Android Learning activity jump and transfer value

Activity jumps and passes values. Mainly through the intent class. The role of intent is to activate the component and the accompanying data.

First, activity jumps

Method One
Intent Intent = new Intent (a.this, B.class);
StartActivity (Intent)

Method Two
Intent Intent = new Intent ();
Intent.setclass (A.this, B.class);
StartActivity (Intent);

Implementation from a jump to B (A, B are inherited from activity)

II. Transmission of data

Activity A transmits data

Method One
Intent Intent = new Intent ();
Intent.setclass (A.this, B.class);
Intent.putextra ("name", "XY");
Intent.putextra ("Age", 22);

StartActivity (Intent);

Method Two
Intent Intent = new Intent (a.this, B.class);
Bundle bundle = new bundle ();
Bundle.putstring ("name", "XY");
Bundle.putint ("Age", 22);

Intent.putextras (bundle);
StartActivity (Intent);

Activity B receives data

Get the number of references 1
Intent Intent = This.getintent ();
String name = Intent.getstringextra ("name");
int age = Intent.getintextra ("Age", 22); The default value is 22

Get the number of references 2
Bundle bundle = Intent.getextras ();
String name2 = bundle.getstring ("name");
int age2 = Bundle.getint ("Age", 22);

Both of these can be obtained, not with the corresponding method one by one.

Android Learning activity jump and transfer value