remove standalone example, simplify readme

Makefile

@@ -91,15 +91,6 @@ release: update build-luajit
 	@echo "Application $(APPNAME) was built, type: release (unsigned), flavor: $(FLAVOR), version: $(NAME), release $(VERSION)"
 	@echo "WARNING: You'll need to sign this application to be able to install it"
 
-example: update clean build-luajit
-	@echo "Building HelloWorld example"
-	mkdir -p assets/module/
-	cp -pv examples/helloWorld/*.lua assets/module/
-	./gradlew -q -PversName=1.0 -PversCode=1 -PprojectName=HelloFromLua \
-		-PndkCustomPath=$(ANDROID_NDK_FULLPATH) app:$(BUILD_TASK)Debug
-	mkdir -p bin/
-	find app/build/outputs/apk/ -type f -name '*.apk' -exec mv -v {} bin/ \;
-
 lint:
 	./gradlew -PndkCustomPath=$(ANDROID_NDK_FULLPATH) $(LINT_TASK)Release
 

README.md

@@ -9,11 +9,7 @@ NativeActivity is available starting with platform android-9.
 
 Have a look at the Android NDK's "native-plasma" sample activity to get an idea what it does - or rather, is theoretically able to do. While the sample from NDK implements everything in C, in our case, we create a LuaJIT instance and hand off control to it instead. LuaJIT then handles the main loop. In this programming model, we have a thread which presents us with a "main" entry point and allow us to follow our own program flow as long as we poll for and react to events.
 
-A good number of Android native API headers are readily presented via FFI already. I'll probably add more along the way.
-
-For now - and probably ever, since Mike Pall recommends strongly to do so - the compilation of LuaJIT is not integrated into the Android build framework and has to be run separately.
-
-A wrapper script for building LuaJIT is provided. It **relies on NDK r15c**
+A good number of Android native API headers are readily presented via FFI already.
 
 Have a look at KOReader's [llapp_main.lua](https://github.com/koreader/koreader/blob/master/platform/android/llapp_main.lua) file. You can use it as a starting point for your own app.
 
@@ -22,30 +18,3 @@ The real starting point, called from JNI/C, is the run() function in android.lua
 ## Disclaimer
 
 This repo is used as glue code to run KOReader on Android.
-
-Usage on its own doesn't make much sense since you're expected to write your own drawing routines in Lua!
-A standalone example is attached (with no drawing routines!) in case you're curious what you'll get.
-
-
-## Building the example app
-
-### Export `ANDROID_NDK_HOME`
-
-```sh
-export ANDROID_NDK_HOME=/path/to/your/ndk/folder
-```
-
-### Build example APK for arm 32 bits
-
-```sh
-make example
-```
-
-
-### Build example APK for any other arch
-
-```sh
-ANDROID_ARCH=MY_ARCH make example
-```
-
-where `MY_ARCH` is either `x86`, `x86_64` or `arm64`