resources/file_manager/slideshow.html

<!DOCTYPE HTML>
<html i18n-values="dir:textdirection;">
<head>
<meta charset="utf-8">
<title>Slideshow</title>
<style>

body {
  overflow: hidden;
  background: black;
}

#glow {
  left: 0;
  right: 0;
  bottom: 30px;
  height: 8px;
  opacity: .4;
  position: absolute;
  background: -webkit-linear-gradient(transparent, white);
}

#main {
  position: absolute;
  left: 0;
  right:0;
  top: 0;
  bottom: 30px;
  overflow: hidden;
}

#playercontrols {
  bottom: 0;
  left: 0;
  z-index: 999;
  height: 30px;
  opacity: .9;
  right: 0;
  align:center;
  -webkit-box-align: center;
  -webkit-box-pack: center;
  display: -webkit-box;
  position: absolute;
  background: -webkit-linear-gradient(#323232, #070707);
}

#prevbutton > div {
  background: url('chrome://resources/images/mediaplayer_prev.png');
  background-repeat: no-repeat;
  background-position: 4px 8px;
  width: 100%;
  height: 30px;
  z-index: 9999;
}

.currentpicture {
  width: 100%;
  height: 100%;
  position: absolute;
  top: 0;
  -webkit-transition-property: left;
  -webkit-transition-duration: 1s;
  display: -webkit-box;
  -webkit-box-align: center;
  -webkit-box-pack: center;
  pointer-events: none;
}

.comingfromleft {
  left: -100%;
}

.comingfromright {
  left: 100%;
}

#nextbutton > div {
  background: url('chrome://resources/images/mediaplayer_next.png');
  background-repeat: no-repeat;
  background-position: 4px 8px;
  width: 100%;
  height: 30px;
  z-index: 9999;
}

button {
  z-index: 9999;
  cursor: pointer;
  width: 28px;
  height: 30px;
  webkit-appearance: none;
  padding: 0;
  border: 0;
  background: transparent;
}

button:hover {
  background: -webkit-linear-gradient(#6a7eac, #000000);
}

</style>
<script src="chrome://resources/js/local_strings.js"></script>
<script src="chrome://resources/js/media_common.js"></script>
<script>

document.addEventListener('DOMContentLoaded', load);

document.onselectstart = function(e) {
  e.preventDefault();
};

function $(o) {
  return document.getElementById(o);
}

///////////////////////////////////////////////////////////////////////////////
// Document Functions:

var currentPicture = null;
var prevPicture = null;
var currentFileOffset = 0;
var filelist = [];
var moveRight = false;
var lastimg = null;

function loadedPicture() {
  if (prevPicture) {
    if (moveRight) {
      prevPicture.style.left = '-100%';
    } else {
      prevPicture.style.left = '100%';
    }
  }
  if (window.innerHeight < lastimg.height ||
      window.innerWidth < lastimg.width) {
     if (lastimg.width > lastimg.height) {
       lastimg.style.height = 'auto';
       lastimg.style.width = '100%';
     } else {
       lastimg.style.width = 'auto';
       lastimg.style.height = '100%';
     }
  }
  setTimeout(function() {
      currentPicture.style.left = '0';
   }, 10);
}

function transitionTo(filePath, fromTheRight) {
  if (currentPicture) {
    if (prevPicture) {
      $('main').removeChild(prevPicture);
    }
    prevPicture = currentPicture;
  }

  currentPicture = document.createElement('div');

  $('main').appendChild(currentPicture);
  if (fromTheRight) {
    currentPicture.className = 'currentpicture comingfromright';
  } else {
    currentPicture.className = 'currentpicture comingfromleft';
  }
  var image = document.createElement('img');
  lastimg = image;
  image.onload = loadedPicture;
  image.onerror = loadedPicture;
  image.src = filePath;
  currentPicture.appendChild(image);
  moveRight = fromTheRight;
}

function browseFileResult() {
  currentFileOffset = 0;
  if (filelist.length > 0) {
    transitionTo(filelist[currentFileOffset], true);
  }
}

function keyPressed(e) {
  // Left Pressed
  if (e.keyCode == 37) {
    if (currentFileOffset > 0) {
      currentFileOffset--;
      transitionTo(filelist[currentFileOffset], false);
    }
  }
  // Right Pressed
  if (e.keyCode == 39) {
    if (currentFileOffset < (filelist.length - 1)) {
      currentFileOffset++;
      transitionTo(filelist[currentFileOffset], true);
    }
  }
}

function load() {
  localStrings = new LocalStrings();

  var views = chrome.extension.getViews();
  for (var i = 0; i < views.length; i++) {
    if (views[i].g_slideshow_data) {
      filelist = views[i].g_slideshow_data;
      views[i].g_slideshow_data = null;
    }
  }

  browseFileResult();
}

function prevButtonClick() {
  if (currentFileOffset > 0) {
    currentFileOffset--;
    transitionTo(filelist[currentFileOffset], false);
  }
}

function nextButtonClick() {
  if (currentFileOffset < (filelist.length - 1)) {
    currentFileOffset++;
    transitionTo(filelist[currentFileOffset], true);
  }
}

</script>
<body onkeydown="keyPressed(event)">
<div id="main"></div>
<div id="glow"></div>
<div id="playercontrols">
  <button id="prevbutton" onclick="prevButtonClick()">
    <div></div>
  </button>
  <button id="nextbutton" onclick="nextButtonClick()">
    <div></div>
  </button>
</div>
</body>
</html>