android - Remove listener from ViewTreeObserver -



android - Remove listener from ViewTreeObserver -

i need hear exact 1 global layouting event set right scrolling positions. after searching little why calls scrollto(x,y) seem ignored discovered these can called in meaningful way 1 time whole layout known. registering globallayoutlistener , defer phone call scrollto().

the problem is, want scrolling once. figured phone call removeglobalonlayoutlistener() stop listening. resulted in exception: illegalstateexception: viewtreeobserver not alive, phone call getviewtreeobserver() again. thought fine, if observer not live won't fire events. unfortunately does: view scrolled every time layout somehow changes.

my current iteration of code looks this. alter create sure phone call scrolltogridpos() takes place once? know add together local field mhasfired inner class seems dirty hack me ...

final viewtreeobserver vto = mlayout.getviewtreeobserver(); vto.addongloballayoutlistener(new ongloballayoutlistener() { public void ongloballayout() { scrolltogridpos(getcenterpoint(), false); if (vto.isalive()) { vto.removeglobalonlayoutlistener(this); } } });

you should using mlayout.getviewtreeobserver() in ongloballayout(), rather trying access old one. eg.

mlayout.getviewtreeobserver().addongloballayoutlistener(new ongloballayoutlistener() { public void ongloballayout() { scrolltogridpos(getcenterpoint(), false); mlayout.getviewtreeobserver().removeglobalonlayoutlistener(this); } });

android

Comments

Post a Comment

Popular posts from this blog

Delphi change the assembly code of a running process -

Delphi change the assembly code of a running process - i'm trying alter address 00741fa5 has push test.009e721c . alter push test.009e71c8 . procedure callback; asm force $9e71c8 end; procedure tform2.btn1click(sender: tobject); var ppid :dword; pprocess : cardinal; begin getwindowthreadprocessid(findwindow(nil,pchar('test')), @ppid); pprocess := openprocess(process_all_access, false, ppid); injectasm(pprocess, $741fa5, 10, integer(@callback), 0); end; here injectasm function (with error checking) function injectasm(process: longword; injectaddress, injectsize, codeaddress, codesize : integer): pointer; var csize, rsize : integer; replaced : array of byte; jmp : array [0..4] of byte; jmpaddress : integer; nopv : byte; : integer; nbr: ulong_ptr; begin //injectsize must equal or greater 5, because need space our //(far) jmp wwxxyyzz instruction //if there's no space, inject in place of few instructions if injectsize ...
Read more

json - Hibernate and Jackson (java.lang.IllegalStateException: Cannot call sendError() after the response has been committed) -

json - Hibernate and Jackson (java.lang.IllegalStateException: Cannot call sendError() after the response has been committed) - hello have problem hibernate , jackson. have 2 pojos @entity @table(name = "users") public class user implements serializable { static final long serialversionuid = 4235637833262722256l; @id @generatedvalue private int id; @column(name = "creation_date") private date creationdate; @column(name = "first_name") private string firstname; @column(name = "last_name") private string lastname; @version @column(name = "version") private int version; @column(name = "e_mail") private string email; @column(name = "enabled") private boolean enabled; @column(name = "login") private string login; @column(name = "password") private string password; @jsonmanagedreference("role") @onetomany(mappedby = "user", cascade = cascadetype.all,fetch = fetchtyp...
Read more

C++ 11 "class" keyword -

C++ 11 "class" keyword - i've started using c++ 11 little bit more , have few questions on special uses of class keyword. know it's used declare class, there's 2 instances have seen don't understand: method<class t>(); and class class_name *var; why precede typename keyword class in first example, , keyword pointer in sec example? that known elaborated type specifier , necessary when class name "shadowed" or "hidden" , need explicit. class t { }; // love of god don't t t; t t2; if compiler smart, give these warnings: main.cpp:15:5: error: must utilize 'class' tag refer type 't' in scope t t2; ^ class main.cpp:14:7: note: class 't' hidden non-type declaration of 't' here t t; ^ if class not defined, deed forwards declaration. for example: template <typename t> void method() { using type = typename t::value_type; } method...
Read more