hexToRgba (hex) {
      if (hex === '' || hex === 'none') return { r: null, g: null, b: null, a: null }
      hex = this.validateHex(hex)
      let r = '00'; let g = '00'; let b = '00'; let a = '255'
      if (hex.length === 6) hex += 'ff'
      if (hex.length > 6) {
        r = hex.substring(0, 2)
        g = hex.substring(2, 4)
        b = hex.substring(4, 6)
        a = hex.substring(6, hex.length)
      } else {
        if (hex.length > 4) {
          r = hex.substring(4, hex.length)
          hex = hex.substring(0, 4)
        }
        if (hex.length > 2) {
          g = hex.substring(2, hex.length)
          hex = hex.substring(0, 2)
        }
        if (hex.length > 0) b = hex.substring(0, hex.length)
      }
      return {
        r: this.hexToInt(r), g: this.hexToInt(g), b: this.hexToInt(b), a: this.hexToInt(a)
      }
    }
@param {string} hex
@returns {module:jPicker.RGBA}