Apps About the addToBackStack() method

[ac4android]

In very simple terms, lets say I have several fragments and on the UI, the user can click on any item which then selects one of the fragments. The user must be able to use the "back" key to get back to previous screen.

I tend to end up with these few lines of codes:

FragmentTransaction ftx = getFragmentManager().beginTransaction();
ftx.replace(R.id.my_container_frame, fragment);
ftx.addToBackStack(null);

QUESTION: But doesn't the null in addToBackStack(null) mean it won't be added to the backstack?

 

[Deleted User]

The parameter is an optional name for the back stack state, or null if you don't want to call it anything. The fragment is added to the back stack, regardless of what parameter value you use.

http://stackoverflow.com/questions/...meaning-of-addtobackstack-with-null-parameter

 

[ac4android]

Read the answers in the link, the null still seems spurious.
Under what circumstances would I want a none-null label or tag ?
Do you have some practical examples?

 

[Deleted User]

Well a quick Google reveals...

http://www.codeproject.com/Questions/818401/What-is-the-purpose-of-null-in-addToBackStack-null

So basically, if you need to use the FragmentManager to retrieve the fragment later, you can do this using the name you supplied in the parameter.

If you don't need to do the above, use null.