Specify the path to the Java SDK used for the Android gradle build

[m4gr3d]

Introduce an editor setting to allow users the ability to specify the path to the Java SDK used for the Android gradle build.
At build time, a gradle task validates the java version and prints out an error if it doesn't match the target version

[akien-mga]

Looks great!

[YuriSizov]

Thanks!

[goatchurchprime]

I think there's still an issue here, because the values stored in the editor settings will continue to over-ride these JAVA_HOME and ANDROID_HOME environment values if they are not reset-to-default. This is only going to help people when they make a fresh install with no preset editor settings.

The most user-friendly option might be to make these boxes read-only in the UI with a tooltip that says they've been defined by the environment variables.

Attached is my nix-flake that I use to make godot with some edits to the source code that force-set all these values with the following substitutions:
flake.zip

                substituteInPlace platform/android/export/export_plugin.cpp \
                    --replace 'String sdk_path = EDITOR_GET("export/android/android_sdk_path")' 'String sdk_path = std::getenv("tunnelvr_ANDROID_SDK")'

                substituteInPlace platform/android/export/export_plugin.cpp \
                    --replace 'EDITOR_GET("export/android/debug_keystore")' 'std::getenv("tunnelvr_DEBUG_KEY")'

                substituteInPlace platform/android/export/export_plugin.cpp \
                    --replace 'EDITOR_GET("export/android/java_sdk_path")' 'std::getenv("tunnelvr_JAVA_SDK_PATH")'

                substituteInPlace editor/editor_paths.cpp \
                    --replace 'return get_data_dir().path_join(export_templates_folder)' 'return std::getenv("tunnelvr_EXPORT_TEMPLATES")'
                    
                    <snip>
                    
                        wrapProgram $out/bin/godot4 \
                            --set ANDROID_HOME "${androidenv}/share/android-sdk"\
                            --set JAVA_HOME "${pkgs.jdk17}/lib/openjdk"\
                            --set tunnelvr_ANDROID_SDK "${androidenv}/share/android-sdk"\
                            --set tunnelvr_JAVA_SDK_PATH "${pkgs.jdk17}/lib/openjdk"\
                            --set tunnelvr_EXPORT_TEMPLATES "${export-templates}/templates" \
                            --set tunnelvr_DEBUG_KEY "${debugKey}" \
                            --set GODOT_BLENDER3_PATH "${pkgs.blender}/bin/" \
                            --set GRADLE_OPTS "-Dorg.gradle.project.android.aapt2FromMavenOverride=${androidenv}/share/android-sdk/build-tools/34.0.0/aapt2"

[m4gr3d]

I'm not sure I understand the issue.. Those values are meant to override the env variables so that users with multiple Java and/or Android sdks can specify which one the Godot editor should use.

Making them read only defeats that purpose.

[akien-mga]

Cherry-picked for 4.2.2.