decent-sampler: added icon and desktop file

pkgs/by-name/de/decent-sampler/package.nix

@@ -1,6 +1,9 @@
 { lib
 , stdenv
 , fetchzip
+, fetchurl
+, makeDesktopItem
+, copyDesktopItems
 , buildFHSEnv
 , alsa-lib
 , freetype
@@ -12,21 +15,41 @@ let
   pname = "decent-sampler";
   version = "1.10.0";
 
-  decent-sampler = stdenv.mkDerivation rec {
+  icon = fetchurl {
+    url = "https://archive.org/download/ds-256/DS256.png";
+    hash = "sha256-SV8zY5QJ6uRSrLuGTmT1zwGoIIXCV9GD2ZNiqK+i1Bc=";
+  };
+
+  decent-sampler = stdenv.mkDerivation {
     inherit pname version;
 
     src = fetchzip {
-      # dropbox link: https://www.dropbox.com/sh/dwyry6xpy5uut07/AABBJ84bjTTSQWzXGG5TOQpfa\
+      # dropbox links: https://www.dropbox.com/sh/dwyry6xpy5uut07/AABBJ84bjTTSQWzXGG5TOQpfa\
       url = "https://archive.org/download/decent-sampler-linux-static-download-mirror/Decent_Sampler-${version}-Linux-Static-x86_64.tar.gz";
       hash = "sha256-KYCf/F2/ziuXDHim4FPZQBARiSywvQDJBzKbHua+3SM=";
     };
 
+    nativeBuildInputs = [ copyDesktopItems ];
+
+    desktopItems = [
+      (makeDesktopItem {
+        type = "Application";
+        name = "decent-sampler";
+        desktopName = "Decent Sampler";
+        comment = "DecentSampler player";
+        icon = "decent-sampler";
+        exec = "decent-sampler";
+        categories = [ "Audio" "AudioVideo" ];
+      })
+    ];
+
     installPhase = ''
       runHook preInstall
 
       install -Dm755 DecentSampler $out/bin/decent-sampler
       install -Dm755 DecentSampler.so -t $out/lib/vst
       install -d "$out/lib/vst3" && cp -r "DecentSampler.vst3" $out/lib/vst3
+      install -Dm444 ${icon} $out/share/pixmaps/decent-sampler.png
 
       runHook postInstall
     '';
@@ -48,7 +71,8 @@ buildFHSEnv {
   runScript = "decent-sampler";
 
   extraInstallCommands = ''
-    cp -r ${decent-sampler.outPath}/lib $out/lib
+    cp -r ${decent-sampler}/lib $out/lib
+    cp -r ${decent-sampler}/share $out/share
   '';
 
   meta = with lib; {