blocks|key|570778|text|您可以使用resolve+ImageProvider获取ImageStream，然后在图像准备就绪时使用addListener通知。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|570779|​|570780|📷|atomic|570781|570782|import+'dart:ui'+as+ui;
import+'dart:async';
import+'package:flutter/material.dart';
import+'package:flutter/services.dart';

void+main()+{
++runApp(new+MaterialApp(
++++home:+new+MyHomePage(),
++));
}

class+MyHomePage+extends+StatelessWidget+{

++Future<ui.Image>+_getImage()+{
++++Completer<ui.Image>+completer+=+new+Completer<ui.Image>();
++++new+NetworkImage('https://i.stack.imgur.com/lkd0a.png')
++++++.resolve(new+ImageConfiguration())
++++++.addListener((ImageInfo+info,+bool+_)+=>+completer.complete(info.image));
++++return+completer.future;
++}

++Widget+build(BuildContext+context)+{
++++return+new+Scaffold(
++++++appBar:+new+AppBar(
++++++++title:+new+Text("Image+Dimensions+Example"),
++++++),
++++++body:+new+Center(
++++++++child:+new+FutureBuilder<ui.Image>(
++++++++++future:+_getImage(),
++++++++++builder:+(BuildContext+context,+AsyncSnapshot<ui.Image>+snapshot)+{
++++++++++++if+(snapshot.hasData)+{
++++++++++++++ui.Image+image+=+snapshot.data;
++++++++++++++return+new+Text(
++++++++++++++++'${image.width}x${image.height}',
++++++++++++++++style:+Theme.of(context).textTheme.display4);
++++++++++++}+else+{
++++++++++++++return+new+Text('Loading...');
++++++++++++}
++++++++++},
++++++++),
++++++),
++++);
++}
}|code-block|syntax|javascript|570783|entityMap|0|LINK|mutability|MUTABLE|url|https://docs.flutter.io/flutter/services/ImageProvider/resolve.html|1|https://docs.flutter.io/flutter/services/ImageProvider-class.html|2|https://docs.flutter.io/flutter/services/ImageStream-class.html|3|https://docs.flutter.io/flutter/services/ImageStream/addListener.html|4|IMAGE|IMMUTABLE|imageUrl|https://developer.qcloudimg.com/http-save/yehe-900000/2bb3c2c3a36584450d7884bf88efc137.png|imageAlt^0|5|7|D|D|S|B|1G|B|5|7|0|D|D|1|S|B|2|1G|B|3|0|0|0|1|4|0|0|0^^$0|@$1|2|3|4|5|6|7|1A|8|@$9|1B|A|1C|B|C]|$9|1D|A|1E|B|C]|$9|1F|A|1G|B|C]|$9|1H|A|1I|B|C]]|D|@$9|1J|A|1K|1|1L]|$9|1M|A|1N|1|1O]|$9|1P|A|1Q|1|1R]|$9|1S|A|1T|1|1U]]|E|$]]|$1|F|3|G|5|6|7|1V|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|1W|8|@]|D|@$9|1X|A|1Y|1|1Z]]|E|$]]|$1|K|3|G|5|6|7|20|8|@]|D|@]|E|$]]|$1|L|3|M|5|N|7|21|8|@]|D|@]|E|$O|P]]|$1|Q|3|-4|5|6|7|22|8|@]|D|@]|E|$]]]|R|$S|$5|T|U|V|E|$W|X]]|Y|$5|T|U|V|E|$W|Z]]|10|$5|T|U|V|E|$W|11]]|12|$5|T|U|V|E|$W|13]]|14|$5|15|U|16|E|$17|18|19|-4]]]]

You can <a href="https://docs.flutter.io/flutter/services/ImageProvider/resolve.html" rel="noreferrer"><code>resolve</code></a> the <a href="https://docs.flutter.io/flutter/services/ImageProvider-class.html" rel="noreferrer"><code>ImageProvider</code></a> to get an <a href="https://docs.flutter.io/flutter/services/ImageStream-class.html" rel="noreferrer"><code>ImageStream</code></a>, then use <a href="https://docs.flutter.io/flutter/services/ImageStream/addListener.html" rel="noreferrer"><code>addListener</code></a> to be notified when the image is ready.

<a href="https://i.stack.imgur.com/ecJbR.png" rel="noreferrer"><img src="https://i.stack.imgur.com/ecJbR.png" alt="screenshot"></a>

<pre><code>import 'dart:ui' as ui;
import 'dart:async';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';

void main() {
 runApp(new MaterialApp(
 home: new MyHomePage(),
 ));
}

class MyHomePage extends StatelessWidget {

 Future&lt;ui.Image&gt; _getImage() {
 Completer&lt;ui.Image&gt; completer = new Completer&lt;ui.Image&gt;();
 new NetworkImage('https://i.stack.imgur.com/lkd0a.png')
 .resolve(new ImageConfiguration())
 .addListener((ImageInfo info, bool _) =&gt; completer.complete(info.image));
 return completer.future;
 }

 Widget build(BuildContext context) {
 return new Scaffold(
 appBar: new AppBar(
 title: new Text("Image Dimensions Example"),
 ),
 body: new Center(
 child: new FutureBuilder&lt;ui.Image&gt;(
 future: _getImage(),
 builder: (BuildContext context, AsyncSnapshot&lt;ui.Image&gt; snapshot) {
 if (snapshot.hasData) {
 ui.Image image = snapshot.data;
 return new Text(
 '${image.width}x${image.height}',
 style: Theme.of(context).textTheme.display4);
 } else {
 return new Text('Loading...');
 }
 },
 ),
 ),
 );
 }
}
</code></pre>

blocks|key|1908597|text|更新的解决方案：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1908598|随着新版本的颤振，旧的解决方案是过时的。现在addListener需要一个ImageStreamListener。|offset|length|style|CODE|1908599|Widget+build(BuildContext+context)+{
++++Image+image+=+new+Image.network('https://i.stack.imgur.com/lkd0a.png');
++++Completer<ui.Image>+completer+=+new+Completer<ui.Image>();
++++image.image
++++++.resolve(new+ImageConfiguration())
++++++.addListener(ImageStreamListener((ImageInfo+info,+bool+_)+{+
++++++++completer.complete(info.image));
++++++})
++++...
++++...|code-block|syntax|javascript|1908600|原文：|1908601|如果您已经有了一个Image小部件，您可以通过在其ImageStream的ImageProvider上调用resolve来读取它的resolve。|1908602|​|1908603|📷|atomic|1908604|1908605|import+'dart:ui'+as+ui;
import+'dart:async';
import+'package:flutter/material.dart';
import+'package:flutter/services.dart';

void+main()+{
++runApp(new+MaterialApp(
++++home:+new+MyHomePage(),
++));
}

class+MyHomePage+extends+StatelessWidget+{

++Widget+build(BuildContext+context)+{
++++Image+image+=+new+Image.network('https://i.stack.imgur.com/lkd0a.png');
++++Completer<ui.Image>+completer+=+new+Completer<ui.Image>();
++++image.image
++++++.resolve(new+ImageConfiguration())
++++++.addListener((ImageInfo+info,+bool+_)+=>+completer.complete(info.image));
++++return+new+Scaffold(
++++++appBar:+new+AppBar(
++++++++title:+new+Text("Image+Dimensions+Example"),
++++++),
++++++body:+new+ListView(
++++++++children:+[
++++++++++new+FutureBuilder<ui.Image>(
++++++++++++future:+completer.future,
++++++++++++builder:+(BuildContext+context,+AsyncSnapshot<ui.Image>+snapshot)+{
++++++++++++++if+(snapshot.hasData)+{
++++++++++++++++return+new+Text(
++++++++++++++++++'${snapshot.data.width}x${snapshot.data.height}',
++++++++++++++++++style:+Theme.of(context).textTheme.display3,
++++++++++++++++);
++++++++++++++}+else+{
++++++++++++++++return+new+Text('Loading...');
++++++++++++++}
++++++++++++},
++++++++++),
++++++++++image,
++++++++],
++++++),
++++);
++}
}|1908606|entityMap|0|IMAGE|mutability|IMMUTABLE|imageUrl|https://developer.qcloudimg.com/http-save/yehe-900000/7cf0e41eb68488c4b590afbcef4c013b.jpg|imageAlt^0|0|M|B|11|J|0|0|0|9|5|P|B|11|D|1H|7|1T|7|0|0|0|1|0|0|0|0^^$0|@$1|2|3|4|5|6|7|17|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|18|8|@$D|19|E|1A|F|G]|$D|1B|E|1C|F|G]]|9|@]|A|$]]|$1|H|3|I|5|J|7|1D|8|@]|9|@]|A|$K|L]]|$1|M|3|N|5|6|7|1E|8|@]|9|@]|A|$]]|$1|O|3|P|5|6|7|1F|8|@$D|1G|E|1H|F|G]|$D|1I|E|1J|F|G]|$D|1K|E|1L|F|G]|$D|1M|E|1N|F|G]|$D|1O|E|1P|F|G]]|9|@]|A|$]]|$1|Q|3|R|5|6|7|1Q|8|@]|9|@]|A|$]]|$1|S|3|T|5|U|7|1R|8|@]|9|@$D|1S|E|1T|1|1U]]|A|$]]|$1|V|3|R|5|6|7|1V|8|@]|9|@]|A|$]]|$1|W|3|X|5|J|7|1W|8|@]|9|@]|A|$K|L]]|$1|Y|3|-4|5|6|7|1X|8|@]|9|@]|A|$]]]|Z|$10|$5|11|12|13|A|$14|15|16|-4]]]]

<h2>UPDATED SOLUTION:</h2>
With the new version of flutter old solution is obsolete. Now the <code>addListener</code> needs an <code>ImageStreamListener</code>.
<pre><code>Widget build(BuildContext context) {
 Image image = new Image.network('https://i.stack.imgur.com/lkd0a.png');
 Completer&lt;ui.Image&gt; completer = new Completer&lt;ui.Image&gt;();
 image.image
 .resolve(new ImageConfiguration())
 .addListener(ImageStreamListener((ImageInfo info, bool _) { 
 completer.complete(info.image));
 })
 ...
 ...
</code></pre>
<hr />
<h2>ORIGINAL VERSION:</h2>
If you already have an <code>Image</code> widget, you can read the <code>ImageStream</code> out of it by calling <code>resolve</code> on its <code>ImageProvider</code>.
<a href="https://i.stack.imgur.com/HnVmB.jpg" rel="noreferrer"><img src="https://i.stack.imgur.com/HnVmB.jpg" alt="screenshot" /></a>
<pre><code>import 'dart:ui' as ui;
import 'dart:async';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';

void main() {
 runApp(new MaterialApp(
 home: new MyHomePage(),
 ));
}

class MyHomePage extends StatelessWidget {

 Widget build(BuildContext context) {
 Image image = new Image.network('https://i.stack.imgur.com/lkd0a.png');
 Completer&lt;ui.Image&gt; completer = new Completer&lt;ui.Image&gt;();
 image.image
 .resolve(new ImageConfiguration())
 .addListener((ImageInfo info, bool _) =&gt; completer.complete(info.image));
 return new Scaffold(
 appBar: new AppBar(
 title: new Text(&quot;Image Dimensions Example&quot;),
 ),
 body: new ListView(
 children: [
 new FutureBuilder&lt;ui.Image&gt;(
 future: completer.future,
 builder: (BuildContext context, AsyncSnapshot&lt;ui.Image&gt; snapshot) {
 if (snapshot.hasData) {
 return new Text(
 '${snapshot.data.width}x${snapshot.data.height}',
 style: Theme.of(context).textTheme.display3,
 );
 } else {
 return new Text('Loading...');
 }
 },
 ),
 image,
 ],
 ),
 );
 }
}
</code></pre>

blocks|key|1908632|text|如果您只想要异步函数中的图像的宽度和高度，则其他答案似乎过于复杂。您可以像这样直接使用颤振库获得图像分辨率：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1908633|import+'dart:io';

File+image+=+new+File('image.png');+//+Or+any+other+way+to+get+a+File+instance.
var+decodedImage+=+await+decodeImageFromList(image.readAsBytesSync());
print(decodedImage.width);
print(decodedImage.height);|code-block|syntax|javascript|1908634|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

The other answers seem overly complicated if you just want the width and height of an image in an async function. You can get the image resolution using flutter lib directly like this:

<pre><code>import 'dart:io';

File image = new File('image.png'); // Or any other way to get a File instance.
var decodedImage = await decodeImageFromList(image.readAsBytesSync());
print(decodedImage.width);
print(decodedImage.height);
</code></pre>

blocks|key|570923|text|对于新版本的颤振旧解决方案不起作用的示例：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|570924|++image.image
++.resolve(new+ImageConfiguration())
++.addListener((ImageInfo+info,+bool+_)+=>+completer.complete(info.image));|code-block|syntax|javascript|570925|在工作版本下面|offset|length|style|BOLD|570926|_image.image
++++.resolve(new+ImageConfiguration())
++++.addListener(new+ImageStreamListener((ImageInfo+image,+bool+_)+{
++completer.complete(image.image);
}));|570927|entityMap^0|0|0|0|5|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|S|8|@$I|T|J|U|K|L]]|9|@]|A|$]]|$1|M|3|N|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|O|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|P|$]]

With new version of flutter old solution not working example:

<pre><code> image.image
 .resolve(new ImageConfiguration())
 .addListener((ImageInfo info, bool _) =&gt; completer.complete(info.image));
</code></pre>

Below the Working version:

<pre><code>_image.image
 .resolve(new ImageConfiguration())
 .addListener(new ImageStreamListener((ImageInfo image, bool _) {
 completer.complete(image.image);
}));
</code></pre>

blocks|key|570962|text|创建一个方法，例如：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|570963|Future<Size>+_calculateImageDimension()+{
++Completer<Size>+completer+=+Completer();
++Image+image+=+Image.network("https://i.stack.imgur.com/lkd0a.png");
++image.image.resolve(ImageConfiguration()).addListener(
++++ImageStreamListener(
++++++(ImageInfo+image,+bool+synchronousCall)+{
++++++++var+myImage+=+image.image;
++++++++Size+size+=+Size(myImage.width.toDouble(),+myImage.height.toDouble());
++++++++completer.complete(size);
++++++},
++++),
++);
++return+completer.future;
}|code-block|syntax|javascript|570964|并把它当作：|570965|_calculateImageDimension().then((size)+=>+print("size+=+${size}"));+//+487.0,696.0|570966|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

Create a method, like: 

<pre><code>Future&lt;Size&gt; _calculateImageDimension() {
 Completer&lt;Size&gt; completer = Completer();
 Image image = Image.network("https://i.stack.imgur.com/lkd0a.png");
 image.image.resolve(ImageConfiguration()).addListener(
 ImageStreamListener(
 (ImageInfo image, bool synchronousCall) {
 var myImage = image.image;
 Size size = Size(myImage.width.toDouble(), myImage.height.toDouble());
 completer.complete(size);
 },
 ),
 );
 return completer.future;
}
</code></pre>

And use it like: 

<pre><code>_calculateImageDimension().then((size) =&gt; print("size = ${size}")); // 487.0,696.0
</code></pre>

blocks|key|1908706|text|如果您不想使用FutureBuilder，也可以像下面这样使用await：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1908707|不要忘记导入图像。但是，由于有两个图像类，所以像这样导入它并与ui.Image一起使用|1908708|+import+'dart:ui'+as+ui|code-block|syntax|javascript|1908709|然后，您可以获取图像的尺寸如下所示。|1908710|+final+Image+image+=+Image(image:+AssetImage('assets/images/someimage.png'));
+Completer<ui.Image>+completer+=+new+Completer<ui.Image>();
++++image.image
++++++++.resolve(new+ImageConfiguration())
++++++++.addListener(new+ImageStreamListener((ImageInfo+image,+bool+_)+{
++++++completer.complete(image.image);
++++}));
+ui.Image+info+=+await+completer.future;
+int+width+=+info.width;
+int+height+=+info.height;|1908711|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|P|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|Q|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|R|8|@]|9|@]|A|$]]|$1|K|3|L|5|F|7|S|8|@]|9|@]|A|$G|H]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

If you don't want to use FutureBuilder or then, you can also use await like this:
Don't forget to import the Image. But as there are two Image classes, import it like this and use with ui.Image
<pre><code> import 'dart:ui' as ui
</code></pre>
Then you can fetch the dimensions of the image as follows.
<pre><code> final Image image = Image(image: AssetImage('assets/images/someimage.png'));
 Completer&lt;ui.Image&gt; completer = new Completer&lt;ui.Image&gt;();
 image.image
 .resolve(new ImageConfiguration())
 .addListener(new ImageStreamListener((ImageInfo image, bool _) {
 completer.complete(image.image);
 }));
 ui.Image info = await completer.future;
 int width = info.width;
 int height = info.height;
</code></pre>

blocks|key|1908733|text|如何检查从资产加载的图像维度的简单方法。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1908734|var+img+=+await+rootBundle.load("Your+image+path");
var+decodedImage+=+await+decodeImageFromList(img.buffer.asUint8List());
int+imgWidth+=+decodedImage.width;
int+imgHeight+=+decodedImage.height;|code-block|syntax|javascript|1908735|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

A simple way how to check image dimensions that is loaded from assets.
<pre><code>var img = await rootBundle.load(&quot;Your image path&quot;);
var decodedImage = await decodeImageFromList(img.buffer.asUint8List());
int imgWidth = decodedImage.width;
int imgHeight = decodedImage.height;
</code></pre>

blocks|key|1865977|text|这里有一个方便的助手函数，基于其他解决方案|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1865978|辅助函数|1865979|Future<ImageInfo>+getImageInfo(Image+img)+async+{
++final+c+=+new+Completer<ImageInfo>();
++img.image
++++.resolve(new+ImageConfiguration())++++++++
++++.addListener(new+ImageStreamListener((ImageInfo+i,+bool+_)+{
++++++c.complete(i);
++++}));
++return+c.future;++++
}|code-block|syntax|javascript|1865980|用法|1865981|Image+image+=+Image.network("https://example.com/pic.png");
ImageInfo+info+=+await+getImageInfo(image);|1865982|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|P|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|Q|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|R|8|@]|9|@]|A|$]]|$1|K|3|L|5|F|7|S|8|@]|9|@]|A|$G|H]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

Here's a handy helper function, based on other solutions
helper function
<pre class="lang-dart prettyprint-override"><code>Future&lt;ImageInfo&gt; getImageInfo(Image img) async {
 final c = new Completer&lt;ImageInfo&gt;();
 img.image
 .resolve(new ImageConfiguration()) 
 .addListener(new ImageStreamListener((ImageInfo i, bool _) {
 c.complete(i);
 }));
 return c.future; 
}
</code></pre>
usage
<pre><code>Image image = Image.network(&quot;https://example.com/pic.png&quot;);
ImageInfo info = await getImageInfo(image);
</code></pre>

blocks|key|1865987|text|获取资产图像大小的简单方法。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1865988|++++++Future<Size>+_loadAssetImageSize(String+asset)+async{
+++++++++ByteData+data+=+await+rootBundle.load(asset);
+++++++++ui.Codec+codec+=+await+
+++++++++ui.instantiateImageCodec(data.buffer.asUint8List());
+++++++++ui.FrameInfo+fi+=+await+codec.getNextFrame();
+++++++++return+Size(fi.image.width.toDouble(),+fi.image.height.toDouble());
++}|code-block|syntax|javascript|1865989|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Easy way to get asset images size.
<pre><code> Future&lt;Size&gt; _loadAssetImageSize(String asset) async{
 ByteData data = await rootBundle.load(asset);
 ui.Codec codec = await 
 ui.instantiateImageCodec(data.buffer.asUint8List());
 ui.FrameInfo fi = await codec.getNextFrame();
 return Size(fi.image.width.toDouble(), fi.image.height.toDouble());
 }
</code></pre>

blocks|key|571061|text|一种只想解码图像边界的方法：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|571062|++++final+buffer+=+await+ui.ImmutableBuffer.fromUint8List(bytes);
++++final+descriptor+=+await+ui.ImageDescriptor.encoded(buffer);

++++final+imageWidth+=+descriptor.width;
++++final+imageHeight+=+descriptor.height;
++++print("imageWidth:+$imageWidth,+imageHeight:+$imageHeight");

++++descriptor.dipose();
++++buffer.dipose();|code-block|syntax|javascript|571063|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

A way for who only want decode image bounds:
<pre class="lang-dart prettyprint-override"><code> final buffer = await ui.ImmutableBuffer.fromUint8List(bytes);
 final descriptor = await ui.ImageDescriptor.encoded(buffer);

 final imageWidth = descriptor.width;
 final imageHeight = descriptor.height;
 print(&quot;imageWidth: $imageWidth, imageHeight: $imageHeight&quot;);

 descriptor.dipose();
 buffer.dipose();
</code></pre>

blocks|key|1908828|text|任何一个解决方案都适用于颤振网吗？我无法找到任何解决方案，如果我尝试使用image_size_getter包，它会抛出"Error:+Unsupported：_Namespace“。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1908829|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

Does any of the solution works for Flutter web? I am unable to find any solution, if i try to use image_size_getter package its throws &quot;Error: Unsupported operation: _Namespace&quot;.

Assume I have declared my image in my pubspec.yaml like this:

<pre><code> assets:
 - assets/kitten.jpg
</code></pre>

And my Flutter code is this:

<pre><code>void main() {
 runApp(
 new Center(
 child: new Image.asset('assets/kitten.jpg'),
 ),
 );
}
</code></pre>

Now that I have a <code>new Image.asset()</code>, how do I determine the width and height of that image? For example, I just want to print out the image's width and height.

(It looks like <a href="https://docs.flutter.io/flutter/dart-ui/Image-class.html" rel="noreferrer">dart:ui's Image class</a> has width and height, but not sure how to go from widget's Image to dart:ui's Image.)

Thanks!

How do I determine the width and height of an image in Flutter?

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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假设我在pubspec.yaml中声明了自己的图像，如下所示：  assets:    - assets/kitten.jpg我的颤音代码是：void main() {  runApp(    new Center(      child: new Image.asset('assets/kitten.jpg'),  ...

问如何在颤振中确定图像的宽度和高度？
EN

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问如何在颤振中确定图像的宽度和高度？EN