flutter_social_textfield

TextEditingController and RichText / TextSpan builder with hashtag, url and mention detection with Regular Expressions. Also with tap support.


Keywords
dart, flutter, text-editing-controller
License
BSD-3-Clause

Documentation

flutter_social_textfield

Overview

A Flutter plugin that helps detection of common social media contents. The current position of the cursor is used for detecting content. Current detection types are:

  • HashTag (#): Texts start with #
  • Mention (@): Text start with @ sign
  • Web Links: Can detect web links
  • Emojis: can detect emojis [thanks @moazh]

You can see the supported detection types from DetectedType enum

enum DetectedType{
    mention, //By Default texts starting with @sign
    hashtag,  //By default, texts starting with #hashtag
    url, //By default texts starting with http://xxx.yyy or https://aaa.bbb 
    plain_text //Any other type falls into this.
}

You can change the relevant regex for that type if you want, which has been mentioned in Configuring the Text Editing Controller part.

Getting Started

SocialTextField is basically an improved Text Editing Controller, so you can just assign text controller to any text editing widget that you want.

_textEditingController = SocialTextEditingController();

TextField(
    controller: _textEditingController,
    expands: true,
    maxLines: null,
    minLines: null,
    decoration: InputDecoration(
    hintText: "Please Enter a Text"
    ),
)

Configuring the Text Editing Controller

SocialTextEditingController can be configured by calling configuration methods.

There are 2 setter methods for this.

  • setTextStyle: Change how detected content shown.

    setTextStyle(DetectedType.mention, TextStyle(...)

  • setRegexp: Override the detection regexp

    setRegexp(DetectedType.url, RegExp("your_own_regex_fr_this_type"))

It is recommended to set these values on initialization;

_textEditingController = SocialTextEditingController()
    ..setTextStyle(DetectedType.mention, TextStyle(color: Colors.purple,backgroundColor: Colors.purple.withAlpha(50)))
    ..setRegexp(DetectedType.url, RegExp("your_own_regex_fr_this_type"));

Listening Content Detection Events

One of the main reasons that i want to create this plugin was that i needed to listen detection events from different widgets. So flutter_social_textfield provides a stream for detections so you can subscribe and listen events when needed.

StreamSubscription<SocialContentDetection> _streamSubscription;

@override
void initState() {
super.initState();
_textEditingController = SocialTextEditingController()
..text = "Lorem ipsum amet."
..setTextStyle(DetectedType.mention, TextStyle(color: Colors.purple,backgroundColor: Colors.purple.withAlpha(50)))
..setTextStyle(DetectedType.url, TextStyle(color: Colors.blue, decoration: TextDecoration.underline))
..setTextStyle(DetectedType.hashtag, TextStyle(color: Colors.blue, fontWeight: FontWeight.w600));

//Subscribe to events
 _streamSubscription = _textEditingController.subscribeToDetection(onDetectContent);
}

void onDetectContent(SocialContentDetection detection){
 print("Detected Contet: $detection");
}

don't forget to unsubscribe on dispose.

@override
void dispose() {
    _streamSubscription.cancel();
    super.dispose();
}

The Stream Subscriptoin returns SocialContentDetection class:

class SocialContentDetection{
    final DetectedType type; //mention, url, hashtag, plan_text
    final TextRange range; //range of detected content
    final String text; //detected content
    SocialContentDetection(this.type, this.range, this.text);
    
    @override
    String toString() {
        return 'SocialContentDetection{type: $type, range: $range, text: $text}';
    }
}

DefaultSocialTextFieldController

I've implemented an experimental widget for ease of use. DefaultSocialTextFieldController puts the main content inside a Stack and allows users to show relevant content when curser comes over a detected content

As with version 0.0.9 There are 2 different types of presentation of detection content:

Detection Presentation Mode

DetectionPresentationMode.split_screen : Shows detection view but moving from bottom to determined widget size. useful for full screen textfields like text editors

DetectionPresentationMode.above_text_field : Useful for showing detection view from above the textfield. The location of textfield is detected from the FocusNode automatically.

Please notice the 'scrollPhysics' property of the TextField;

DefaultSocialTextFieldController(
        detectionPresentationMode: DetectionPresentationMode.above_text_field,
        focusNode: _focusNode,
        scrollController: _scrollController,
        textEditingController: _textEditingController,
        child: Container(
          padding: EdgeInsets.all(8),
          child: Column(
            mainAxisAlignment: MainAxisAlignment.start,
            children: <Widget>[
              Expanded(
                child: TextField(
                  scrollPhysics: ClampingScrollPhysics(), //Use this for unnecessary scroll bounces
                  scrollController: _scrollController,
                  focusNode: _focusNode,
                  controller: _textEditingController,
                  expands: true,
                  maxLines: null,
                  minLines: null,
                  decoration: InputDecoration(
                      hintText: "Please Enter a Text"
                  ),
                ),
              ),
            ],
          ),
        ),
        detectionBuilders: {
          DetectedType.mention:(context)=>mentionContent(height),
          DetectedType.hashtag:(context)=>hashtagContent(height),
          DetectedType.url:(context)=>urlContent(height)
        },
      )

DefaultSocialTextFieldController in action

Using DefaultSocialTextFieldController

An example usage of the DefaultSocialTextFieldController can be seen in the example project. The main goal is to provide an easy way to implement features that have been seen in most of the social media applications.

SocialTextSpanBuilder

flutter_social_textfield uses SocialTextSpanBuilder for rendering the text inside the attached textfield. So if you just want to show formatted text content instead of using inside an editor you can use it like this:

With version 0.0.3 you can also implement onTapDetection function for adding tap gestures to detected strings.

void initBuilder(){
    final Map<DetectedType, RegExp> _regularExpressions = {
        DetectedType.mention:atSignRegExp,
        DetectedType.hashtag:hashTagRegExp,
        DetectedType.url:urlRegex
    };

    final Map<DetectedType, TextStyle> _detectionTextStyles = {
        DetectedType.mention:TextStyle(...)
    };

    final TextStyle _defaultTextStyle = TextStyle();

    final _textSpanBuilder = SocialTextSpanBuilder(regularExpressions: _regularExpressions,defaultTextStyle:_defaultTextStyle,detectionTextStyles: _detectionTextStyles, onTapDetection: (detection){print("Tapped on detection: $detection");});
}

//And you can return RichText content bu calling build(context) method afterwards.
@override
    Widget build(BuildContext context) {
        var height = MediaQuery.of(context).size.height * 0.4;
        return Scaffold(
            appBar: AppBar(
                title: Text(widget.title),
            ),
        body: Container(
           child:RichText(
              text:_textSpanBuilder.build(context)
            )
        )// This trailing comma makes auto-formatting nicer for build methods.
    );  
}   

Acknowledgements

Thanks https://github.com/Bhupesh-V (@Bhupesh-V) for his contribution to url regex 👌

This widget's default regular expressions taken from this wonderful widget:

detectable_text_field