android - How to use intent startactivityforresult method? -

i created library, , library has 4 activity. move between theese activitys intent, dont know how send result data, main application? start library this:

intent intent = new intent(this, libraryfirstactivity.class); startactivityforresult(intent, 1);  @override protected void onactivityresult(int requestcode, int resultcode, intent data) {     super.onactivityresult(requestcode, resultcode, data);     if (requestcode == 1){         if (resultcode == result_ok){             string result = data.getstringextra("result");             log.d("result", result);         }         if (resultcode == result_canceled){             toast.maketext(this, "canceled", toast.length_short).show();         }     } } 

i start libraryfirstactvity. in libraryfirstactivity go librarysecondactivity:

intent intent = new intent(this, librarysecondactivity.class); startactivity(intent); finish(); 

but can go librarythirdactivity too, or other. how can return main app onactivityresult() method?

1) firstactivity call secondactivity using startactivityforresult() method.

for example:

intent = new intent(this, secondactivity.class); startactivityforresult(i, 1); 

2) in secondactivity set data want return firstactivity. if don't want return back, don't set any.

for example: in secondactivity if want send data:

intent returnintent = new intent(); returnintent.putextra("result", result); setresult(result_ok,returnintent); finish(); 

the result can of type : string / boolean / int / long / bundle ...

if don't want return data:

intent returnintent = new intent(); setresult(result_canceled, returnintent); finish(); 

3) in firstactivity class write following code onactivityresult() method.

protected void onactivityresult(int requestcode, int resultcode, intent data) {     if (requestcode == 1) {         if(resultcode == result_ok){             string result=data.getstringextra("result");         }         if (resultcode == result_canceled) {             //write code if there's no result         }     } }//onactivityresult