Ad

Change DOM Content With Chrome Extension

I am building a Chrome extension. I am trying to get my app to communicate with each page in the extension and the page the user is viewing in the browser. I need to access the dom from the extension and then update it.

manifest.json 
popup.html
popup.js
background.js 
content.js

and the current page the user is viewing.

My goal is on page load modify the dom and show the user the new version of the page before they ever see it. in popup.js users are allowed to enter keywords into the popup. The keywords are saved to localStorage and while they view the web the keywords are censored out of their view by making the parent div of the keywords hidden if it is found on any pages they are viewing.

I need help getting each page to communicate and I think the way I am hiding the parent divs in popup.js won't work. I am confused on how to perform the action on the dom from the front.

Send the dom to the background.js Find keywords on the page and change their parent divs to hidden. push the dom back to the viewing page.

I think this line is saying if I match any url then run my app but I am not sure.

  "matches":    ["*://*/*"],

My manifest.json

{
 "name": "Wuno Zensoring",
  "version" : "1.0",
   "permissions": [
   "activeTab",
   "tabs",
   "storage"
   ],
  "description": "This extension will search the document file for keywords and hide their parent div.",
  "icons": {                   
    "19": "icon19.png",
    "38": "icon38.png",
    "48": "icon48.png",
    "128": "icon128.png"  
  },    
    "background": {
    "persistent": false,
    "scripts": ["jquery-1.11.3.min.js","background.js"]
  },
     "content_scripts": [{
        "matches":    ["*://*/*"],
        "js":         ["content.js"],
        "run_at": "document_end",
        "all_frames": true
    }],
     "web_accessible_resources": [
        "popup.js", "content.js"
        ],
  "browser_action": {
    "default_icon": "icon.png128",
    "default_popup": "popup.html",
    "default_icon": {                   
      "19": "icon19.png",
      "38": "icon38.png",
      "48": "icon48.png",
      "128": "icon128.png"        
  }
  },
     "manifest_version": 2
}

popup.html

<!doctype html>
<html>
  <head>
    <title>Wuno Zensorship</title>
    <script src="jquery-1.11.3.min.js"></script>
        <script src="popup.js"></script>
    <link rel="stylesheet" type="text/css" target="_blank" rel="nofollow noreferrer" target="_blank" rel="nofollow noreferrer" href="styles.css">
  </head>
  <body>
    <img src="icon48.png">

 <section>
<form id="form" action="#" method="POST">
<input id="description" name="description" type="text" />
<input id="add" type="submit" value="Add" />
<button id="clearChecked">Clear Checked Items</button>
<button id="clear">Clear All</button>
</form>
<div id="alert"></div>
<ul id="keyWords"></ul>
</body>
</html>

popup.js

   $(document).ready(function () {
localArray = [];

if (!localStorage.keyWords) {
  localStorage.setItem('keyWords', JSON.stringify(localArray));
}

loadKeyWords();

function loadKeyWords() {
    $('#keyWords').html('');
    localArray = JSON.parse(localStorage.getItem('keyWords'));
    for(var i = 0; i < localArray.length; i++) {
      $('#keyWords').prepend('<li><input class="check" name="check" type="checkbox">'+localArray[i]+'</li>'); 
        }
    }

$('#add').click( function() {
   var Description = $('#description').val();
  if($("#description").val() === '') {
    $('#alert').html("<strong>Warning!</strong> You left the to-do empty");
    $('#alert').fadeIn().delay(1000).fadeOut();
    return false;
   }
   $('#form')[0].reset();
   var keyWords = $('#keyWords').html();
   localArray.push(Description);
   localStorage.setItem('keyWords', JSON.stringify(localArray));
   loadKeyWords();
   return false;
});

$('#clear').click( function() {
window.localStorage.clear();
location.reload();
return false;
});

$('#clearChecked').click(function() {
  currentArray = [];
  $('.check').each(function() {
    var $curr = $(this);
    if (!$curr.is(':checked')) {
      var value = $curr.parent().text();
      currentArray.push(value);
      localStorage.setItem('keyWords', JSON.stringify(currentArray));
      loadKeyWords();
    } else {
      $curr.parent().remove();
    }
  });
});


// Update the relevant fields with the new data
function setDOMInfo(info) {
  $("div p:contains(localStorage.getItem('keyWords')).parent('div').hide()");
}

// Once the DOM is ready...
window.addEventListener('DOMContentLoaded', function () {
  // ...query for the active tab...
  chrome.tabs.query({
    active: true,
    currentWindow: true
  }, function (tabs) {
    // ...and send a request for the DOM info...
    chrome.tabs.sendMessage(
        tabs[0].id,
        {from: 'popup', subject: 'DOMInfo'},
        // ...also specifying a callback to be called 
        //    from the receiving end (content script)
        setDOMInfo);
  });
});


}); // End of document ready function

background.js

chrome.runtime.onMessage.addListener(function (msg, sender) {
  // First, validate the message's structure
  if ((msg.from === 'content') && (msg.subject === 'showPageAction')) {
    // Enable the page-action for the requesting tab
    chrome.pageAction.show(sender.tab.id);
  }
});

content.js

// Inform the background page that 
// this tab should have a page-action
chrome.runtime.sendMessage({
  from:    'content',
  subject: 'showPageAction'
});

// Listen for messages from the popup
chrome.runtime.onMessage.addListener(function (msg, sender, response) {
  // First, validate the message's structure
  if ((msg.from === 'popup') && (msg.subject === 'DOMInfo')) {
    // Collect the necessary data 
    // (For your specific requirements `document.querySelectorAll(...)`
    //  should be equivalent to jquery's `$(...)`)
    var domInfo = {
      total:   document.querySelectorAll('*').length,
      inputs:  document.querySelectorAll('input').length,
      buttons: document.querySelectorAll('button').length
    };

    // Directly respond to the sender (popup), 
    // through the specified callback */
    response(domInfo);
  }
});
Ad

Answer

You need to use this query to send data to DOM from the current tab being viewed.

    chrome.tabs.executeScript(null, {
        code: 'var config = ' + JSON.stringify(getKeywords)
    }, function() {
        chrome.tabs.executeScript(null, {file: 'custom.js'});
    });

and in the custom.js file you can write you function that you want to apply on the DOM element. like if you want to hide something than you need that query in custom.js. So if you wanted to use that example you would need to modify it according to your requirements.

var all = document.getElementsByTagName("div");
var searchValue=config.toString().split(',');
alert('Example:' + searchValue[0]);
for(j=0; j < searchValue.length; j++) {
for(i=0; i < all.length; i++) {
    if(all[i].innerHTML.indexOf(searchValue[j]) > -1){
    all[i].innerHTML = ""
    }
}
}
Ad
source: stackoverflow.com
Ad