Where are SF-Symbols located?

Question

Become used SF-Symbols part of the bundle and become compiled to the executable file? Or are there only references and the actual icons are provided by the OS of the user?

Answer 1

The symbols are stored somewhere in the OS. Your app only contains "references" to them.

According to this post, the SF symbols in the iPhone simulator are located in:

/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/
Library/Developer/CoreSimulator/Profiles/Runtimes/iOS.simruntime/Contents/
Resources/RuntimeRoot/System/Library/PrivateFrameworks/SFSymbols.framework/
CoreGlyphs.bundle/Assets.car

Notice that this is inside "iOS.simruntime", which is the place where the simulated iOS OS is stored. I would imagine that on a real iOS device, it would be located at the path after "RuntimeRoot":

/System/Library/PrivateFrameworks/SFSymbols.framework/CoreGlyphs.bundle/Assets.car

Peeking into this Assets.car file, we can see that it has entries like this:

  {
    "AssetType" : "Image",
    "BitsPerComponent" : 8,
    "ColorModel" : "Monochrome",
    "Colorspace" : "gray gamma 22",
    "Compression" : "deepmap2",
    "DeploymentTarget" : "2019",
    "Encoding" : "Gray",
    "Glyph Size" : "Medium",
    "Glyph Weight" : "Regular",
    "Idiom" : "universal",
    "Name" : "square.lefthalf.filled",
    "NameIdentifier" : 54903,
    "Opaque" : false,
    "PixelHeight" : 27,
    "PixelWidth" : 27,
    "RenditionName" : "square.lefthalf.filled.svg",
    "Scale" : 2,
    "SHA1Digest" : "2299C5EE9722FDB79BC6BA4458980605076D4356BA01FC2107228DC99D53E42A",
    "SizeOnDisk" : 338,
    "State" : "Normal"
  },

Notice the "Name" properties are all SF symbol names.