Android back button navigate to specific fragment

Question

I have the navigation drawer menu structure presently setup to allow for going back to the previous fragmnet, with addToBackStack, when selecting the back button as:

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Answer 1

Take a look at this: FragmentManager.popBackStack(int, int)

When you commit your fragment transaction, the method returns an identifier for that transaction. Save that int identifier:

FragmentTransaction xfragmentTransaction = getFragmentManager().beingTransaction();
xfragmentTransaction.replace(R.id.containerView, new MessageTabFragment());
xfragmentTransaction.addToBackStack("MainActivity");
int homeFragmentIdentifier = transaction.commit();

then, in your onBackPressed() method, you can add either of the following lines:

getFragmentManager().popBackStack(homeFragmentIdentifier, 0); // Exclusive

or

getFragmentManager().popBackStack("MainActivity", 0); // Exclusive

This will pop the back stack all the way back to the supplied identifier. Alternatively, if you want to include the homeFragmentIdentifier in the "pop"ing, instead of 0 use FragmentManager.POP_BACK_STACK_INCLUSIVE for the 2nd parameter. You still must call FragmentTransaction.addToBackStack(). According to the docs:

public abstract int commit () ... Returns the identifier of this transaction's back stack entry, if addToBackStack(String) had been called. Otherwise, returns a negative number.

Also, if you set the tag of the fragment when adding it to the backstack, for example:

transaction.add(yourFragment);
transaction.addToBackStack("[YourFragmentTransactionTag]");

You can use the alternate method: FragmentManager.popBackStack(String, int) by supplying the tag you used when adding the transaction to the backstack.

getFragmentManager().popBackStack("[YourFragmentTransactionTag]", 0);