How to use Gallery View in Android, but on another page -


i've got 2 layout files in res/layout folder: main.xml , page2.xml. in main.xml i've got welcome info , button starts 

setcontentview(r.layout.page2);

to change page2.xml.

it worked fine till decided add gallery view in page2.xml.

when set begining contentview page2 below it's ok. 

public void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     setcontentview(r.layout.page2);      gallery g = (gallery) findviewbyid(r.id.gallery);            g.setadapter(new imageadapter(this));

but when call main.xml first show may start page... 

public void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     setcontentview(r.layout.main);      gallery g = (gallery) findviewbyid(r.id.gallery);            g.setadapter(new imageadapter(this));

the app returns error. know problem context in line

    g.setadapter(new imageadapter(this));

but don't know how pass right context or solve in way (but don't want have layout in 1 xml file).

it's not entirely clear explanation (logs never hurt), think you're getting null pointer exception because gallery not defined in main.xml. there 2 solutions problem:

  1. split 2 "pages" 2 activities. more natural way of dealing things. try rotating phone/emulator , you'll see mean. when user clicks on button or whatever, call startactivity() , call finish(), welcome activity not left hanging about.
  2. the problem findviewbyid() acts on whatever "visible" in activity right now. since did setcontentview(main), gallery not there. try "getting" gallery after make call "change pages" (setcontentview(r.layout.page2);).

however, advice go first option.


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