Question

我有一个很奇怪的问题。我有一个手表应用程序，正在尝试以编程方式显示图像。调试代码时，我可以看到图像已正确加载，但是在模拟器或真实设备上却看不到图像。我已经在监视和扩展捆绑资源中添加了该图像。

首先，我使用下面的代码打开视图。

 NSArray *objects =[NSArray arrayWithObjects:@"MainPageView",@"InterfaceController",@"PoseImageView",nil];            
[self presentControllerWithNames:objects contexts:nil];

在PoseImageView内部，我试图显示具有以下内容的图像：

UIImage *imgTest = [UIImage imageNamed:[NSString stringWithFormat:@"1.jpg", strAngle]];  // I can see 1.jpg in debugger
[_imgPose setImage: imgTest];

手表或模拟器上没有图像。我想知道如何解决此问题。

注意：从资产中也无法加载。

注2：仅当视图为初始视图时，我才能显示图像。

Answer 1

您正在尝试将imageNamed用于.jpg，它将不起作用。尝试使用

import 'dart:async';
import 'dart:convert';
import 'dart:io';

import 'package:flutter/material.dart';
import 'package:path_provider/path_provider.dart';

void main() {
  runApp(new MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return new MaterialApp(
      title: 'Path Provider',
      theme: new ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: new MyHomePage(title: 'Path Provider', storage: FileStorage(),),
    );
  }
}

class FileStorage {
  Future<String> get _localPath async {
    final directory = await getTemporaryDirectory();

    return directory.path;
  }

  Future<File> get _localFile async {
    final path = await _localPath;
    return File('$path/file.txt');
  }

  void readFile() {
    /* What to do? */
  }

  Future<Null> writeFile(String text) async {
    final file = await _localFile;

    IOSink sink = file.openWrite(mode: FileMode.append);
    sink.add(utf8.encode('$text'));
    await sink.flush();
    await sink.close();
  }
}



class MyHomePage extends StatefulWidget {
  final FileStorage storage;
  MyHomePage({Key key, this.title, this.storage}) : super(key: key);
  final String title;

  @override
   _MyHomePageState createState() => new _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  final myController = TextEditingController();

  @override
  void dispose() {
    // TODO: implement dispose
    myController.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    // TODO: implement build
    return new Scaffold(
      appBar: new AppBar(
        title: new Text('Testing'),
      ),
      body: new Column(
        mainAxisSize: MainAxisSize.max,
        mainAxisAlignment: MainAxisAlignment.start,
        crossAxisAlignment: CrossAxisAlignment.stretch,
        children: <Widget>[
          Padding(
            padding: const EdgeInsets.all(8.0),
            child: new TextField(
              controller: myController,
              decoration: new InputDecoration(
                hintText: 'Enter the text',
              ),
            ),
          ),
          // StreamBuilder(
          //   stream: widget.storage.readCounter().asStream(),
          // )
        ],
      ),
      floatingActionButton: new FloatingActionButton(
        child: new Icon(Icons.save_alt),
        onPressed: () {
          widget.storage.writeFile(myController.text);
        },
      ),
    );
  }
}

图像无法在Watch App上以编程方式看到

1 个答案: