我正在使用HTML / CSS创建PDF视图。因此,在某些情况下,我们需要从本地资产文件夹渲染图像。当我们尝试从资源渲染文件时,不显示图像。如何解决这个问题?
IOS的截图:
完整源代码:
RenderHtml.dart
import 'package:flutter/material.dart';
import 'dart:async';
import 'dart:io';
import 'package:flutter_full_pdf_viewer/flutter_full_pdf_viewer.dart';
import 'package:flutter_html_to_pdf/flutter_html_to_pdf.dart';
import 'package:path_provider/path_provider.dart';
void main() {
runApp(MaterialApp(
home: MyApp(),
));
}
var base64Image = "";
class MyApp extends StatefulWidget {
@override
_MyAppState createState() => _MyAppState();
}
class _MyAppState extends State<MyApp> {
String generatedPdfFilePath;
@override
void initState() {
super.initState();
generateExampleDocument();
}
Future<void> generateExampleDocument() async {
var htmlContent = """
<!DOCTYPE html>
<html>
<head>
<style>
table, th, td {
border: 1px solid black;
border-collapse: collapse;
}
th, td, p {
padding: 5px;
text-align: left;
}
</style>
</head>
<body>
<h2>PDF Generated with flutter_html_to_pdf plugin</h2>
<table style="width:100%">
<caption>Sample HTML Table</caption>
<tr>
<th>Month</th>
<th>Savings</th>
</tr>
<tr>
<td>January</td>
<td>100</td>
</tr>
<tr>
<td>February</td>
<td>50</td>
</tr>
</table>
<p>Image loaded from web</p>
<img src="file:///storage/example/your_sample_image.png" alt="web-img">
<img src="https://i.imgur.com/wxaJsXF.png" alt="web-img">
<img src="file:///assets/profyl.jpg" alt="asset-img">
<img src="assets/profyl.jpg" alt="asset-img">
<img src="file:///storage/assets/profyl.png" alt="storage-img">
<img src="file:///android_asset/flutter_assets/assets/profyl.jpg" alt="android_asset-img">
<img src="data:image/png;base64, iVBORw0KGgoAAAANSUhEUgAAAAUA
AAAFCAYAAACNbyblAAAAHElEQVQI12P4//8/w38GIAXDIBKE0DHxgljNBAAO
9TXL0Y4OHwAAAABJRU5ErkJggg==" alt="Base64 Image" style="height: 90%;" />
</body>
</html>
""";
Directory appDocDir = await getApplicationDocumentsDirectory();
var targetPath = appDocDir.path;
var targetFileName = "example-pdf";
var generatedPdfFile = await FlutterHtmlToPdf.convertFromHtmlContent(
htmlContent, targetPath, targetFileName);
generatedPdfFilePath = generatedPdfFile.path;
}
@override
Widget build(BuildContext context) {
return MaterialApp(
home: Scaffold(
appBar: AppBar(),
body: Center(
child: RaisedButton(
child: Text("Open Generated PDF Preview"),
onPressed: () => Navigator.push(
context,
MaterialPageRoute(
builder: (context) => PDFViewerScaffold(
appBar: AppBar(title: Text("Generated PDF Document")),
path: generatedPdfFilePath)),
),
),
),
));
}
}
pubspec.yaml
flutter_full_pdf_viewer: ^1.0.4
flutter_html_to_pdf: ^0.5.2
printing: ^2.1.7
path_provider: ^1.3.0
我通常使用http://fluttericon.com来生成自己的字体文件,该文件可以包含来自许多主要库(例如“ Font Awesome”等)的图标。使用该工具,您可以下载ttf文件(以及配置文件,可用于在上述页面上进一步处理项目)。您还将获得一个dart文件,以方便引用您的图标。
此ttf文件应放在资产文件夹或子文件夹中的某个位置。然后在pubspec中执行:
fonts:
- family: MyFont
fonts:
- asset: assets/fonts/MyFont.ttf
将生成的带有图标常量的dart文件放入项目中的某个位置。我们称之为myfont_icons.dart。它看起来应该像这样:
import 'package:flutter/widgets.dart';
class MyFont {
MyFont._();
static const _kFontFam = 'MyFont';
static const IconData people = const IconData(0xe802, fontFamily: _kFontFam);
static const IconData th_list = const IconData(0xe803, fontFamily: _kFontFam);
}
因此,与使用CSS样式表进行Web开发的Web开发基本相同,在CSS样式表中,所有图标都由css类定义。
[在类中使用图标时,只需导入该dart文件并按如下方式使用它:
Icon(
MyFont.people,
size: 94,
),
您是否已将pubspec.yaml中的Assets文件夹直接包含在颤振内部,如下所示:>
flutter: assets: - assets/profyl.png
或
flutter: assets: - assets
用于添加整个资产文件夹