Question

我是Chrome扩展编码的新手，而且是javascript的新手。扩展名为 page_action 类型。我正在尝试通过点击popup.html中的按钮向background.js发送一条简单的消息。我在这个网站上看到了类似的问题，但似乎没有任何效果。加载扩展是好的。请帮忙

/* __background.js__  */

function checkForValidUrl(tabId, changeInfo,tab){
console.log("Extension loaded");
chrome.pageAction.show(tabId);
}

function readMessage (request, sender, sendResponse){
alert("reached");
console.log(request.greeting);
sendRequest({farewell:"goodbye"});
}

chrome.extension.onRequest.addListener(readMessage);
chrome.tabs.onUpdated.addListener(checkForValidUrl);


 /* __manifest.json__  */
{
"name": "DemoExtension",
"version": "1.0",
"manifest_version": 2,
"background": {
    "scripts": [
    "jquery.js",
    "background.js"
    ]
},

"description": "demo extension to learn coding chrome extensions.",
"icons": {
    "16": "images/16x16.png",
    "48": "images/48x48.png",
    "128": "images/128x128.png"
},

"page_action": {
    "default_icon": {
        "19": "images/19x19.png",
        "38": "images/38x38.png"
    },
    "default_title": "Demo extension",
    "default_popup": "popup.html"
},

"options_page": "options.html",

"permissions": [
    "tabs",
    "storage",
    "http://*/*",
    "https://*/*"
]   
 }

-

__popup.html__
<!DOCTYPE HTML>
<html>
<head>
    <title>Demo extension</title>
    <script src="./popup.js"></script>
</head>
<body>
    <button id="clickMe">Add</button>   
</body>
</html>

-

__popup.js__
function sendMessageToExtn() {
alert("reached in popup");
chrome.extension.sendMessage({
    greeting : "hello" }, 
            function(response) { console.log(response.farewell);
});
}

document.getElementById('clickMe').addEventListener('click', function () {
sendMessageToExtn();

}）;

我现在收到错误未捕获TypeError：无法调用null（匿名函数）的方法'addEventListener'

有类似的question。

Answer 1

解决了这个问题。首先纳入@apsillers的建议。然后最后移动

`<script src="./popup.js"></script>

从头部开始，在按钮标签下方。

将简单消息从popup.html传递给background.js时没有任何操作

1 个答案: