android - Validation on EditText in alertDialog -

i trying add empty field validations on edittext on alertdialog. after field empty error message not getting displayed, instead alertdialog closing. if conditions working i'm not able post operations if of field empty.

here java sample code:

public class touractivity extends appcompatactivity {  private layoutinflater inflater; private floatingactionbutton fab;  @override protected void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     setcontentview(r.layout.activity_tour);     toolbar toolbar = (toolbar) findviewbyid(r.id.toolbar);     setsupportactionbar(toolbar);     fab = (floatingactionbutton) findviewbyid(r.id.fab);      fab.setonclicklistener(new view.onclicklistener() {         @override         public void onclick(view view) {             inflater = touractivity.this.getlayoutinflater();             view content = inflater.inflate(r.layout.activity_add_new_trip, null);             final edittext editevent = (edittext) content.findviewbyid(r.id.edtxt_eventname);             final edittext editstartdate = (edittext) content.findviewbyid(r.id.edtxt_eventsdate);               alertdialog.builder builder = new alertdialog.builder(touractivity.this);             builder.setview(content)                     .settitle("add event")                     .setpositivebutton(android.r.string.ok,                             new dialoginterface.onclicklistener() {                                 @override                                 public void onclick(dialoginterface dialog, int which) {                                      editevent.seterror(null);                                     editstartdate.seterror(null);                                      boolean cancel = false;                                     view focusview = null;                                      if (textutils.isempty(editevent.gettext().tostring()))) {                                         editevent.seterror("please enter event name.");                                         return;                                     }                                      if (textutils.isempty(editstartdate.gettext().tostring())) {                                         editstartdate.seterror("please enter event start date.");                                         focusview = editstartdate;                                         cancel = true;                                     }                                       if (cancel == true) {                                         snackbar.make(findviewbyid(android.r.id.content),                                                 "event unsuccessful.", snackbar.length_long)                                                 .setactiontextcolor(color.red)                                                 .show();                                         focusview.requestfocus();                                     } else {                                         // action here                                     }                                 }                             })                     .setnegativebutton(cancel, new dialoginterface.onclicklistener() {                          @override                         public void onclick(dialoginterface dialog, int which) {                             dialog.dismiss();                         }                     });             alertdialog dialog = builder.create();             dialog.show();         }     }); } } 

try this

 if (textutils.isempty(edevent)) {                                     editevent.seterror("please enter event name.");                                     editevent.requestfocus();                                     return;                                 }