Enhance Quick-Start Documentation and NDK compatiblity ?

[gajanak]

Hi,
at first thanks for this usefull template.

Perhaps this hels someone using this as base.

Documentation Quick-Start:
Installting android sdk,ndk,platforms using dpkg/apt sample:
apt install google-android-ndk-r25-installer install google-android-platform-30-installer google-android-build-tools-33.0.0-installer

for jarsigner:
apt install openjdk-19-jdk-headless

Using Build Tools > 22

The sysroot moved to /toolchains/llvm/prebuilt//sysroot starting with NDK r19. r22 removed the deprecated sysroot and platforms directories from the top-level of the NDK.

So this dirty hack to Sdk.zig are working (not perfect but perhaps a Hint for anyone with more experience):

diff --git a/Sdk.zig b/Sdk.zig
index 58e3b50..a6eb83a 100644
--- a/Sdk.zig
+++ b/Sdk.zig
@@ -81,9 +81,9 @@ pub fn init(b: *Builder, user_config: ?UserConfig, versions: ToolchainVersions)
 }

 pub const ToolchainVersions = struct {
-    android_sdk_version: u16 = 28,
-    build_tools_version: []const u8 = "28.0.3",
-    ndk_version: []const u8 = "21.1.6352462",
+    android_sdk_version: u16 = 30,
+    build_tools_version: []const u8 = "33.0.0",
+    ndk_version: []const u8 = "25.0.8775105",

     pub fn androidSdkString(self: ToolchainVersions, buf: *[5]u8) []u8 {
         return std.fmt.bufPrint(buf, "{d}", .{self.android_sdk_version}) catch unreachable;
@@ -561,7 +561,7 @@ pub fn compileAppLibrary(

     exe.defineCMacro("ANDROID", null);

-    const include_dir = std.fs.path.resolve(sdk.b.allocator, &[_][]const u8{ ndk_root, "sysroot/usr/include" }) catch unreachable;
+    const include_dir = std.fs.path.resolve(sdk.b.allocator, &[_][]const u8{ ndk_root, "toolchains/llvm/prebuilt/linux-x86_64/sysroot/usr/include" }) catch unreachable;
     exe.addIncludeDir(include_dir);

     exe.linkLibC();
@@ -572,66 +572,49 @@ pub fn compileAppLibrary(
     exe.setBuildMode(mode);

     const TargetConfig = struct {
-        lib_dir: []const u8,
         include_dir: []const u8,
-        libgcc_dir: []const u8,
         out_dir: []const u8,
         target: std.zig.CrossTarget,
     };

     const config: TargetConfig = switch (target) {
         .aarch64 => TargetConfig{
-            .lib_dir = "arch-arm64/usr/lib",
-            .libgcc_dir = "aarch64-linux-android-4.9",
             .include_dir = "aarch64-linux-android",
             .out_dir = "arm64-v8a",
             .target = zig_targets.aarch64,
         },
         .arm => TargetConfig{
-            .lib_dir = "arch-arm/usr/lib",
-            .libgcc_dir = "arm-linux-androideabi-4.9",
             .include_dir = "arm-linux-androideabi",
             .out_dir = "armeabi",
             .target = zig_targets.arm,
         },
         .x86 => TargetConfig{
-            .lib_dir = "arch-x86/usr/lib",
-            .libgcc_dir = "x86-4.9",
             .include_dir = "i686-linux-android",
             .out_dir = "x86",
             .target = zig_targets.x86,
         },
         .x86_64 => TargetConfig{
-            .lib_dir = "arch-x86_64/usr/lib64",
-            .libgcc_dir = "x86_64-4.9",
             .include_dir = "x86_64-linux-android",
             .out_dir = "x86_64",
             .target = zig_targets.x86_64,
         },
     };

-    const lib_dir_root = sdk.b.fmt("{s}/platforms/android-{d}", .{
+    const lib_dir = sdk.b.fmt("{s}/toolchains/llvm/prebuilt/linux-x86_64/sysroot/usr/lib/{s}-linux-android/{}/",.{
         ndk_root,
+        @tagName(target),
         sdk.versions.android_sdk_version,
     });

-    const lib_dir = std.fs.path.resolve(sdk.b.allocator, &[_][]const u8{ lib_dir_root, config.lib_dir }) catch unreachable;
-
-    const prebuilt_dir = switch (builtin.os.tag) {
-        .windows => "windows",
-        .linux => "linux",
-        .macos => "darwin",
-        else => unreachable,
-    };
-
-    const libgcc_path = sdk.b.fmt(
-        "{s}/toolchains/{s}/prebuilt/{s}-x86_64/lib/gcc/{s}/4.9.x/libgcc.a",
-        .{ ndk_root, config.libgcc_dir, prebuilt_dir, config.include_dir },
-    );
+    //const prebuilt_dir = switch (builtin.os.tag) {
+    //    .windows => "windows",
+    //    .linux => "linux",
+    //    .macos => "darwin",
+    //    else => unreachable,
+    //};

     exe.setTarget(config.target);
     exe.addLibPath(lib_dir);
-    exe.addObjectFile(libgcc_path);
     exe.addIncludeDir(std.fs.path.resolve(sdk.b.allocator, &[_][]const u8{ include_dir, config.include_dir }) catch unreachable);

     exe.setLibCFile(sdk.createLibCFile(config.out_dir, include_dir, include_dir, lib_dir) catch unreachable);
diff --git a/build/auto-detect.zig b/build/auto-detect.zig
index 98bafce..2bfd5bc 100644
--- a/build/auto-detect.zig
+++ b/build/auto-detect.zig
@@ -458,6 +458,10 @@ fn findProblemWithAndroidNdk(b: *Builder, versions: Sdk.ToolchainVersions, path:

     const ndk_include_path = std.fs.path.join(b.allocator, &[_][]const u8{
         path,
+"toolchains",
+"llvm",
+"prebuilt",
+"linux-x86_64", //<host-tag>
         "sysroot",
         "usr",
         "include",