android - execute other app method from reflection -

android - execute other app method from reflection -

i have 1 app a, , installed device.

public class a1 extends activity { void oncreate() ... void onresume() ... void showtoast() { toast.maketext(this, "showa1", toast.length_short).show(); } }

and wrote app b, want execute a1.showtoast(), encounter nullpointerexception @ a1.showtoast().

@suppresswarnings("unchecked") @override public void onclick(view v) { string packagepath = "a"; string classpath = "a.a1"; seek { string apkname = getpackagemanager().getapplicationinfo( packagepath, 0).sourcedir; pathclassloader pathclassloader = new pathclassloader(apkname, classloader.getsystemclassloader()); class<activity> handler = (class<activity>) class.forname( classpath, true, pathclassloader); method[] mm = handler.getdeclaredmethods(); (method m : mm) { log.d("method", m.getname()); } method method = handler.getdeclaredmethod("showtoast", (class[]) null); method.setaccessible(true); method.invoke(handler.newinstance(), (object[]) null); } grab (exception e) { e.printstacktrace(); } }

i know a1 not initialize, "this" null. can help me problem?

android