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

client/layout/GridTracks.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 tracks and grid template
-
-/**
- * The data structure representing the grid-rows or grid-columns
- * properties.
- */
-class GridTrackList {
-  /** The set of tracks defined in CSS via grid-rows and grid-columns */
-  final List<GridTrack> tracks;
-
-  /**
-   * Maps edge names to the corresponding track. Depending on whether the index
-   * is used as a start or end, it might be interpreted exclusively or
-   * inclusively.
-   */
-  final Map<String, int> lineNames;
-
-  GridTrackList(this.tracks, this.lineNames) {}
-}
-
-
-/** Represents a row or a column. */
-class GridTrack {
-  /**
-   * The start position of this track. Equal to the sum of previous track's
-   * usedBreadth.
-   */
-  num start;
-
-  /** The final computed breadth of this track. */
-  num usedBreadth;
-
-  // Fields used internally by the sizing algorithm
-  num maxBreadth;
-  num updatedBreadth;
-  num tempBreadth;
-
-  final TrackSizing sizing;
-
-  GridTrack(this.sizing) {}
-
-  /**
-   * Support for the feature that repeats rows and columns, e.g.
-   * [:grid-columns: 10px ("content" 250px 10px)[4]:]
-   */
-  GridTrack clone() => new GridTrack(sizing.clone());
-
-  /** The min sizing function for the track. */
-  SizingFunction get minSizing() => sizing.min;
-
-  /** The min sizing function for the track. */
-  SizingFunction get maxSizing() => sizing.max;
-
-  num get end() => start + usedBreadth;
-
-  bool get isFractional() => minSizing.isFraction || maxSizing.isFraction;
-}
-
-
-/** Represents the grid-row-align or grid-column-align. */
-class GridItemAlignment {
-  // TODO(jmesserly): should this be stored as an int for performance?
-  final String value;
-
-  // 'start' | 'end' | 'center' | 'stretch'
-  GridItemAlignment.fromString(String value)
-    : this.value = (value == null) ? 'stretch' : value {
-
-      switch (this.value) {
-      case 'start': case 'end': case 'center': case 'stretch':
-        break;
-      default:
-        throw new UnsupportedOperationException(
-            'invalid row/column alignment "$value"');
-    }
-  }
-
-  _GridLocation align(_GridLocation span, int size) {
-    switch (value) {
-      case 'start':
-        return new _GridLocation(span.start, size);
-      case 'end':
-        return new _GridLocation(span.end - size, size);
-      case 'center':
-        size = Math.min(size, span.length);
-        num center = span.start + span.length / 2;
-        num left = center - size / 2;
-        return new _GridLocation(left.round().toInt(), size);
-      case 'stretch':
-        return span;
-    }
-  }
-}
-
-
-/**
- * Represents a grid-template. Used in conjunction with a grid-cell to
- * place cells in the grid, without needing to specify the exact row/column.
- */
-class GridTemplate {
-  final Map<int, _GridTemplateRect> _rects;
-  final int _numRows;
-
-  GridTemplate(List<String> rows)
-    : _rects = new Map<int, _GridTemplateRect>(),
-      _numRows = rows.length {
-    _buildRects(rows);
-  }
-
-  /** Scans the template strings and computes bounds for each one. */
-  void _buildRects(List<String> templateRows) {
-    for (int r = 0; r < templateRows.length; r++) {
-      String row = templateRows[r];
-      for (int c = 0; c < row.length; c++) {
-        int cell = row.charCodeAt(c);
-        final rect = _rects[cell];
-        if (rect != null) {
-          rect.add(r + 1, c + 1);
-        } else {
-          _rects[cell] = new _GridTemplateRect(cell, r + 1, c + 1);
-        }
-      }
-    }
-
-    // Finally, check that each rectangle is valid (i.e. all spaces filled)
-    for (final rect in _rects.getValues()) {
-      rect.checkValid();
-    }
-  }
-
-  /**
-   * Looks up the given cell in the template, and returns the rect.
-   */
-  _GridTemplateRect lookupCell(String cell) {
-    if (cell.length != 1) {
-      throw new UnsupportedOperationException(
-          'grid-cell "$cell" must be a one character string');
-    }
-    final rect = _rects[cell.charCodeAt(0)];
-    if (rect == null) {
-      throw new UnsupportedOperationException(
-        'grid-cell "$cell" not found in parent\'s grid-template');
-    }
-    return rect;
-  }
-}
-
-/** Used by GridTemplate to track a single cell's bounds. */
-class _GridTemplateRect {
-  int row, column, rowSpan, columnSpan, _count, _char;
-  _GridTemplateRect(this._char, this.row, this.column)
-    : rowSpan = 1, columnSpan = 1, _count = 1 {}
-
-  void add(int r, int c) {
-    assert (r >= row && c >= column);
-    _count++;
-    rowSpan = Math.max(rowSpan, r - row + 1);
-    columnSpan = Math.max(columnSpan, c - column + 1);
-  }
-
-  void checkValid() {
-    int expected = rowSpan * columnSpan;
-    if (expected != _count) {
-      // TODO(jmesserly): not sure if we should throw here, due to CSS's
-      // permissiveness. At the moment we're noisy about errors.
-      String cell = new String.fromCharCodes([_char]);
-      throw new UnsupportedOperationException('grid-template "$cell"' +
-          ' is not square, expected $expected cells but got $_count');
-    }
-  }
-}
-
-
-/**
- * Used to return a row/column and span during parsing of grid-row and
- * grid-column during parsing.
- */
-class _GridLocation {
-  final int start, length;
-  _GridLocation(this.start, this.length) {}
-
-  int get end() => start + length;
-}