How do i transfer a final string from one activity to another in android?

Question

I know about this and it works fine

    Intent i1 = new Intent(Login.this, Welcome.class);
    i1.putExtra("username","the name");
    startActivity(i1);

and this in the next layout:

    String username = getIntent().getStringExtra("username");

but i need to tranfer a final string, I tried this but it doesnt work:

    public static final String ADMIN_USERNAME= "user";

    Intent intent = new Intent(Login.this,SignUp.class);
    intent.putExtra("admin_username",ADMIN_USERNAME);
    startActivity(intent);

and this in the next layout:

    public final String ADMIN_USERNAME= getIntent().getStringExtra("admin_username");

im getting this error:

    Attempt to invoke virtual method 'java.lang.String android.content.Intent.getStringExtra(java.lang.String)' on a null object reference

Can you give more information? For example what error you are taking? Maybe full class for letting us to check your namespace scope? — Emre Aktürk, May 18 '17 at 17:19
For string constants like you have there, just make it static and access it directly in the other activity. — Daniel Nugent, May 18 '17 at 17:20

score 1 · Answer 1 · edited May 18 '17 at 18:12

1

When you declare a string constant as static like this:

public static final String ADMIN_USERNAME= "user";

you don't need to use intent extras to access to the value in another activity, just access the ADMIN_USERNAME string constant directly:

if (someString.equals(MyActivity.ADMIN_USERNAME)) {
    //Do something....
}

edited May 18 '17 at 18:12

Daniel Nugent

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answered May 18 '17 at 17:34

Carmen

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Emre Aktürk · Answer 2 · 2017-05-18T18:00:06.207

0

Your intent is null. İt's a early call in lifecycle

String username = getIntent().getStringExtra("admin_username");

Make sure you call this line in onCreate if you are calling inside onAttach

Also make sure your key is correct. Please notice I fixed it also as "admin_username"

Good luck

Emre

edited May 18 '17 at 18:00

answered May 18 '17 at 17:53

Emre Aktürk

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How do i transfer a final string from one activity to another in android?

2 Answers2