android - How to declare an object at class level and get intent data? -

i'm trying recive arraylist 1 activity , add data list , pass along again. thing is, when have declare @ class level question is. how data intent when declaring @ class level?

@override     protected void oncreate(bundle savedinstancestate) {         log.d(tag, "start oncreate listan");         super.oncreate(savedinstancestate);         setcontentview(r.layout.activity_listan);         bundle listan = getintent().getextras();         arraylist<produkt> lista = (arraylist<produkt>) getintent().getserializableextra("list");         if (lista.isempty()) {             log.d(tag, "lista==null");             listproduktadapter adapter = new listproduktadapter(listan.this, lista);             listview listview = (listview) findviewbyid(r.id.listview);             bundle produktinfo = getintent().getextras();             string name = produktinfo.getstring("name").tostring();             string allergen = produktinfo.getstring("allergen").tostring();             produkt produkt = new produkt(allergen, name);             log.d(tag, "gjort produkt");             lista.add(produkt);             listview.setadapter(adapter);         }         else {             listproduktadapter adapter = new listproduktadapter(listan.this, lista);             listview listview = (listview) findviewbyid(r.id.listview);             bundle produktinfo = getintent().getextras();             string name = produktinfo.getstring("name").tostring();             string allergen = produktinfo.getstring("allergen").tostring();             produkt produkt = new produkt(allergen, name);             log.d(tag, "gjort produkt");             lista.add(produkt);             listview.setadapter(adapter);         }     } 

here method pass along again.

@override protected void onactivityresult(int requestcode, int resultcode, intent data) {     intentresult result = intentintegrator.parseactivityresult(requestcode, resultcode, data);     if(result != null) {         if(result.getcontents() == null) {             log.d(tag, "scanning failed");             toast.maketext(this, "cancelled", toast.length_long).show();         } else {             log.d(tag, "scannad");             toast.maketext(this, "scanned: " + result.getcontents(), toast.length_long).show();             intent = new intent(this, getxml.class);             i.putextra("barcode", result.getcontents());             i.putextra("list", lista);             startactivity(i);             log.d(tag, "going new activity");         }     } else {         super.onactivityresult(requestcode, resultcode, data);     } } 

the error "can't resolve symbol 'lista'" on i.putextra("list", lista); on "onactivityresult"

solved:

i solved problem initiating object in mainactivity , passing through flow of activities empty until started adding data it.

you can use java interfaces this. if want use approach less complexity can use following method.

instead declaring 2 separate activity files, can declare activity file inside activity class file. such as

public class outerclass{     //instance method of outer class     void my_method(){       int num = 23;        //method-local inner class       class methodinner_demo{          public void print(){             system.out.println("this method inner class "+num);               }          }//end of inner class        //accessing inner class       methodinner_demo inner = new methodinner_demo();       inner.print();    }     public static void main(string args[]){       outerclass outer = new outerclass();       outer.my_method();               } } 

just can declare 2 activities in single file , can pass data 1 ease.

and declaring in manifest use following approach:

<activity android:name="com.example.foo.outeractivity$inneractivity" ></activity> 

but have decalre innerclass static using

public static class inneractivity{  }