simple_html_css

Simple Html CSS

This is a fork of css_text_for_flutter

This package makes it easy for you to convert HTML with inline CSS content into RichText widgets. It supports most CSS properties that are relevant to text content, except for a few. Also gives the ability to override the styles of the content passed in.

NOTE: This is not an alternative to webview packages. This package only deals with text.

Here's a sample HTML content with inline CSS styles:

<body>
    <h1 style='color: white; font-size:50px; font-style:italic; 
    background-color: rgb(0,122,255); font-weight:100;)'> Hello word! </h1>
    <h1 style=''>Convert your <span style='color:lightseagreen;'>
    HTML</span> and <span style='color:dodgerblue'>CSS</span> 
    easily into RichText</h1>
    <p>Lorem ipsum dolor sit, consectetur adipiscing elit. Pellentesque in leo 
    id dui bibendum fringilla in et arcu. In vehicula vel est sed mattis.</p>
    <p><a href="https://google.com">Need more? click this link</a></p>
    <p>We all spell <span style='color:crimson; 
    text-decoration: underline wavy;'>recieve</span> wrong.<br />Some times we 
    delete <del>stuff</del></p>
    <div style='font-size:17px'>We write things that are 
    <span style='font-size:1.5em;'>Big,</span> <b>bold</b>&nbsp; or 
    <span style='color:brown'>colorful</span></div>
    <p style='font-family:times;'>Some different FONT with 
    <span style='background-color:lightcyan;'>this part highlighted</span></p>
    <div style='line-height:2; font-size:17px;'><b style='color: rgb(0,122,255); 
    font-weight:500;'>Finally some line heights.</b> Lorem ipsum dolor sit amet, 
    consectetur adipiscing elit. Pellentesque in leo id dui bibendum fringilla 
    in et arcu. In vehicula vel est sed mattis. Duis varius, sem non mattis.</div>
</body>

This package can automatically convert all the HTML content above into TextSpan objects or a RichText widget. Here's what the render will look like:

Getting Started

Using simple_html_css is extremely easy. First import the library in your Dart code:

import 'package:simple_html_css/simple_html_css.dart';

You can then create TextSpan from any HTML content by calling the HTML.toTextSpan() method. Which you can use to create a RichText widget.

String htmlContent = """
<p style="font-size:1.5em;">Hello World</p>
""";

RichText(
  text: HTML.toTextSpan(context, htmlContent),
  maxLines: 4,
  //...
  );

As a shortcut, you can also use the HTML.toRichText() method.

var myRichText = HTML.toRichText(context, htmlContent);

Container(
  child: myRichText,
);

Handling Links

Your HTML content can have links. To handle them, you must use the linksCallback optional parameter.

String htmlContent = """<span style="font-size:2em">
Please click <a href="https://pub.dartlang.org">here</a> or 
<a href="https://old.reddit.com">here</a>.<br/>
<br/>
Go ahead! Try it.
</span>""";

var myRichText = HTML.toRichText(context, htmlContent, linksCallback: (link) {
    // You can now use the url_launcher library to open the link.
    // Or you can handle the link in your app itself. This gives you
    // complete control over your links.
    // For now, let's just print it
    print(link);
});

Apply a default style

You can apply a global text sytle. This acts as the base text style of all content.

HTML.toTextSpan(
      context,
      htmlContent,
      defaultTextStyle: TextStyle(
        color: Colors.grey[700],
        fontSize: 12,
        // etc etc
      ),
    );

Overriding styles

You can override the inline styles and apply global styles for each of the HTML tags in your HTML content.

String htmlContent =
   """
   <p>This has no font size css property, but global style will be applied</p>
   <a style='color: orange;'>The inline color for this is orange, but it will 
   get overridden by global style defined below</a>
   """;

HTML.toTextSpan(
      context,
      htmlContent,
      overrideStyle: {
        "p": TextStyle(fontSize: 17.3),
        "a": TextStyle(color: Colors.red),
        // specify any tag not just the supported ones,
        // and apply TextStyles to them and/override them
      },
    );

Supported HTML Tags

Supports all tags which prints text normally like p, div, span, body etc.
And the following special tags which change the text appearance

• <h1> - <h6>
• <b> <strong>
• <br> <br />
• <i> <em>
• <u>
• <strike> <del> <s>
• <a> - anchor tags with link click callback

Supported CSS properties (text related)

supported Css property	supported value(s)
font-weight	100 to 900, normal, medium, bold
color	css color name like: red, orangered etc. or rgb(0, 0, 255) or rgba(0, 0, 50, 0.5) or Hex #eee/#ff00ff/#ff005522
background-color	same as above
font-style	italic and normal
font-family	any valid font family. eg: times
font-size	eg: 18px or 1.5em
text-decoration	underline, overline, none, line, dotted, dashed, wavy
line-height	any valid value. eg: 1.5

Partially supported HTML tags

<ol> <ul> <li> These tags will be rendered on new lines, but without the number or symbol

Workaround for text not rendering properly

If you experienced any rendering issue like this, It is becuase you need to have the build context of a Material parent Widget such as a Scaffold or Material.

To get the context directly a quick workaround is adding a Builder

Scaffold(
  body: Builder(
    builder: (context) {
        return RichText(
          text: HTML.toTextSpan(context, htmlContent),
      );
    },
  ),
)

TODO

• Add support <ul> tag with correct indentation
• Add support <ol> tag with correct indentation