android - call back function java -

i have class called buycoins, within class have method addlisteneronspinneritemselection()

public void addlisteneronspinneritemselection() {     spinner1 = (spinner) findviewbyid(r.id.spinner1);     textview t=(textview) findviewbyid(r.id.conversion);     customonitemselectedlistener c = new customonitemselectedlistener(t);     spinner1.setonitemselectedlistener(c);     //string stockcode=c.getstock();     //log.d(tag,"message"); } 

this creates new object detects item(product) selected on spinner. pass buyclass. have attempted lines commented out, value receive null.

public class customonitemselectedlistener implements onitemselectedlistener {  ... public string stock;  ...  public void onitemselected(adapterview<?> parent, view view, int pos, long id) {      string selected=parent.getitematposition(pos).tostring();      switch(selected) {         case "20 coins":             toast.maketext(parent.getcontext(),             "onitemselectedlistener : " + selected,             toast.length_short).show();             t.settext("$20");             this.setstock("20coins");             break;    ...    }     private void setstock(string s) {        stock=s;    }     public string getstock() {        return stock;    }  } 

the problem you're querying listener right after adding it, i.e. event can't possibly have happend yet. since don't know when happening (if @ all) you'll need decouple that.

example (simple pseudo code, started):

class model {   string stock; }  class listener {   model model;    listener( model m) {     model = m;   }    //in case component might spinner or parent, depending on rest of code   void onitemselected( component c ) {     m.stock = c.gettext();   } } 

and when create , register listener:

class buycoins {   model model;  //initialize     ...    void initlisteners() {     spinner.addlistener( new listener(model) );   } }