Per-program Flet client app IDs so the dock shows the right icons

Main.py

@@ -1,6 +1,7 @@
 """SaraSuite entry point: installs, updates and removes Sara programs.
 With arguments it runs the command-line mode instead (see Cli.py)."""
 
+import importlib.util
 import os
 import shutil
 import sys
@@ -11,7 +12,7 @@ import flet as ft
 
 from Core import (
     AppName, ApplyAppearance, AssetsDir, BuildTheme, BundledFontFamily, ChipButtonStyle, DataDir,
-    DataHome, EffectiveSettings, LoadConfig, Palette,
+    DataHome, EffectiveSettings, LoadConfig, ManifestsDir, Palette,
 )
 from Dialogs import ShowInstallDialog, ShowOptionsDialog, ShowRemoveDialog, ShowUpdateDialog
 from Installer import Apply, Fetch, FetchCommit, GetStatus, PlanConfigs, PlanRemoval, Remove, SourceVersion
@@ -27,6 +28,15 @@ _MenuEntry = DataHome / "applications" / "SaraSuite.desktop"
 _MenuIcon = DataDir / "SaraSuite.png"
 
 
+def _LoadFletIdentity():
+    # Lives in Programs/ (bundled as data) because installed programs get a
+    # copy of the same file next to them.
+    Spec = importlib.util.spec_from_file_location("FletIdentity", ManifestsDir / "FletIdentity.py")
+    Module = importlib.util.module_from_spec(Spec)
+    Spec.loader.exec_module(Module)
+    return Module
+
+
 def _SetMenuEntry(Enabled: bool) -> None:
     if not Enabled:
         _MenuEntry.unlink(missing_ok=True)
@@ -39,7 +49,7 @@ def _SetMenuEntry(Enabled: bool) -> None:
         "[Desktop Entry]\nType=Application\nName=SaraSuite\n"
         "Comment=Install, update and remove Sara programs\n"
         f"Exec={_AppImage}\nIcon={_MenuIcon}\nTerminal=false\n"
-        f"Categories=System;\nStartupNotify=true\nStartupWMClass={AppName}\n"
+        f"Categories=System;\nStartupNotify=true\nStartupWMClass=srhtnin.{AppName}\n"
     )
 
 
@@ -234,7 +244,8 @@ if __name__ == "__main__":
         from Cli import Run
 
         sys.exit(Run(sys.argv[1:]))
-    # The window's app ID, so the desktop matches it to SaraSuite.desktop
-    # (icon, name) instead of showing it as Flet's generic "com.appveyor.flet".
-    os.environ.setdefault("FLET_APP_ID", AppName)
+    # A Flet client copy with the window app ID srhtnin.SaraSuite, so the
+    # desktop matches the window to SaraSuite.desktop (StartupWMClass) instead
+    # of showing it as "com.appveyor.flet". See Programs/FletIdentity.py.
+    os.environ.setdefault("FLET_VIEW_PATH", _LoadFletIdentity().ClientFor(f"srhtnin.{AppName}"))
     ft.run(Main, assets_dir=str(AssetsDir))

Packaging/BuildAppImage.sh

@@ -30,7 +30,7 @@ Exec=SaraSuite
 Icon=SaraSuite
 Terminal=false
 Categories=System;
-StartupWMClass=SaraSuite
+StartupWMClass=srhtnin.SaraSuite
 DESKTOP
 
 mkdir -p dist

Programs/FletIdentity.py

@@ -0,0 +1,67 @@
+"""Give a Flet program's window its own app ID on Linux, so the desktop can
+match it to the program's .desktop entry (icon, name) instead of showing
+every Flet program as "com.appveyor.flet" with a generic icon.
+
+The Flet client's ID is a string built into its small launcher binary
+(`flet`, ~24 KB); the client sets it as both its GTK application ID and its
+process name, so Flet's own FLET_APP_ID (which only changes argv[0]) can't
+override it, on Wayland or X11. Instead this makes a per-program copy of the
+client in ~/.cache/SaraSuite/FletClient/ with that string replaced; the big
+parts (lib/, data/, share/) are symlinks to the original, so a copy costs
+~24 KB. Pointing FLET_VIEW_PATH at it makes Flet use the copy.
+
+Used two ways:
+- SaraSuite imports it and calls ClientFor() before ft.run.
+- Installed programs' launchers run it with their own venv's python:
+      export FLET_VIEW_PATH="$(python FletIdentity.py srhtnin.SaraFem)"
+  It prints the copy's folder, or nothing if anything goes wrong, in which
+  case Flet just uses its normal client.
+"""
+
+import sys
+from pathlib import Path
+
+OriginalId = b"com.appveyor.flet"
+CopiesDir = Path.home() / ".cache" / "SaraSuite" / "FletClient"
+
+
+def ClientFor(AppId: str) -> str:
+    """Folder of a client copy whose app ID is AppId ("" if not possible).
+    AppId needs a dot (a GTK rule) and at most 17 characters, the length of
+    the original it replaces in place."""
+    try:
+        Encoded = AppId.encode("ascii")
+        if "." not in AppId or not 0 < len(Encoded) <= len(OriginalId):
+            return ""
+        from flet_desktop import ensure_client_cached  # the program's own Flet version
+
+        Original = Path(ensure_client_cached()) / "flet"
+        Binary = (Original / "flet").read_bytes()
+        Copy = CopiesDir / f"{Original.parent.name}-{AppId}" / "flet"
+        Patched = Binary.replace(
+            b"\x00" + OriginalId + b"\x00",
+            b"\x00" + Encoded.ljust(len(OriginalId), b"\x00") + b"\x00",
+        )
+        if Binary.count(b"\x00" + OriginalId + b"\x00") != 1:
+            return ""  # not the client layout this was written for
+
+        Target = Copy / "flet"
+        if not (Target.exists() and Target.read_bytes() == Patched):
+            Copy.mkdir(parents=True, exist_ok=True)
+            for Part in ("lib", "data", "share"):
+                Link = Copy / Part
+                if Link.is_symlink() or Link.exists():
+                    Link.unlink()
+                if (Original / Part).exists():
+                    Link.symlink_to(Original / Part)
+            Temporary = Target.with_suffix(".new")
+            Temporary.write_bytes(Patched)
+            Temporary.chmod(0o755)
+            Temporary.replace(Target)
+        return str(Copy)
+    except Exception:
+        return ""
+
+
+if __name__ == "__main__":
+    print(ClientFor(sys.argv[1]) if len(sys.argv) > 1 else "")

