get-size.js

/*!
 * getSize v1.1.7
 * measure size of elements
 * MIT license
 */

/*jshint browser: true, strict: true, undef: true, unused: true */
/*global define: false, exports: false, require: false, module: false */

( function( window, undefined ) {

'use strict';

// -------------------------- helpers -------------------------- //

var getComputedStyle = window.getComputedStyle;
var getStyle = getComputedStyle ?
  function( elem ) {
    return getComputedStyle( elem, null );
  } :
  function( elem ) {
    return elem.currentStyle;
  };

// get a number from a string, not a percentage
function getStyleSize( value ) {
  var num = parseFloat( value );
  // not a percent like '100%', and a number
  var isValid = value.indexOf('%') === -1 && !isNaN( num );
  return isValid && num;
}

// -------------------------- measurements -------------------------- //

var measurements = [
  'paddingLeft',
  'paddingRight',
  'paddingTop',
  'paddingBottom',
  'marginLeft',
  'marginRight',
  'marginTop',
  'marginBottom',
  'borderLeftWidth',
  'borderRightWidth',
  'borderTopWidth',
  'borderBottomWidth'
];

function getZeroSize() {
  var size = {
    width: 0,
    height: 0,
    innerWidth: 0,
    innerHeight: 0,
    outerWidth: 0,
    outerHeight: 0
  };
  for ( var i=0, len = measurements.length; i < len; i++ ) {
    var measurement = measurements[i];
    size[ measurement ] = 0;
  }
  return size;
}



function defineGetSize( getStyleProperty ) {

// -------------------------- box sizing -------------------------- //

var boxSizingProp = getStyleProperty('boxSizing');
var isBoxSizeOuter;

/**
 * WebKit measures the outer-width on style.width on border-box elems
 * IE & Firefox measures the inner-width
 */
( function() {
  if ( !boxSizingProp ) {
    return;
  }

  var div = document.createElement('div');
  div.style.width = '200px';
  div.style.padding = '1px 2px 3px 4px';
  div.style.borderStyle = 'solid';
  div.style.borderWidth = '1px 2px 3px 4px';
  div.style[ boxSizingProp ] = 'border-box';

  var body = document.body || document.documentElement;
  body.appendChild( div );
  var style = getStyle( div );

  isBoxSizeOuter = getStyleSize( style.width ) === 200;
  body.removeChild( div );
})();


// -------------------------- getSize -------------------------- //

function getSize( elem ) {
  // use querySeletor if elem is string
  if ( typeof elem === 'string' ) {
    elem = document.querySelector( elem );
  }

  // do not proceed on non-objects
  if ( !elem || typeof elem !== 'object' || !elem.nodeType ) {
    return;
  }

  var style = getStyle( elem );

  // if hidden, everything is 0
  if ( style.display === 'none' ) {
    return getZeroSize();
  }

  var size = {};
  size.width = elem.offsetWidth;
  size.height = elem.offsetHeight;

  var isBorderBox = size.isBorderBox = !!( boxSizingProp &&
    style[ boxSizingProp ] && style[ boxSizingProp ] === 'border-box' );

  // get all measurements
  for ( var i=0, len = measurements.length; i < len; i++ ) {
    var measurement = measurements[i];
    var value = style[ measurement ];
    value = mungeNonPixel( elem, value );
    var num = parseFloat( value );
    // any 'auto', 'medium' value will be 0
    size[ measurement ] = !isNaN( num ) ? num : 0;
  }

  var paddingWidth = size.paddingLeft + size.paddingRight;
  var paddingHeight = size.paddingTop + size.paddingBottom;
  var marginWidth = size.marginLeft + size.marginRight;
  var marginHeight = size.marginTop + size.marginBottom;
  var borderWidth = size.borderLeftWidth + size.borderRightWidth;
  var borderHeight = size.borderTopWidth + size.borderBottomWidth;

  var isBorderBoxSizeOuter = isBorderBox && isBoxSizeOuter;

  // overwrite width and height if we can get it from style
  var styleWidth = getStyleSize( style.width );
  if ( styleWidth !== false ) {
    size.width = styleWidth +
      // add padding and border unless it's already including it
      ( isBorderBoxSizeOuter ? 0 : paddingWidth + borderWidth );
  }

  var styleHeight = getStyleSize( style.height );
  if ( styleHeight !== false ) {
    size.height = styleHeight +
      // add padding and border unless it's already including it
      ( isBorderBoxSizeOuter ? 0 : paddingHeight + borderHeight );
  }

  size.innerWidth = size.width - ( paddingWidth + borderWidth );
  size.innerHeight = size.height - ( paddingHeight + borderHeight );

  size.outerWidth = size.width + marginWidth;
  size.outerHeight = size.height + marginHeight;

  return size;
}

// IE8 returns percent values, not pixels
// taken from jQuery's curCSS
function mungeNonPixel( elem, value ) {
  // IE8 and has percent value
  if ( getComputedStyle || value.indexOf('%') === -1 ) {
    return value;
  }
  var style = elem.style;
  // Remember the original values
  var left = style.left;
  var rs = elem.runtimeStyle;
  var rsLeft = rs && rs.left;

  // Put in the new values to get a computed value out
  if ( rsLeft ) {
    rs.left = elem.currentStyle.left;
  }
  style.left = value;
  value = style.pixelLeft;

  // Revert the changed values
  style.left = left;
  if ( rsLeft ) {
    rs.left = rsLeft;
  }

  return value;
}

return getSize;

}

// transport
if ( typeof define === 'function' && define.amd ) {
  // AMD for RequireJS
  define( [ 'get-style-property/get-style-property' ], defineGetSize );
} else if ( typeof exports === 'object' ) {
  // CommonJS for Component
  module.exports = defineGetSize( require('get-style-property') );
} else {
  // browser global
  window.getSize = defineGetSize( window.getStyleProperty );
}

})( window );