A library with bunch of handy methods. Static context only, no permissions required, works on API 8+.
public static Application getApplication() {}
public static Activity getCurrentActivity() {}
public static Handler getHandler() {}
public static void runOnUIThread(Runnable r) {}
public static Bitmap takeScreenshot() {}
public static void setActivityLifecycleListener(ActivityLifecycleListener listener) {}
How?
It's mostly reflection and knowledge about Android API internals.
Is it safe? I'm afraid of reflection
Of course it's not safe! Reflection is not checked at compilation time. It means that if anything changes in a future release of Android, this library will stop working.
Why don't you use ordinary core for these things?
I wrote tons of ordinary code already. I like doing fun stuff and I'm a pretty lazy coder. The outcome is here.