Android Intent Learning Notes

Activity switching

Two different ways

>1. Direct Jump

New Intent (mainactivity.  this, secondactivity. class ); startactivity (intent);

>> need to carry parameters is required to use

Intent.putextra ("Key", "value");

>> target activity take parameter use

Getintent (). Getstringextra ("key")

>2. Jump with return value

New Intent (mainactivity.  this, secondactivity. class ); Intent.putextra ("key"1);

>> target Activity returns

New Intent (); Intent.putextra ("code", "OK"), Setresult ((int)Requestcode, Intent);                Finish ();

>>>finish () function: Execution finishes destroying this activity, this activityresult returns to the caller and calls the Onactivityresult () function.

>> original activity accept the return value operation

    @Override    protectedvoid onactivityresult (intint  ResultCode, Intent data) {        super. Onactivityresult (Requestcode, ResultCode, data);        Determine the        operation if (requestcode==1 && resultcode==2)            {medittext.settext ( Data.getstringextra ("code"));             // Toast.maketext (Mainactivity.this, Data.getstringextra ("code"), Toast.length_long). Show ();         }    }

Android Intent Learning Notes