How to fire a event when the user enters the character in Android Edit Text? -

in android project. want fire event(display dialog) when user enters particular character (ex: when user enters "s") .i tried on text watcher dialog showing 2 times

please 1 me in

added code

mtext.addtextchangedlistener(new textwatcher() {          @override         public void ontextchanged(charsequence s, int start, int before,                 int count) {             // todo auto-generated method stub             if (s.charat(s.length() - 1) == 's') {                  dialog.show();             }         }          @override         public void beforetextchanged(charsequence s, int start, int count,                 int after) {             // todo auto-generated method stub          }          @override         public void aftertextchanged(editable s) {             // todo auto-generated method stub          }     }); 

you can add textwatcher, this:

 yourtextview.addtextchangedlistener(new textwatcher() {      @override      public void ontextchanged(charsequence s, int start, int before, int count) {      }       @override      public void beforetextchanged(charsequence s, int start, int count, int after) {      }       @override      public void aftertextchanged(editable editable) {       //handle text changed      }  });