Chrome扩展程序-如何在每次加载页面时运行主脚本

时间:2018-08-14 17:22:14

标签: javascript google-chrome-extension

因此,我的主要内容脚本在刷新页面时运行,但是当我单击网页的新页面时,它不再运行;刷新页面时只有一次。我希望每次页面更改或URL更改时都重新运行。主要内容脚本中的主要功能称为“ runExtension()”

这是我的background.js

chrome.tabs.onUpdated.addListener( function (tabId, changeInfo, tab) {
  if (changeInfo.status == 'complete') {

    alert("LOADED");
    setTimeout(runExtension, 1000);

  }
})

这是我的manifest.json

{
	"manifest_version": 2, 
 	"name": "RateMyBull",
 	"description": "View professor ratings from RateMyProfessor when signing up for classes on the USF schedule planner", 
  	"version": "1.0",

	"permissions": ["https://usf.collegescheduler.com/*"],
	"background": {
    	"scripts":  ["background.js"]
  },

 	"content_scripts": [
		{
		"matches": ["https://usf.collegescheduler.com/*"],
		"js": ["RateMyBull.js", "jquery-3.3.1.min.js", "jquery-3.3.1.js"],
		"run_at": "document_idle",
	 	}
 	 ]
}
 这是主要脚本

setTimeout(runExtension, 1000);


function runExtension(){

		var tableElementNode = document.querySelectorAll(".section-detail-grid.table-bordered-wrap>tbody>tr>td>div");
		console.log(tableElementNode);


	 for (var i = 0; i < tableElementNode.length; i++) {
		if(tableElementNode[i].children.length < 1 && tableElementNode[i].innerText != "Not Assigned") {
			tableElementNode[i].className = "professor";
		}
	}
	var professorsArray = [];
	var professorElementNode = document.querySelectorAll(".professor");
	 for (var i = 0; i < professorElementNode.length; i++) {
			professorElementNode[i].id = i;
			var professorName = professorElementNode[i].innerText;
			professorName = professorName.trim();
			professorName = professorName.replace(/,/g, "");
			professorName = professorName.split([' ']);
			var firstName = professorName[1];
			var lastName = professorName[0];
			var professorObj = {
				first: firstName,
				last: lastName,
				ID: i
			};
			professorsArray[i] = professorObj;
			console.log(professorsArray[i].first);
	}
	alert("this just ran");
}
chrome.runtime.onMessage.addListener(function(msg, sender, sendResponse) {
    if (msg === 'url-update') {
        alert("TEST");
    }
});

1 个答案:

答案 0 :(得分:0)

Content scripts类似于RateMyBull.js在与后台页面(在but somewhat isolated from,一个网页上)完全不同的环境中运行。

如果您希望背景页面导致内容脚本中的代码运行,请使用message passing

根据您的情况,尝试将background.js更改为:

chrome.tabs.onUpdated.addListener( function (tabId, changeInfo, tab) {
  if (changeInfo.status == 'complete') {

    chrome.tabs.sendMessage(tab.id, {type: "runExtension"});

  }
})

然后在RateMyBull.js内容脚本中添加一个侦听器:

chrome.runtime.onMessage.addListener(
  function(request, sender, sendResponse) {
    if (request.type === "runExtension")
      runExtension();
  });

当然,网页可以通过多种方式“更改”。请参阅评论中引用的the question和相关答案wOxxOm,以获取有关检测各种类型变化的更多信息。