add gripSizeActive property

[wangsoso]

library split_view;

import 'dart:collection'; import 'dart:math';

import 'package:flutter/material.dart'; import 'package:flutter/rendering.dart'; import 'package:flutter/widgets.dart';

/// A SplitView class. class SplitView extends StatefulWidget { static const Color defaultGripColor = Colors.grey; static const double defaultGripSizeActive = 6; static const Color defaultGripColorActive = Color.fromARGB(0xff, 0x66, 0x66, 0x66); static const double defaultGripSize = 12.0; static const double _weightLimit = 0.01;

final List children;

/// Controls the views being splitted. final SplitViewController? controller;

/// The [viewMode] specifies how to arrange views. final SplitViewMode viewMode;

/// The grip size. final double gripSize;

/// The Active grip size. final double gripSizeActive;

/// Grip color. final Color gripColor;

/// Active grip color. final Color gripColorActive;

/// Called when the user moves the grip. final ValueChanged<UnmodifiableListView<double?>>? onWeightChanged;

/// Grip indicator. final Widget? indicator;

/// Grip indicator for active state. final Widget? activeIndicator;

/// Creates a [SplitView]. SplitView({ Key? key, required this.children, required this.viewMode, this.gripSize = defaultGripSize, this.controller, this.gripColor = defaultGripColor, this.gripColorActive = defaultGripColorActive, this.gripSizeActive = defaultGripSizeActive, this.onWeightChanged, this.indicator, this.activeIndicator, }) : super(key: key);

@override State createState() => _SplitViewState(); }

class _SplitViewState extends State { late SplitViewController _controller; late Color _gripColor; late double _gripSize; bool _dragging = false; int _activeIndex = -1;

late double _startWeight1; late double _startWeight2; late double _startSize; late Offset _startDragPos;

@override void initState() { super.initState(); _gripSize = widget.gripSize; _controller = widget.controller != null ? widget.controller! : SplitViewController(); }

@override void didChangeDependencies() { super.didChangeDependencies();

_gripColor = widget.gripColor;
_gripSize = widget.gripSize;

}

@override Widget build(BuildContext context) { return LayoutBuilder( builder: (context, constraints) { _controller._init(widget.children.length); if (widget.viewMode == SplitViewMode.Vertical) { return _buildVerticalView( context, constraints, _controller.weights, _controller.limits); } else { return _buildHorizontalView( context, constraints, _controller.weights); } }, ); }

Stack _buildVerticalView(BuildContext context, BoxConstraints constraints, List<double?> weights, List<WeightLimit?> limits) { double viewsHeight = constraints.maxHeight - (_gripSize * (widget.children.length - 1)); double top = 0;

var children = <Widget>[];
for (int i = 0; i < widget.children.length; i++) {
  double weight = weights[i] ?? 0.1;
  var child = widget.children[i];
  children.add(Positioned(
    top: top,
    height: viewsHeight * weight,
    left: 0,
    right: 0,
    child: child,
  ));
  top += (viewsHeight * weight);
  if (i != widget.children.length - 1) {
    children.add(Positioned(
      top: top,
      height: _gripSize,
      left: 0,
      right: 0,
      child: MouseRegion(
        cursor: SystemMouseCursors.resizeRow,
        onEnter: (event) {
          setState(() {
            _activeIndex = i;
            _gripColor = widget.gripColorActive;
            _gripSize = widget.gripSizeActive;
          });
        },
        onExit: (_) {
          if (_dragging == false) {
            _activeIndex = -1;
            setState(() {
              _gripColor = widget.gripColor;
              _gripSize = widget.gripSize;
            });
          }
        },
        child: GestureDetector(
          behavior: HitTestBehavior.translucent,
          onVerticalDragDown: (details) {
            _dragging = true;
            _activeIndex = i;
            _gripColor = widget.gripColorActive;
            _gripSize = widget.gripSizeActive;
            _startDragPos =
                _getLocalPosition(context, details.globalPosition);
            _startWeight1 = _controller.weights[i]!;
            _startWeight2 = _controller.weights[i + 1]!;
            _startSize = viewsHeight * _startWeight1;
          },
          onVerticalDragEnd: (details) {
            _dragging = false;
            _activeIndex = -1;
            setState(() {
              _gripColor = widget.gripColor;
              _gripSize = widget.gripSize;
            });
          },
          onVerticalDragUpdate: (detail) {
            final pos = _getLocalPosition(context, detail.globalPosition);
            var diff = pos.dy - _startDragPos.dy;
            _changeWeights(diff, viewsHeight, i);
          },
          child: Container(
            color: _activeIndex == i ? _gripColor : widget.gripColor,
            alignment: Alignment.center,
            child: _activeIndex == i
                ? widget.activeIndicator != null
                    ? widget.activeIndicator
                    : widget.indicator
                : widget.indicator,
          ),
        ),
      ),
    ));
    top += _gripSize;
  }
}

