Q: How To Execute Javascript In A Chrome Tab

[muescha]

I like to know some ideas and some hints in which direction I can dig to find a solution for this

given:

• I have a Hammerspoon script to control video stop/pause - I do this sending keystrokes to an app - for example space to pause a video
• Sometimes it not only stop the video - instead it also execute the scroll the page which is also assigned to space in chrome

what i like to do:

• I like to find a way to select the player div in a website so that my kontrol keys are executed in scope of the (then) selected player

bonus:

• i can direct call some javascript functions of some injected players which are assigned to buttons and player controls

[megalithic]

Not sure if this fully solves it, but you can, with JXA, select a tab and do something in that tab with JS, so basically at that point, you're in the window context of that page:

https://github.com/megalithic/dotfiles/blob/main/config/hammerspoon/lib/browser.lua#L40-L57

[muescha]

thanks for the idea - but it seems that with JXA it is only possible to control some apps but I can not go deep into the window context?

[muescha]

but maybe you are right - it can be possible if i see this code snippet:

const tab = Application('Google Chrome').windows[0].activeTab()
tab.execute({
  javascript: 'document.querySelector("#dns-view-clear-cache").click()'
})

https://github.com/JXA-Cookbook/JXA-Cookbook/wiki/Safari-and-Chrome#clear-chromes-dns-cache

execute v : Execute a piece of javascript.
   execute specifier : The tab to execute the command in.
      javascript text : The javascript code to execute.
          → any

sources:

• https://www.macstories.net/tutorials/getting-started-with-javascript-for-automation-on-yosemite/
• https://hackmag.com/coding/getting-to-grips-with-javascript-automation-for-os-x/
• https://stackoverflow.com/questions/55949657/getting-values-from-inner-functions-of-current-webpage-in-chrome-via-jxa-appl