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Flutter linux机器上颤振中的打印错误_Flutter_Dart_Printing - Fatal编程技术网

Flutter linux机器上颤振中的打印错误

Flutter linux机器上颤振中的打印错误,flutter,dart,printing,Flutter,Dart,Printing,我想在Linux机器上打印一个颤振小部件 我的依赖项: pdf: ^3.3.0 printing: ^5.2.1 我的构建功能 @override Widget build(BuildContext context) { return Scaffold( appBar: AppBar( title: Text(widget.title), ), body: PdfPreview( build: (forma

我想在Linux机器上打印一个颤振小部件

我的依赖项:

  pdf: ^3.3.0
  printing: ^5.2.1
我的构建功能

@override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: PdfPreview(
        build: (format) => _generatePdf(format, 'test'),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: () async {
          await Printing.layoutPdf(
              onLayout: (format) => _generatePdf(format, 'Test'));
        },
        tooltip: 'Increment',
        child: Icon(Icons.add),
      ),
    );
  }
和我的_generatePdf函数:

Future<Uint8List> _generatePdf(PdfPageFormat format, String title) async {
    final pdf = pw.Document();

    pdf.addPage(
      pw.Page(
        pageFormat: format,
        build: (context) => pw.Center(
          child: pw.Text('Hello World!'),
        ),
      ),
    );

    return pdf.save();
  }
Future\u generatePdf(PdfPageFormat格式,字符串标题)异步{
最终pdf=pw.Document();
pdf.addPage(
第页(
pageFormat:format,
构建:(上下文)=>pw.Center(
child:pw.Text('Hello World!'),
),
),
);
返回pdf.save();
}
我从打印中得到的错误是:

/build/libproxy-1BEpaZ/libproxy-0.4.15/libmodman/module_manager.hpp:58: std::vector<T*> libmodman::module_manager::get_extensions() const [with T = libproxy::network_extension]: Assertion `obj != NULL' failed.
Lost connection to device.
/build/libproxy-1BEpaZ/libproxy-0.4.15/libmodman/module_-manager.hpp:58:std::vector libmodman::module_-manager::get_extensions()const[with T=libproxy::network_extension]:断言'obj!=“NULL”失败。
与设备的连接中断。
我现在正想办法解决这个问题。 蒂亚