我正在创建一个 Chrome 扩展程序，它将在标签上方绘制一个显示 Flash 内容的图像。我已经在我的“contentscript.js”文件中编写了内容脚本，它只是通过脚本标签将另一个脚本文件“backgroundscript.js”插入到页面的正文中。
该代码适用于少数具有 Flash 视频的网站，并在 Flash Player 窗口的正上方显示图像，但在其他网站上则不显示。同样在少数情况下，它会出现几分之一秒，然后消失。
下面是我的清单文件：
{
"name": "My First Chrome Extension",
"version": "1.0.0.0",
"description": "Tag videos from websites with a single click!",
"icons": { "16":"application_16.png","48":"application_48.png","128":"application_128.png" },
"homepage_url": "http://www.myurl.com",
"page_action":{
"default_icon":{
"19":"application_19.png",
"38":"application_38.png"
},
"default_title":"VDownloader browser plugin"
},
"content_scripts": [ { "js": [ "contentscript.js" ], "matches": [ "http://*/*" ], "run_at" : "document_end", "all_frames": true} ],
"plugins": [ { "path": "myplugin.dll", "public": true } ],
"manifest_version":2,
"minimum_chrome_version":"17",
"offline_enabled":true,
"permissions":["tabs","http://*/*", "https://*/*","contextMenus"],
"web_accessible_resources":["application.png","backgroundscript.js"]
}
我还通过插入“调试器”进行了检查；通过控制台进入我的脚本并监控代码执行；该脚本至少被添加到页面正文中一次。即使在没有显示图像按钮的情况下。
这是在不显示我的按钮的更高级网站上实施的某种 anit-XSS 控件吗？
我非常感谢您的帮助，因为过去几周我一直在努力克服这个问题，但没有成功:(
编辑：
请参阅下面的内容脚本：
var s = document.createElement('script');
s.src = chrome.extension.getURL("backgroundscript.js");
s.onload = function() {
this.parentNode.removeChild(this);
};
(document.head||document.documentElement).appendChild(s);
目标站点：
- 不显示按钮：http ://www.metacafe.com
- 显示按钮片刻：http ://www.dailymotion.com
- 正确显示按钮：http ://www.myreviewalarm.com
请看一下 backgroundscript.js 的内容：
var vdDelayTimer;
var vdUpdateInterval;
var playerButtons;
embedPlugin();
function embedPlugin() {
var embed = document.createElement('embed');
embed.setAttribute('type', 'application/x-myplugin');
embed.setAttribute('id', 'myplugin');
embed.setAttribute('style', 'width:1px;height:1px;position:absolute;left:0px;top:0px;');
if(document.body!=null)
{
document.body.appendChild(embed);
}
testPlugin();
}
function testPlugin() {
var plugin = document.getElementById('vdPlugin');
if (plugin != null) {
playerButtons = [];
vdDelayTimer = setTimeout("appendButtons()", 2000);
}
else {
window.alert('Plugin does not exist!');
}
}
function updateButtons() {
for (i = 0; i < playerButtons.length; i += 2) {
updateButtonLocation(playerButtons[i], playerButtons[i + 1]);
}
}
function updateButtonLocation(player, button) {
var playerX = getX(player);
var playerY = getY(player);
var buttonHeight = 38;
var buttonWidth = 196;
var buttonX = playerX + player.offsetWidth - buttonWidth - 12;
var buttonY = playerY - buttonHeight + 1;
button.setAttribute('style', 'background-image: url(http://myurl.com/img/browser-download-button.png); width:' + buttonWidth + 'px;height:' + buttonHeight + 'px;position:absolute;left:' + buttonX + 'px;top:' + buttonY + 'px; cursor:pointer; cursor:hand;');
}
function appendButtons() {
debugger;
var objectTags = document.getElementsByTagName('object');
for (var i = 0; i < objectTags.length; i++) {
var objectTag = objectTags[i];
if ((objectTag.hasAttribute('classid') && objectTag.getAttribute('classid') == 'clsid:D27CDB6E-AE6D-11cf-96B8-444553540000')
|| (objectTag.hasAttribute('type') && objectTag.getAttribute('type') == 'application/x-shockwave-flash')) {
if (objectTag.offsetWidth >= 320 && objectTag.offsetHeight >= 240)
createButton(objectTag, getX(objectTag), getY(objectTag), objectTag.offsetWidth);
}
}
var embedTags = document.getElementsByTagName('embed');
for (var i = 0; i < embedTags.length; i++) {
try {
var embedTag = embedTags[i];
if (embedTag.hasAttribute('type') && embedTag.getAttribute('type') == 'application/x-shockwave-flash') {
if (embedTag.offsetWidth >= 320 && embedTag.offsetHeight >= 240)
createButton(embedTag, getX(embedTag), getY(embedTag), embedTag.offsetWidth);
}
}
catch (err) { }
}
var videoTags = document.getElementsByTagName('video');
for (var i = 0; i < videoTags.length; i++) {
try {
var videoTag = videoTags[i];
if (videoTag.hasAttribute('src')) {
if (videoTag.offsetWidth >= 320 && videoTag.offsetHeight >= 240)
createButton(videoTag, getX(videoTag), getY(videoTag), videoTag.offsetWidth);
}
}
catch (err) { }
}
vdUpdateInterval = setInterval("updateButtons();", 500);
}
function createButton(videoTag, playerX, playerY, playerWidth) {
debugger;
var buttonHeight = 38;
var buttonWidth = 196;
var buttonX = playerX + playerWidth - buttonWidth - 12;
var buttonY = playerY - buttonHeight + 1;
var vdPlugin = document.getElementById('vdPlugin');
var strLocation = window.location.toString();
// if (isSupported(strLocation)) {
var downloadButton = document.createElement('img');
downloadButton.setAttribute('title', 'Tag this video');
downloadButton.setAttribute('src', 'http://myurl.com/img/browser-download-button.png');
downloadButton.setAttribute('style', 'background-image: url(http://myurl.com/img/browser-download-button.png); width:' + buttonWidth + 'px;height:' + buttonHeight + 'px;position:absolute;left:' + buttonX + 'px;top:' + buttonY + 'px; cursor:pointer;cursor:hand;z-index:2147483647;');
downloadButton.setAttribute('onclick', 'javascript:document.getElementById(\'vdPlugin\').downloadNow(window.location.href);');
downloadButton.setAttribute('oncontextmenu', 'javascript:return false;');
document.body.appendChild(downloadButton);
playerButtons.push(videoTag, downloadButton);
// }
}
function getY(oElement) {
var iReturnValue = 0;
while (oElement != null) {
iReturnValue += oElement.offsetTop;
oElement = oElement.offsetParent;
}
return iReturnValue;
}
function getX(oElement) {
var iReturnValue = 0;
while (oElement != null) {
iReturnValue += oElement.offsetLeft;
oElement = oElement.offsetParent;
}
return iReturnValue;
}
function isSupported(url) {
var regLen = supportedSites.length;
var regEx;
var res = false;
try {
for (var i = 0; i < regLen && res == false; i++) {
regEx = new RegExp(supportedSites[i], "i");
res = regEx.test(url);
}
}
catch (ex) {
}
return res;
}