Android-activity use (2)-Pass value

First, simple transmission value

1, modify the Mainactivity

    protected voidonCreate (Bundle savedinstancestate) {super.oncreate (savedinstancestate);        Setcontentview (R.layout.activity_main); //cast to Button, must be placed after Setcontentviewbtnsatrtaty1=(Button) Findviewbyid (r.id.btnstartaty1); //set the event listener for the buttonBtnsatrtaty1.setonclicklistener (//an anonymous class that implements the Onclicklistener interface            NewView.onclicklistener () {@Override Public voidOnClick (view view) {//event to start the Aty1//parameter One: examples of mainactivity//parameter two: The class of the activity to be started is defined as type class//This refers to the inner class that implements the OnclicklistenerIntent i=NewIntent (mainactivity. This, Aty1.class); I.putextra ("txt","Hello Aty1");                StartActivity (i);        }        }); System. out. Print ("onCreate"); }

2, modify Aty1 accept data and display

tvout=(TextView) Findviewbyid (r.id.tvout); Tvout.settext (Getintent (). Getstringextra("txt "));

Second, the bundle transfer value is a bit more complex data

1, modify the mainactivity through the bundle transfer value

Intent i=New Intent (mainactivity.  this, Aty1. class ); Bundle Data=new  bundle ();d ata.putstring ("","Hello Aty1"  ); I.putextras (data); startactivity (i) ;

2, modify Aty1 accept data and display

tvout=(TextView) Findviewbyid (r.id.tvout); Bundle Data=getintent (). Getextras (); String txt=data.getstring ("txt"); tvout.settext (TXT);

Second, the transfer of activity back

You cannot use startactivity instead of Startactivityforresult

1. Modify Aty1 to set the return value when the page is closed

        btnclose=(Button) Findviewbyid (r.id.btnstartaty1);        Btnclose.setonclicklistener (new View.onclicklistener () {            @Override            void onClick (view view) {Intent i=new Intent (); I.putextra ("result","Hello mainactivity"); Setresult (0, i); Finish ();}});             

2. Modify Mainactivity to accept the callback value

    protected void onactivityresult (intint  resultcode, Intent data) {        String result= Data.getstringextra ("result");        Tvout.settext (result);        Super.onactivityresult (Requestcode, ResultCode, data);    }

Android-activity use (2)-Pass value