iOS Remote control for external monitor

iOS Remote control for external monitor is made to remotely control the external monitor connected to the computer.

Motivation: I use my 4K monitor as bedroom TV and as a part of my software development ansamble. It has Chromecast connected on HDMI port and DisplayPort connecting to MacBook Pro. When done watching Netflix, HBO, ... I don't feel like getting up from my bed to push Off button on the monitor since streaming is all done through the iPhone or iPad.

This setup was only tested on MacOS Catalina 10.15.2, MacBook Pro (15-inch, 2016) with Intel graphics and external monitor ViewSonic VP3268-4K PRO 32" 4K Monitor.

The iOS app is built for iOS 13.

Components

Server

The server component is written in GO language and it's using DDC monitor controls for Mac OSX command line

DDC/CI

DDC/CI protocol implementation for MacOS X is taken kfix repository DDC monitor controls for Mac OSX command line

iOS APP

iOS App is written in Swift 5 and target iOS 13.0

Install

• install XCode
• figure out if your Mac is using an Intel, Nvidia or AMD gpu
• Install GO

Run build script (provide either intel,nvidia or gpu argument). Example:

./build.sh intel

Run

Start the server:

./start.sh

Validate that the server is running, open browser and enter URL: http://localhost:7800/monitors

You should see JSON response as an empty array or if you have an external display connected there should be monitor in the list.

Start server on macOS X start

Modify daemon startup plist with the path to your start.sh script

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>EnvironmentVariables</key>
    <dict>
      <key>PATH</key>
      <string>/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin:</string>
    </dict>
    <key>Label</key>
    <string>com.monitorcontrol</string>
    <key>Program</key>
    <string>/Users/igor/GO/workspace/monitorcontrol/start.sh</string>
    <key>RunAtLoad</key>
    <true/>
    <key>KeepAlive</key>
    <false/>
    <key>LaunchOnlyOnce</key>
    <true/>
    <key>StandardOutPath</key>
    <string>/tmp/startup.stdout</string>
    <key>StandardErrorPath</key>
    <string>/tmp/startup.stderr</string>
    <key>UserName</key>
    <string>igor</string>
    <key>GroupName</key>
    <string>admin</string>
    <key>InitGroups</key>
    <true/>
  </dict>
</plist>

Copy file to cp com.monitorontrol.plist /Library/LaunchDaemons/

Load the launchd startup

sudo launchctl load -w /Library/LaunchDaemons/com.monitorcontrol.plist

-w flag permanently removes the plist from the Launch Daemon

sudo launchctl unload -w /Library/LaunchDaemons/com.monitorcontrol.plist

Once a script is added onto the Launch Daemon it will auto-start even if the user runs the following command

You can stop the launchctl process by

sudo launchctl stop /Library/LaunchDaemons/com.monitorcontrol.plist You can start the launchctl process by

sudo launchctl start -w /Library/LaunchDaemons/com.monitorcontrol.plist

Validate that Daemon is running

Open browser and visit this url: http://localhost:7800/monitors

Result should display an empty list if currently you don't have an external monitor connected or an external monitors' name