return Stack(
  children: children,
);

}

Widget _buildHorizontalView( BuildContext context, BoxConstraints constraints, List<double?> weights) { double viewsWidth = constraints.maxWidth - (_gripSize * (widget.children.length - 1)); double left = 0;

var children = <Widget>[];
for (int i = 0; i < widget.children.length; i++) {
  double weight = weights[i] ?? 0.1;
  var child = widget.children[i];
  children.add(Positioned(
    left: left,
    width: viewsWidth * weight,
    top: 0,
    bottom: 0,
    child: child,
  ));
  left += (viewsWidth * weight);
  if (i != widget.children.length - 1) {
    children.add(Positioned(
      left: left,
      width: _gripSize,
      top: 0,
      bottom: 0,
      child: MouseRegion(
        cursor: SystemMouseCursors.resizeColumn,
        onEnter: (event) {
          setState(() {
            _gripColor = widget.gripColorActive;
            _activeIndex = i;
            _gripSize = widget.gripSizeActive;
          });
        },
        onExit: (_) {
          if (_dragging == false) {
            _activeIndex = -1;
            setState(() {
              _gripColor = widget.gripColor;
              _gripSize = widget.gripSize;
            });
          }
        },
        child: GestureDetector(
          behavior: HitTestBehavior.translucent,
          onHorizontalDragDown: (details) {
            _dragging = true;
            _activeIndex = i;
            _gripColor = widget.gripColorActive;
            _gripSize = widget.gripSizeActive;
            _startDragPos =
                _getLocalPosition(context, details.globalPosition);
            _startWeight1 = _controller.weights[i]!;
            _startWeight2 = _controller.weights[i + 1]!;
            _startSize = viewsWidth * _startWeight1;
          },
          onHorizontalDragEnd: (details) {
            _dragging = false;
            _activeIndex = -1;
            setState(() {
              _gripColor = widget.gripColor;
              _gripSize = widget.gripSize;
            });
          },
          onHorizontalDragUpdate: (detail) {
            final pos = _getLocalPosition(context, detail.globalPosition);
            var diff = pos.dx - _startDragPos.dx;
            _changeWeights(diff, viewsWidth, i);
          },
          child: Container(
            color: _activeIndex == i ? _gripColor : widget.gripColor,
            alignment: Alignment.center,
            child: _activeIndex == i
                ? widget.activeIndicator != null
                    ? widget.activeIndicator
                    : widget.indicator
                : widget.indicator,
          ),
        ),
      ),
    ));
    left += _gripSize;
  }
}

return Stack(
  children: children,
);

}

void _changeWeights(double diff, double size, int index) { var newWeight1 = (_startSize + diff) / size; newWeight1 = _adjustWeight(newWeight1, _controller.limits[index]); if (_controller.limits[index] != null) { if (_controller.limits[index]!.min != null) { newWeight1 = max(newWeight1, _controller.limits[index]!.min!); } if (_controller.limits[index]!.max != null) { newWeight1 = min(newWeight1, _controller.limits[index]!.max!); } } var newWeight2 = _startWeight1 + _startWeight2 - newWeight1; if (_controller.limits[index + 1] != null) { if (_controller.limits[index + 1]!.min != null) { newWeight2 = max(newWeight2, _controller.limits[index + 1]!.min!); } if (_controller.limits[index + 1]!.max != null) { newWeight2 = min(newWeight2, _controller.limits[index + 1]!.max!); } newWeight1 = _startWeight1 + _startWeight2 - newWeight2; } setState(() { _controller._weights[index] = newWeight1; _controller._weights[index + 1] = newWeight2; });

if (widget.onWeightChanged != null) {
  widget.onWeightChanged!(_controller.weights);
}

}

Offset _getLocalPosition(BuildContext context, Offset pos) { var container = context.findRenderObject() as RenderBox; return container.globalToLocal(pos); }

double _adjustWeight(double weight, WeightLimit? limit) { var w = min(weight, _startWeight1 + _startWeight2 - SplitView._weightLimit); w = max(w, SplitView._weightLimit); return w; } }

/// Controller for [Splitview] class SplitViewController { /// Specifies the weight of each views. UnmodifiableListView<double?> get weights => UnmodifiableListView(_weights);

/// Specifies the limits of each views. UnmodifiableListView<WeightLimit?> get limits => UnmodifiableListView(_limits);

List<double?> _weights; List<WeightLimit?> _limits;

SplitViewController._(this._weights, this._limits);

/// Creates a [SplitViewController] /// /// The [weights] specifies the ratio in the view. The sum of the [weights] cannot exceed 1. factory SplitViewController( {List<double?>? weights, List<WeightLimit?>? limits}) { if (weights == null) { weights = List.empty(growable: true); } if (limits == null) { limits = List.empty(growable: true); } return SplitViewController._(weights, limits); }

void _init(int length) { if (_weights.length < length) { _weights.length = length; } if (_limits.length < length) { _limits.length = length; } int nullCnt = _weights.where((element) => element == null).length; double weightSum = 0.0; _weights.forEach((weight) { weightSum += weight ?? 0; }); double weightRemain = 1.0 - weightSum; double calcWeight = weightRemain / nullCnt; for (int i = 0; i < _weights.length; i++) { if (_weights[i] == null) { _weights[i] = calcWeight; } } } }

/// A WeightLimit class. class WeightLimit { /// Minimal weight limit. final double? min;

/// Maximum weight limit. final double? max;

WeightLimit({this.min, this.max}); }

/// A SplitIndicator class. class SplitIndicator extends StatelessWidget { /// The [viewMode] specifies how to arrange views. final SplitViewMode viewMode;

/// Specifies true when it is used in the active state. final bool isActive;

/// Specified indicator color. final Color color;

const SplitIndicator({ required this.viewMode, this.isActive = false, this.color = Colors.white, });

@override Widget build(BuildContext context) { return SizedBox.expand( child: CustomPaint( painter: _SplitIndicatorPainter( viewMode: this.viewMode, isActive: this.isActive, color: this.color, ), ), ); } }

class _SplitIndicatorPainter extends CustomPainter { final SplitViewMode viewMode; final bool isActive; final Color color;

static const double DEFAULT_STROKE_WIDTH_RATIO = 0.1; static const double ACTIVE_STROKE_WIDTH_RATIO = 0.2; static const double STROKE_LENGTH = 0.15;

_SplitIndicatorPainter({ required this.viewMode, required this.isActive, required this.color, });

@override void paint(Canvas canvas, Size size) { Paint paint = Paint()..color = this.color; double x1, x2, y1, y2; double strokeWidthRatio = this.isActive ? ACTIVE_STROKE_WIDTH_RATIO : DEFAULT_STROKE_WIDTH_RATIO; if (this.viewMode == SplitViewMode.Horizontal) { x1 = x2 = size.width / 2; y1 = size.height (1 - STROKE_LENGTH) / 2; y2 = y1 + size.height STROKE_LENGTH; paint.strokeWidth = size.width strokeWidthRatio; paint.strokeCap = StrokeCap.round; } else { x1 = size.width (1 - STROKE_LENGTH) / 2; x2 = x1 + size.width STROKE_LENGTH; y1 = y2 = size.height / 2; paint.strokeWidth = size.height strokeWidthRatio; paint.strokeCap = StrokeCap.round; } canvas.drawLine(Offset(x1, y1), Offset(x2, y2), paint); }

@override bool shouldRepaint(covariant CustomPainter oldDelegate) { return true; } }

/// Arranges view order. enum SplitViewMode { /// Arranges vertically. Vertical,

/// Arranges horizontally. Horizontal, }