implemented making a pdf from DetailPage.dart and croping image to 1:1 format

lib/AddPage.dart

@@ -1,8 +1,10 @@
 import 'dart:io';
+import 'dart:math';
 import 'package:firebase_storage/firebase_storage.dart';
 import 'package:flutter/material.dart';
 import 'package:image_picker/image_picker.dart';
 import 'package:cloud_firestore/cloud_firestore.dart';
+import 'package:image/image.dart' as img;
 
 
 class AddScreen extends StatefulWidget {
@@ -35,6 +37,27 @@ class _AddScreenState extends State<AddScreen> {
     return fileSize <= maxSizeInBytes;
   }
 
+  Future<File> _cropImage(File imageFile) async {
+    final originalImage = img.decodeImage(await imageFile.readAsBytes());
+
+    if (originalImage != null) {
+      int originSize = min(originalImage.width, originalImage.height);
+      final croppedImage = img.copyCrop(
+          originalImage,
+          x: (originalImage.width - originSize)~/2,
+          y: (originalImage.height - originSize)~/2,
+          width: originSize,
+          height: originSize
+      );
+      final newPath = imageFile.path.substring(0, imageFile.path.lastIndexOf('/'));
+      final newFile = File('$newPath/cropped.jpg');
+      await newFile.writeAsBytes(img.encodePng(croppedImage));
+      return newFile;
+    } else {
+      throw Exception('Unable to decode image file.');
+    }
+  }
+
   Future<void> _getImage(ImageSource source) async {
     final pickedFile = await ImagePicker().pickImage(source: source);
 
@@ -42,8 +65,9 @@ class _AddScreenState extends State<AddScreen> {
       final tempFile = File(pickedFile.path);
       final bool isValid = await isFileSizeValid(tempFile, 10);
       if (isValid) {
+        File croppedFile = await _cropImage(tempFile);  // Bild zuschneiden
         setState(() {
-          _imageFile = tempFile;
+          _imageFile = croppedFile;
         });
       } else {
         ScaffoldMessenger.of(context).showSnackBar(
@@ -53,6 +77,7 @@ class _AddScreenState extends State<AddScreen> {
     }
   }
 
+
   Future<void> addNewElementToFirestore(String title, String description, File imageFile, {required Function(bool) onComplete}) async {
     String collectionName;
     if (_selectedIndex == 0) {

lib/DetailPage.dart

@@ -1,5 +1,9 @@
-import 'package:cached_network_image/cached_network_image.dart';
+import 'dart:typed_data';
+import 'package:pdf/widgets.dart' as pdfWidgets;
+import 'package:printing/printing.dart';
 import 'package:flutter/material.dart';
+import 'package:http/http.dart' as http;
+import 'package:cached_network_image/cached_network_image.dart';
 
 class DetailPage extends StatelessWidget {
   final String title;
@@ -15,11 +19,62 @@ class DetailPage extends StatelessWidget {
     required this.imageUrl,
   }) : super(key: key);
 
+
+  Future<void> _printPdf() async {
+    final pdf = pdfWidgets.Document();
+    final image = await _loadNetworkImage(imageUrl);
+
+    pdf.addPage(
+      pdfWidgets.MultiPage(
+        build: (context) => [
+          pdfWidgets.Center(
+            child: pdfWidgets.SizedBox(
+              width: double.infinity, // Die Breite auf die maximal mögliche Breite setzen
+              child: pdfWidgets.AspectRatio(
+                aspectRatio: 1, // Sie können das Seitenverhältnis entsprechend Ihrem Bild anpassen
+                child: pdfWidgets.Image(image),
+              ),
+            ),
+          ),
+          pdfWidgets.Text(
+              title,
+              style: pdfWidgets.TextStyle(
+                  fontSize: 20,
+                  fontWeight: pdfWidgets.FontWeight.bold // Titel fett
+              )
+          ),
+          pdfWidgets.Text(datum, style: const pdfWidgets.TextStyle(fontSize: 14, )),
+          pdfWidgets.Paragraph(text: description, style: const pdfWidgets.TextStyle(fontSize: 12)),
+        ],
+      ),
+    );
+    await Printing.sharePdf(bytes: await pdf.save(), filename: '$title.pdf');
+  }
+
+  Future<pdfWidgets.ImageProvider> _loadNetworkImage(String url) async {
+    final response = await http.get(Uri.parse(url));
+
+    if (response.statusCode != 200) {
+      throw Exception('Failed to load network image.');
+    }
+
+    final Uint8List bytes = response.bodyBytes;
+    final imageProvider = pdfWidgets.MemoryImage(bytes);
+
+    return imageProvider;
+  }
+
   @override
   Widget build(BuildContext context) {
     return Scaffold(
       appBar: AppBar(
         title: Text(title),
+        actions: <Widget>[
+          IconButton(
+            icon: const Icon(Icons.picture_as_pdf),
+            onPressed: _printPdf,
+          ),
+        ],
       ),
       body: SingleChildScrollView(
         child: Column(