Move client/{base, observable, layout, touch, util, view} to samples/ui_lib .

client/layout/SizingFunctions.dart

-// Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-
-// This file has classes representing the grid sizing functions
-
-/**
- * Represents the sizing function used for the min or max of a row or column.
- */
-// TODO(jmesserly): rename to GridSizing, or make internal
-class SizingFunction {
-  const SizingFunction();
-
-  bool get isContentSized() => isMinContentSized || isMaxContentSized;
-  bool get isMinContentSized() => false;
-  bool get isMaxContentSized() => false;
-  bool get isFraction() => false;
-
-  num resolveLength(num gridSize) => 0;
-
-  num get fractionValue() => 0;
-
-  // TODO(jmesserly): this is only needed because FixedSizing is mutable
-  SizingFunction clone() => this;
-}
-
-/**
- * Fixed size reprensents a length as defined by CSS3 Values spec.
- * Can also be a percentage of the Grid element's logical width (for columns)
- * or logical height (for rows). When the width or height of the Grid element
- * is undefined, the percentage is ignored and the Grid Track will be
- * auto-sized.
- */
-class FixedSizing extends SizingFunction {
-  final String units;
-  final num length;
-
-  // TODO(jmesserly): kind of ugly to have this mutable property here, but
-  // we need to correctly track whether we're content sized during a layout
-  bool _contentSized;
-
-  FixedSizing(this.length, [this.units = 'px'])
-    : super(),
-      _contentSized = false {
-    if (units != 'px' && units != '%') {
-      // TODO(jmesserly): support other unit types
-      throw new UnsupportedOperationException('Units other than px and %');
-    }
-  }
-
-  // TODO(jmesserly): this is only needed because of our mutable property
-  FixedSizing clone() => new FixedSizing(length, units);
-
-  bool get isMinContentSized() => _contentSized;
-
-  num resolveLength(num gridSize) {
-    if (units == '%') {
-      if (gridSize == null) {
-        // Use content size when the grid doesn't have an absolute size in this
-        // dimension
-        _contentSized = true;
-        return 0;
-      }
-      _contentSized = false;
-      return (length / 100) * gridSize;
-    } else {
-      return length;
-    }
-  }
-
-  String toString() => 'FixedSizing: ${length}${units} $_contentSized';
-}
-
-
-/**
- * Fraction is a non-negative floating-point number followed by 'fr'. Each
- * fraction value takes a share of the remaining space proportional to its
- * number.
- */
-class FractionSizing extends SizingFunction {
-  final num fractionValue;
-  FractionSizing(this.fractionValue) : super() {}
-
-  bool get isFraction() => true;
-
-  String toString() => 'FixedSizing: ${fractionValue}fr';
-}
-
-class MinContentSizing extends SizingFunction {
-  const MinContentSizing() : super();
-
-  bool get isMinContentSized() => true;
-
-  String toString() => 'MinContentSizing';
-}
-
-class MaxContentSizing extends SizingFunction {
-  const MaxContentSizing() : super();
-
-  bool get isMaxContentSized() { return true; }
-
-  String toString() => 'MaxContentSizing';
-}
-
-/** The min and max sizing functions for a track. */
-class TrackSizing {
-  /** The min sizing function for the track. */
-  final SizingFunction min;
-
-  /** The min sizing function for the track. */
-  final SizingFunction max;
-
-  const TrackSizing.auto()
-    : min = const MinContentSizing(),
-      max = const MaxContentSizing();
-
-  TrackSizing(this.min, this.max) {}
-
-  // TODO(jmesserly): this is only needed because FixedSizing is mutable
-  TrackSizing clone() => new TrackSizing(min.clone(), max.clone());
-}
-
-/** Represents a GridTrack breadth property. */
-// TODO(jmesserly): these classes could be replaced with reflection/mirrors
-interface _BreadthAccumulator {
-  void setSize(GridTrack t, num value);
-  num getSize(GridTrack t);
-
-  SizingFunction getSizingFunction(GridTrack t);
-}
-
-class _UsedBreadthAccumulator implements _BreadthAccumulator {
-  const _UsedBreadthAccumulator();
-
-  void setSize(GridTrack t, num value) { t.usedBreadth = value; }
-  num getSize(GridTrack t) => t.usedBreadth;
-
-  SizingFunction getSizingFunction(GridTrack t) => t.minSizing;
-}
-
-class _MaxBreadthAccumulator implements _BreadthAccumulator {
-  const _MaxBreadthAccumulator();
-
-  void setSize(GridTrack t, num value) { t.maxBreadth = value; }
-  num getSize(GridTrack t) => t.maxBreadth;
-
-  SizingFunction getSizingFunction(GridTrack t) => t.maxSizing;
-}
-