kmpdfkit_demo/lib/widgets/viewer/pdfbota/pdfoutline/cpdf_outline_page.dart

///
///  Copyright © 2014-2023 PDF Technologies, Inc. All Rights Reserved.
///
///  THIS SOURCE CODE AND ANY ACCOMPANYING DOCUMENTATION ARE PROTECTED BY INTERNATIONAL COPYRIGHT LAW
///  AND MAY NOT BE RESOLD OR REDISTRIBUTED. USAGE IS BOUND TO THE ComPDFKit LICENSE AGREEMENT.
///  UNAUTHORIZED REPRODUCTION OR DISTRIBUTION IS SUBJECT TO CIVIL AND CRIMINAL PENALTIES.
///  This notice may not be removed from this file.

import 'package:compdfkit_flutter/core/document/cpdf_document.dart';
import 'package:compdfkit_flutter/core/document/cpdf_outline_data.dart';
import 'package:flutter/material.dart';

import 'cpdf_outline_item.dart';

class CPDFOutlinePage extends StatefulWidget {
  final CPDFDocument document;

  const CPDFOutlinePage({Key? key, required this.document}) : super(key: key);

  @override
  State<CPDFOutlinePage> createState() => _CPDFOutlinePageState();
}

class _CPDFOutlinePageState extends State<CPDFOutlinePage> with AutomaticKeepAliveClientMixin
     {
  List<CPDFOutlineData> _outlineList = List.empty(growable: true);

  final globalKey = GlobalKey<AnimatedListState>();

  @override
  void initState() {
    super.initState();
    widget.document.getOutline().then((value) {
      setState(() {
        _outlineList = value;
      });
    });
  }

  @override
  Widget build(BuildContext context) {
    return ListView.builder(
        itemCount: _outlineList.length,
        itemBuilder: (context, index) {
          return CPDFOutlineItem(
            outlineData: _outlineList[index],
            onDisplayPageIndex: (pageIndex) {
              Navigator.pop(context, pageIndex);
            },
            onExpanded: (expanded) {
              setState(() {
                if (expanded) {
                  loopCollapseItem(_outlineList[index]);
                } else {
                  _outlineList[index].expanded = true;
                  _outlineList.insertAll(
                      index + 1, _outlineList[index].childOutline ?? []);
                }
              });
            },
          );
        });
  }

  @override
  bool get wantKeepAlive => true;

  void loopCollapseItem(CPDFOutlineData data) {
    data.expanded = false;
    data.childOutline?.forEach((element) {
      if (element.childOutline != null && element.childOutline!.isNotEmpty) {
        loopCollapseItem(element);
      }
      _outlineList.remove(element);
    });
  }
}