doctor_app_flutter/lib/widgets/shared/Text.dart

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

class Texts extends StatefulWidget {

  final String text;
  final String variant;
  final Color color;
  final bool bold;
  final bool regular;
  final bool medium;
  final int maxLength;
  final bool italic;
  final TextAlign textAlign;
  final int maxLines;
  final bool readMore;
  final String style;
  final bool allowExpand;

  Texts(this.text, {Key key, this.variant, this.color,
    this.bold, this.regular, this.medium, this.allowExpand = true,
    this.italic:false, this.textAlign, this.maxLength=60,
    this.maxLines, this.readMore=false, this.style
  }) : super(key: key);

  @override
  _TextsState createState() => _TextsState();
}

class _TextsState extends State<Texts> {
  bool hidden = false;
  String text = "";

  @override
  void didUpdateWidget(Texts oldWidget) {
    setState(() {
      if (widget.style=="overline")
        text = widget.text.toUpperCase();
      else {
        text = widget.text;
      }
    });
    super.didUpdateWidget(oldWidget);
  }

  @override
  void initState() {
    hidden = widget.readMore;
    if (widget.style=="overline")
      text = widget.text.toUpperCase();
    else {
      text = widget.text;
    }
    super.initState();
  }

  double _getFontSize () {
    switch (widget.variant) {
      case "heading0":
        return 40.0;
      case "heading":
        return 32.0;
      case "heading2":
        return 28.0;
      case "heading3":
        return 18.0;
      case "body1":
        return 18.0;
      case "body2":
        return 20.0;
      case "body2Link":
        return 16.0;
      case "caption":
        return 16.0;
      case "caption2":
        return 14.0;
      case "bodyText":
        return 15.0;
      case "bodyText2":
        return 17.0;
      case "caption3":
        return 12.0;
      case "caption4":
        return 9.0;
      case "overline":
        return 11.0;
      case "date":
        return 24.0;
      default:
        return 16.0;
    }
  }

  FontWeight _getFontWeight () {
    if (widget.bold ?? false) {
      return FontWeight.w900;
    } else if (widget.regular ?? false) {
      return FontWeight.w500;
    } else if (widget.medium ?? false) {
      return FontWeight.w800;
    }
    else {
      if (widget.style==null) {
        switch (widget.variant) {
          case "heading":
            return FontWeight.w900;
          case "heading2":
            return FontWeight.w900;
          case "heading3":
            return FontWeight.w900;
          case "body1":
            return FontWeight.w800;
          case "body2":
            return FontWeight.w900;
          case "body2Link":
            return FontWeight.w800;
          case "caption":
            return FontWeight.w700;
          case "caption2":
            return FontWeight.w700;
          case "bodyText":
            return FontWeight.w500;
          case "bodyText2":
            return FontWeight.w500;
          case "caption3":
            return FontWeight.w600;
          case "caption4":
            return FontWeight.w600;
          case "overline":
            return FontWeight.w800;
          case "date":
            return FontWeight.w900;
          default:
            return FontWeight.w500;
        }
      } else {
        return null;
      }

    }
  }

  @override
  Widget build(BuildContext context) {

    TextStyle _getFontStyle () {
      switch (widget.style) {
        case "headline2":
          return Theme.of(context).textTheme.headline2;
        case "headline3":
          return Theme.of(context).textTheme.headline3;
        case "headline4":
          return Theme.of(context).textTheme.headline4;
        case "headline5":
          return Theme.of(context).textTheme.headline5;
        case "headline6":
          return Theme.of(context).textTheme.headline6;
        case "bodyText2":
          return Theme.of(context).textTheme.bodyText2;
        case "bodyText_15":
          return Theme.of(context).textTheme.bodyText2.copyWith(fontSize: 15.0);
        case "bodyText1":
          return Theme.of(context).textTheme.bodyText1;
        case "caption":
          return Theme.of(context).textTheme.caption;
        case "overline":
          return Theme.of(context).textTheme.overline;
        case "button":
          return Theme.of(context).textTheme.button;
        default :
          return TextStyle();
      }
    }

    return Column(
      mainAxisAlignment: MainAxisAlignment.center,
      crossAxisAlignment: CrossAxisAlignment.start,
      children: <Widget>[
        Stack(
          children: <Widget>[
            Text(!hidden ? text : (text.substring(0, text.length > widget.maxLength ? widget.maxLength : text.length)),
              textAlign: widget.textAlign,
              overflow: widget.maxLines!=null ? ((widget.maxLines > 1) ? TextOverflow.fade : TextOverflow.ellipsis) : null,
              maxLines: widget.maxLines ?? null,
              style: widget.style != null ? _getFontStyle().copyWith(
                fontStyle: widget.italic ? FontStyle.italic : null,
                color: widget.color!=null ? widget.color : null,
                fontWeight: _getFontWeight(),
              ) : TextStyle(
                fontStyle: widget.italic ? FontStyle.italic : null,
                color: widget.color!=null ? widget.color : Colors.black,
                fontSize: _getFontSize(),
                letterSpacing: widget.variant=="overline" ? 1.5 : null,
                fontWeight: _getFontWeight(),
              )
            ),
            if (widget.readMore && text.length > widget.maxLength && hidden)
            Positioned(
              bottom: 0,
              left: 0,
              right: 0,
              child: Container(
                decoration: BoxDecoration(
                  gradient: LinearGradient(
                    colors: [
                      Theme.of(context).backgroundColor,
                      Theme.of(context).backgroundColor.withOpacity(0),
                    ],
                    begin: Alignment.bottomCenter,
                    end: Alignment.topCenter
                  )
                ),
                height: 30,
              ),
            )
          ],
        ),
        if (widget.allowExpand && widget.readMore && text.length > widget.maxLength)
          Padding(
            padding: EdgeInsets.only(top: 8.0, right: 8.0, bottom: 8.0),
            child: InkWell(
              onTap: () {
                setState(() {
                  hidden=!hidden;
                });
              },
              child: Text(hidden ? "Read More" : "Read less",
                style: _getFontStyle().copyWith(
                  color: HexColor('#FF0000'),
                  fontWeight: FontWeight.w800,
                  fontFamily: "WorkSans"
                )
              ),
            ),
          ),
      ],
    );
  }
}