Passing data back to previous fragment from curren

问题:

I am Using Navigation Drawer in my app. I have one MainActivity and rest of are Fragments. So the issue is Suppose i have three fragments like A,B,C.

Now in A i have one button and i am sending data from A>B.
For example putSring("datafrom A","datafrom A");
Now in B i receive data From A.
I have one button in B,and i am sending data from B>C.
For example putSring("datafrom B","datafrom B");
Now in C i receive data From B.
Then, I have one Button in C,and sending data from C>B.
For example putSring("datafrom C","datafrom C");

So,seems like in B i am getting data from two different fragments. I tried with all using activity and it work well with startActivityforresult. but how can i manager when all are fragments.

回答1:

When u are sending the data from Fragment A to Fragment B use the same boolean like below:-

FragmentA -> FragmentB

FragmentB ldf = new FragmentB ();
Bundle args = new Bundle();
args.putBoolean("BOOLEAN_VALUE",true);
ldf.setArguments(args);

getFragmentManager().beginTransaction().add(R.id.container, ldf).commit();

And when u are send data from Fragment C to Fragment B use the same BOOLEAN which is used in Fragment A to B like below-

FragmentC -> FragmentB

FragmentB ldf = new FragmentB ();
    Bundle args = new Bundle();
    args.putBoolean("BOOLEAN_VALUE",false);
    ldf.setArguments(args);

    getFragmentManager().beginTransaction().add(R.id.container, ldf).commit();

And in the last we have to check that value is recevied in FragmentB is from where like Fragment A OR FragemntC

FragmentB

   Boolean getValue= getArguments().getBoolean("BOOLEAN_VALUE");  
   if(getValue)
   {
    //VALUE RECEIVED FROM FRAGMENT A
   }
   else
   {
   //VALUE RECEIVED FROM FRAGMENT C
   }

回答2:

You may call setTargetFragment() when you start the Fragment C from B. Example:

FragmentC fragmentC = FragmentC.newInstance();
fragmentC.setTargetFragment(FragmentB.this, REQUEST_CODE);
getFragmentManager().beginTransaction().replace(R.id.container, fragmentC).commit();

and then when you want to pass data back to fragment B from C, you can call the following code:

getTargetFragment().onActivityResult(
                getTargetRequestCode(),
                Activity.RESULT_OK,
                new Intent().putExtra("datafrom C", "datafrom C")
);

and get it from the onActivityResult() method in your fragment B:

@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
    if (requestCode==REQUEST_CODE && resultCode==Activity.RESULT_OK) {
        String datafromC = data.getStringExtra("datafrom C");   
    }
}