Programs/SaraFem/Manifest.toml

@@ -65,3 +65,8 @@ Note = "thumbnail cache"
 Path = "{ConfigHome}/SaraFem"
 Kind = "Config"
 Note = "old pre-SaraSuite config location"
+
+# Shared with the other Flet programs; see Programs/FletIdentity.py.
+[[Templates]]
+Source = "../../FletIdentity.py"
+Target = "{ProgramDir}/FletIdentity.py"

Programs/SaraFem/Templates/Launch.sh

@@ -1,7 +1,8 @@
 #!/bin/sh
 # Written by SaraSuite. Runs from the app folder so Flet finds assets/.
-# The window's app ID, so the desktop matches it to {Name}.desktop (icon, name)
-# instead of showing every Flet program as "com.appveyor.flet".
-export FLET_APP_ID="{Name}"
+# A Flet client copy with the window app ID srhtnin.{Name}, so the desktop
+# matches the window to {Name}.desktop (StartupWMClass) instead of showing it
+# as "com.appveyor.flet". Empty if that fails: Flet then uses its own client.
+export FLET_VIEW_PATH="$("{Python}" "{ProgramDir}/FletIdentity.py" "srhtnin.{Name}")"
 cd "{AppDir}" || exit 1
 exec "{Python}" Main.py "$@"

Programs/SaraFem/Templates/SaraFem.desktop

@@ -8,4 +8,4 @@ Terminal=false
 Categories=System;FileManager;
 MimeType=inode/directory;
 StartupNotify=true
-StartupWMClass={Name}
+StartupWMClass=srhtnin.{Name}

Programs/SaraSort/Manifest.toml

@@ -25,3 +25,8 @@ Target = "{ApplicationsDir}/SaraSort.desktop"
 Path = "{ConfigDir}"
 Kind = "Config"
 Note = "SaraSort's settings, flowchart layout and your templates"
+
+# Shared with the other Flet programs; see Programs/FletIdentity.py.
+[[Templates]]
+Source = "../../FletIdentity.py"
+Target = "{ProgramDir}/FletIdentity.py"

Programs/SaraSort/Templates/Launch.sh

@@ -1,7 +1,8 @@
 #!/bin/sh
 # Written by SaraSuite. Runs from the app folder so Flet finds assets/.
-# The window's app ID, so the desktop matches it to {Name}.desktop (icon, name)
-# instead of showing every Flet program as "com.appveyor.flet".
-export FLET_APP_ID="{Name}"
+# A Flet client copy with the window app ID srhtnin.{Name}, so the desktop
+# matches the window to {Name}.desktop (StartupWMClass) instead of showing it
+# as "com.appveyor.flet". Empty if that fails: Flet then uses its own client.
+export FLET_VIEW_PATH="$("{Python}" "{ProgramDir}/FletIdentity.py" "srhtnin.{Name}")"
 cd "{AppDir}" || exit 1
 exec "{Python}" Main.py "$@"

Programs/SaraSort/Templates/SaraSort.desktop

@@ -7,4 +7,4 @@ Icon={AppDir}/assets/Icon.png
 Terminal=false
 Categories=Utility;
 StartupNotify=true
-StartupWMClass={Name}
+StartupWMClass=srhtnin.{Name}

Programs/SaraTag/Manifest.toml

@@ -35,3 +35,8 @@ Target = "{ApplicationsDir}/SaraTag.desktop"
 Path = "{ConfigDir}"
 Kind = "Config"
 Note = "SaraTag's settings, Records, Libraries, history and Lexicons (Books next to your files are never touched)"
+
+# Shared with the other Flet programs; see Programs/FletIdentity.py.
+[[Templates]]
+Source = "../../FletIdentity.py"
+Target = "{ProgramDir}/FletIdentity.py"

Programs/SaraTag/Templates/Launch.sh

@@ -1,7 +1,8 @@
 #!/bin/sh
 # Written by SaraSuite. Runs from the app folder so Flet finds assets/.
-# The window's app ID, so the desktop matches it to {Name}.desktop (icon, name)
-# instead of showing every Flet program as "com.appveyor.flet".
-export FLET_APP_ID="{Name}"
+# A Flet client copy with the window app ID srhtnin.{Name}, so the desktop
+# matches the window to {Name}.desktop (StartupWMClass) instead of showing it
+# as "com.appveyor.flet". Empty if that fails: Flet then uses its own client.
+export FLET_VIEW_PATH="$("{Python}" "{ProgramDir}/FletIdentity.py" "srhtnin.{Name}")"
 cd "{AppDir}" || exit 1
 exec "{Python}" Main.py "$@"

Programs/SaraTag/Templates/SaraTag.desktop

@@ -7,4 +7,4 @@ Icon={AppDir}/assets/Icon.png
 Terminal=false
 Categories=Utility;Graphics;
 StartupNotify=true
-StartupWMClass={Name}
+StartupWMClass=srhtnin.{Name}