flutter - 未处理的异常 : RangeError (index): Index out of range: index should be less than

Question

尝试使用“pdf_dart”库保存 pdf 时遇到问题。
我认为问题与我从互联网下载以尝试附加到 pdf 的图像有关，但我不确定它是什么。

代码

import 'dart:io';
import 'package:app_formulario/models/Customer.dart';
import 'package:path_provider/path_provider.dart';
import 'package:pdf/pdf.dart' as pdfDart;
import 'package:pdf/widgets.dart';
import 'package:image/image.dart' as imageDart;
import 'package:flutter/material.dart' as materialDart;
import 'package:http/http.dart' as http;

class PDFBloc {
  PDFBloc() {
    final Document pdf = Document();

    http
        .get(
            "https://clsp.com.br/wp-content/uploads/2018/05/logo-clsp-500px.png")
        .then((onValue) {
      final image = pdfDart.PdfImage(
        pdf.document,
        image: onValue.bodyBytes,
        width: 300,
        height: 150,
      );

      pdf.addPage(Page(build: (Context context) {
        return Center(
          child: Image(image),
        ); // Center
      }));

      criarPDF(pdf);
    });
  }

void criarPDF(Document pdf) async {
    Directory appDocDir = await getApplicationDocumentsDirectory();
    String appDocPath = appDocDir.path;
    appDocPath = "/storage/emulated/0/Android/data/com.rwrd.app_formulario";

    final File file = File('$appDocPath/example.pdf');
    file.writeAsBytesSync(pdf.save());
  }

错误发生在我要保存带有图像的pdf时，也就是说，显然图像已正常下载，但是当将其插入pdf并尝试保存时，会导致错误。

我不知道我保存的方式是否正确，也许就是这样，但不幸的是，我无法在不完全浏览文件夹的情况下访问该文件夹。

错误堆栈

E/flutter (18670): [ERROR:flutter/lib/ui/ui_dart_state.cc(157)] Unhandled Exception: RangeError (index): Index out of range: index should be less than 6307: 6308
E/flutter (18670): #0      Uint8List.[]  (dart:typed_data-patch/typed_data_patch.dart:2209:7)
E/flutter (18670): #1      PdfImage._prepare 
package:pdf/src/image.dart:183
E/flutter (18670): #2      PdfObject._write 
package:pdf/src/object.dart:53
E/flutter (18670): #3      PdfOutput.write 
package:pdf/src/output.dart:69
E/flutter (18670): #4      SetMixin.forEach  (dart:collection/set.dart:148:30)
E/flutter (18670): #5      PdfDocument._write 
package:pdf/src/document.dart:168
E/flutter (18670): #6      PdfDocument.save 
package:pdf/src/document.dart:176
E/flutter (18670): #7      Document.save 
package:pdf/widgets/document.dart:71
E/flutter (18670): #8      PDFBloc.criarPDF 
package:app_formulario/blocs/pdfBloc.dart:53
E/flutter (18670): <asynchronous suspension>
E/flutter (18670): #9      new PDFBloc.<anonymous closure> 
package:app_formulario/blocs/pdfBloc.dart:35
E/flutter (18670): #10     _rootRunUnary  (dart:async/zone.dart:1134:38)
E/flutter (18670): #11     _CustomZone.runUnary  (dart:async/zone.dart:1031:19)
E/flutter (18670): #12     _FutureListener.handleValue  (dart:async/future_impl.dart:139:18)
E/flutter (18670): #13     Future._propagateToListeners.handleValueCallback  (dart:async/future_impl.dart:680:45)
E/flutter (18670): #14     Future._propagateToListeners  (dart:async/future_impl.dart:709:32)
E/flutter (18670): #15     Future._completeWithValue  (dart:async/future_impl.dart:524:5)
E/flutter (18670): #16     _AsyncAwaitCompleter.complete  (dart:async-patch/async_patch.dart:32:15)
E/flutter (18670): #17     _completeOnAsyncReturn  (dart:async-patch/async_patch.dart:290:13)
E/flutter (18670): #18     _withClient (package:http/http.dart)
E/flutter (18670): <asynchronous suspension>
E/flutter (18670): #19     get 
package:http/http.dart:46
E/flutter (18670): #20     new PDFBloc 
package:app_formulario/blocs/pdfBloc.dart:18
E/flutter (18670): #21     FormBloc._recoverCustomerInformations 
package:app_formulario/blocs/formBloc.dart:37
E/flutter (18670): #22     _rootRunUnary  (dart:async/zone.dart:1134:38)
E/flutter (18670): #23     _CustomZone.runUnary  (dart:async/zone.dart:1031:19)
E/flutter (18670): #24     _CustomZone.runUnaryGuarded  (dart:async/zone.dart:933:7)
E/flutter (18670): #25     _BufferingStreamSubscription._sendData  (dart:async/stream_impl.dart:338:11)
E/flutter (18670): #26     _DelayedData.perform  (dart:async/stream_impl.dart:593:14)
E/flutter (18670): #27     _StreamImplEvents.handleNext  (dart:async/stream_impl.dart:709:11)
E/flutter (18670): #28     _PendingEvents.schedule.<anonymous closure>  (dart:async/stream_impl.dart:669:7)
E/flutter (18670): #29     _rootRun  (dart:async/zone.dart:1122:38)
E/flutter (18670): #30     _CustomZone.run  (dart:async/zone.dart:1023:19)
E/flutter (18670): #31     _CustomZone.runGuarded  (dart:async/zone.dart:925:7)
E/flutter (18670): #32     _CustomZone.bindCallbackGuarded.<anonymous closure>  (dart:async/zone.dart:965:23)
E/flutter (18670): #33     _rootRun  (dart:async/zone.dart:1126:13)
E/flutter (18670): #34     _CustomZone.run  (dart:async/zone.dart:1023:19)
E/flutter (18670): #35     _CustomZone.runGuarded  (dart:async/zone.dart:925:7)
E/flutter (18670): #36     _CustomZone.bindCallbackGuarded.<anonymous closure>  (dart:async/zone.dart:965:23)
E/flutter (18670): #37     _microtaskLoop  (dart:async/schedule_microtask.dart:43:21)
E/flutter (18670): #38     _startMicrotaskLoop  (dart:async/schedule_microtask.dart:52:5)
E/flutter (18670):

Answer 1

将pdf图像小部件更改为此，

final image = pdfDart.PdfImage.jpeg(
    pdf.document,
    image: onValue.bodyBytes,
);

现在，您的图像应该出现在 pdf 中，但是如果您想固定高度和宽度，则必须调整图像大小。