How to implement a color picker for macOS

Question

I need to implement a simpler version of Digital Color Meter, that means just a color picker of the current state of my screen.

I do not need any preview, or advanced controls, as Digital Color Meter does. All I need instead is to get the color of the selected pixel. in the clipboard.

Could you give me a hint about how could I implement something like this in macOS?

Answer 1

You don't need to, those lovely guys at Apple have done it for you. Just start the Color Picker, let the user choose a colour and it will be returned to your bash script.

So, the code looks like this in the Terminal or a bash script:

osascript -e "set theColor to choose color default color {0,0,0}"

The user must (probably) click the pipette just above the Cancel button, and click a pixel on the screen then click OK. The RGB returned is in the range 0..65535 for Red, Green and Blue.

As regards putting those RGB values on the Clipboard:

osascript <<EOF
set chosen to (choose color default color {65535, 65535, 65535})
set AppleScript's text item delimiters to ","
set the clipboard to chosen as string
EOF

That will give you something like this on the clipboard:

12000,37456,0

If you prefer something like this on the clipboard:

rgb(64633,1408,8371)

You can use:

osascript <<EOF
set chosen to (choose color default color {65535, 65535, 65535})
set col to "rgb(" & item 1 of chosen & "," & item 2 of chosen & "," &item 3 of chosen & ")"
set the clipboard to col
EOF