Method getCellHeight

src/gridstack.ts:857–885

* Gets the current cell height in pixels. This takes into account the unit type and converts to pixels if necessary. * * @param forcePixel if true, forces conversion to pixels even when cellHeight is specified in other units * @returns the cell height in pixels * * @example * const

(forcePixel = false)

   * const pixelHeight = grid.getCellHeight(true);
   */
  public getCellHeight(forcePixel = false): number {
    if (this.opts.cellHeight && this.opts.cellHeight !== 'auto' &&
      (!forcePixel || !this.opts.cellHeightUnit || this.opts.cellHeightUnit === 'px')) {
      return this.opts.cellHeight as number;
    }
    // do rem/em/cm/mm to px conversion
    if (this.opts.cellHeightUnit === 'rem') {
      return (this.opts.cellHeight as number) * parseFloat(getComputedStyle(document.documentElement).fontSize);
    }
    if (this.opts.cellHeightUnit === 'em') {
      return (this.opts.cellHeight as number) * parseFloat(getComputedStyle(this.el).fontSize);
    }
    if (this.opts.cellHeightUnit === 'cm') {
      // 1cm = 96px/2.54. See https://www.w3.org/TR/css-values-3/#absolute-lengths
      return (this.opts.cellHeight as number) * (96 / 2.54);
    }
    if (this.opts.cellHeightUnit === 'mm') {
      return (this.opts.cellHeight as number) * (96 / 2.54) / 10;
    }
    // else get first cell height
    const el = this.el.querySelector('.' + this.opts.itemClass) as HTMLElement;
    if (el) {
      const h = Utils.toNumber(el.getAttribute('gs-h')) || 1; // since we don't write 1 anymore
      return Math.round(el.offsetHeight / h);
    }
    // else do entire grid and # of rows (but doesn't work if min-height is the actual constrain)
    const rows = parseInt(this.el.getAttribute('gs-current-row'));
    return rows ? Math.round(this.el.getBoundingClientRect().height / rows) : this.opts.cellHeight as number;
  }

  /**
   * Update current cell height - see `GridStackOptions.cellHeight` for format by updating eh Browser CSS variable.