define ndk in gradle props

.github/workflows/build.yml

@@ -13,7 +13,6 @@ jobs:
       KEY_PATH: ${{ github.workspace }}/apps/weblibre/key.jks
       KEY_PASSWORD: ${{ secrets.KEY_PASSWORD }}
       KEY_ALIAS: ${{ secrets.KEY_ALIAS }}
-      ANDROID_NDK_VERSION: 28.2.13676358
     permissions:
       contents: write
     steps:
@@ -41,6 +40,14 @@ jobs:
       - name: Install Android NDK
         run: |
           set -euo pipefail
+          ANDROID_NDK_VERSION="$(
+            sed -n 's/^weblibre\.ndkVersion[[:space:]]*=[[:space:]]*//p' \
+              apps/weblibre/android/gradle.properties
+          )"
+          if [[ -z "$ANDROID_NDK_VERSION" ]]; then
+            echo "Missing weblibre.ndkVersion in apps/weblibre/android/gradle.properties" >&2
+            exit 1
+          fi
           set +e
           yes | "$ANDROID_HOME/cmdline-tools/latest/bin/sdkmanager" --install "ndk;$ANDROID_NDK_VERSION"
           sdkmanager_status=${PIPESTATUS[1]}
@@ -50,6 +57,7 @@ jobs:
           fi
           test -f "$ANDROID_HOME/ndk/$ANDROID_NDK_VERSION/source.properties"
           {
+            echo "ANDROID_NDK_VERSION=$ANDROID_NDK_VERSION"
             echo "ANDROID_NDK_HOME=$ANDROID_HOME/ndk/$ANDROID_NDK_VERSION"
             echo "ANDROID_NDK_ROOT=$ANDROID_HOME/ndk/$ANDROID_NDK_VERSION"
             echo "NDK_HOME=$ANDROID_HOME/ndk/$ANDROID_NDK_VERSION"

apps/weblibre/android/build.gradle

@@ -2,7 +2,7 @@
 ext {
     compileSdkVersion   = 36
     targetSdkVersion    = 36
-    ndkVersion          = "28.2.13676358"
+    ndkVersion          = providers.gradleProperty("weblibre.ndkVersion").get()
 }
 
 buildscript {

apps/weblibre/android/gradle.properties

@@ -1,4 +1,5 @@
 org.gradle.jvmargs=-Xmx4G -XX:+HeapDumpOnOutOfMemoryError
+weblibre.ndkVersion=28.2.13676358
 android.useAndroidX=true
 android.enableJetifier=true
 # This builtInKotlin flag was added automatically by Flutter migrator

native/go_mobile_runtime/README.md

@@ -39,6 +39,7 @@ The output AAR is written to `native/go_mobile_runtime/build/weblibre-go.aar`.
 
 GitHub release builds clone the pinned sources from `pins.env` and run the same
 Melos command before building the Flutter APK/AAB artifacts. The app Gradle
-build and CI native runtime build both use Android NDK r28c (`28.2.13676358`),
-matching Flutter 3.44's default NDK. This is new enough for the `cronet-go`
-Android arm64 archives linked by sing-box's naive outbound path.
+build and CI native runtime build both read `weblibre.ndkVersion` from
+`apps/weblibre/android/gradle.properties`; it is currently Android NDK r28c
+(`28.2.13676358`), matching Flutter 3.44's default NDK. This is new enough for
+the `cronet-go` Android arm64 archives linked by sing-box's naive outbound path.

native/go_mobile_runtime/scripts/build-android.sh

@@ -9,6 +9,11 @@ REPO_ROOT="$(cd "$RUNTIME_DIR/../.." && pwd -P)"
 # shellcheck source=../pins.env
 source "$RUNTIME_DIR/pins.env"
 
+GRADLE_PROPERTIES="$REPO_ROOT/apps/weblibre/android/gradle.properties"
+DEFAULT_ANDROID_NDK_VERSION="$(
+  sed -n 's/^weblibre\.ndkVersion[[:space:]]*=[[:space:]]*//p' "$GRADLE_PROPERTIES"
+)"
+
 DEFAULT_SING_BOX_SOURCE="$(cd "$REPO_ROOT/.." && pwd -P)/sing-box"
 DEFAULT_IPTPROXY_SOURCE="$(cd "$REPO_ROOT/.." && pwd -P)/IPtProxy"
 
@@ -18,7 +23,7 @@ DNSTT_SOURCE="${DNSTT_SOURCE:-$IPTPROXY_SOURCE/dnstt}"
 OUTPUT_AAR="${OUTPUT_AAR:-$RUNTIME_DIR/build/weblibre-go.aar}"
 TARGET="${TARGET:-android}"
 ANDROID_API="${ANDROID_API:-24}"
-ANDROID_NDK_VERSION="${ANDROID_NDK_VERSION:-28.2.13676358}"
+ANDROID_NDK_VERSION="${ANDROID_NDK_VERSION:-$DEFAULT_ANDROID_NDK_VERSION}"
 INSTALL_GOMOBILE=1
 ALLOW_DIRTY=0
 DEBUG=0
@@ -193,6 +198,11 @@ if ! command -v go >/dev/null 2>&1; then
   exit 1
 fi
 
+if [[ -z "$ANDROID_NDK_VERSION" ]]; then
+  echo "Missing weblibre.ndkVersion in $GRADLE_PROPERTIES." >&2
+  exit 1
+fi
+
 if [[ -z "${ANDROID_HOME:-}" && -d "$HOME/Android/Sdk" ]]; then
   export ANDROID_HOME="$HOME/Android/Sdk"
 fi