使用setInterval模拟setTimeout不适用于嵌套

问题描述

我为Chrome编写扩展程序。当背景页面不活动时，我需要运行延迟的任务。原因setTimeout在后台选项卡中不起作用，我尝试使用setInterval模拟setTimeout，如下面的代码（位于内容脚本中）：

  code> not displayed？
解决方案
您显然使用 runtime.getBackgroundPage 来代替。新的方法是异步的，因此它可以在返回之前根据需要启动事件页面。
 
 
  
  
I write extension for Chrome. And I need run delayed tasks when background page inactive. Cause setTimeout not working in background tabs, I try emulate setTimeout with setInterval, like code below (located in content script):
window.timings = [];

function set_timeout(func, time){
  var now = new Date() / 1;
  window.timings.push({
    func: func,
    time: time + now
  });
}

function tick(){
  var now = new Date() / 1;
  window.timings = window.timings.filter(function(delay_obj){
    if (now > delay_obj.time){
      delay_obj.func.call();
      return false;
    } else {
      return true;
    }
  });
}

$(function() {
  setInterval(tick, 1000);
  // some code
});
And it don't work when set_interval call in delay function:
set_timeout(function(){
  console.log('func1');
}, 2000);

set_timeout(function(){
  console.log('func2');

  set_timeout(function(){
    console.log('func3');
  }, 3000);

}, 3000);
Output:
func1
func2
Why func3 not displayed?
 解决方案 
You're apparently using an event page declared with "persistent": false in manifest.json, it is unloaded after 5 seconds of inactivity. The linked documentation says to use chrome.alarms API.
In case the alarm should be set for a period around 5 seconds:
Don't use the event page, switch to "persistent": true in manifest.json.
In case the alarm should be set for a period much larger than 5 seconds:
manifest.json:
"permissions": ["alarms"],
background script:
chrome.alarms.create("MyInterval1", {when: Date.now() + 30*1000});

chrome.alarms.onAlarm.addListener(function(alarm) {
    if (alarm.name == "MyInterval1") {
        console.log("Yay!");
        chrome.alarms.create("MyInterval1", {when: Date.now() + 30*1000});
    }
});
Also note:
                        
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