox(
                        width: renderedImageSize.width,
                        height: renderedImageSize.height,
                        child: EdgeDetectionShape(
                            renderedImageSize: renderedImageSize,
                            originalImageSize: originalImageSize!,
                            edgeDetectionResult: widget.edgeDetectionResult),
                      )
                    ],
                  ),
                );
              }
              return Container();
            }),
        Positioned(
          bottom: 20,
          left: 0,
          right: 0,
          child: Center(
            child: FloatingActionButton(
              child: const Icon(Icons.check),
              onPressed: () async {
                LoadingOverlay.of(context).show();
                final croppedImgPath = await DocCropper.crop(
                    widget.imgPath, widget.edgeDetectionResult);
                if (mounted && croppedImgPath != null) {
                  debugPrint("croppedImgPath=$croppedImgPath");
                  LoadingOverlay.of(context).hide();
                  Navigator.push(
                      context,
                      MaterialPageRoute(
                        builder: (context) => LoadingOverlay(
                            child: DocCleanPage(imgPath: croppedImgPath)),
                      ));
                }
              },
            ),
          ),
        )
      ]),
    );
  }
}