Trying to call a fragment method from parent activity but the method is not being resolved

Question

I tried the solution here:

Calling a Fragment method from a parent Activity

But it didn't work for me.

I have this method in my fragment

 public void showbutton()
    {
        sup.setEnabled(true);
    }

and I'm using this in the parent activity

Fragment fragment = (Fragment) getFragmentManager().findFragmentById(R.id.fragment);
fragment.showbutton();

I'm sure it's a silly mistake, I'm still new to Android so forgive me.

The `Fragment` class does not have your `showbutton()` method. Your specific subclass of `Fragment` does. — Mike M., Jan 17 '18 at 06:53
Is there a way for me to call the showbutton method from my fragment sub class in the parent activity? @Mike M. — Manan Adhvaryu, Jan 17 '18 at 06:55
Declare and assign `fragment` as your specific subclass, rather than just `Fragment`. — Mike M., Jan 17 '18 at 06:56

score 2 · Accepted Answer · answered Jan 17 '18 at 07:01

2

Use callback to communicate from fragment to Activity.

public interface UserAction {
void showButton();
}

In the Fragment implement the Interface

@Override
public void showButton() {
        sup.setEnabled(true);
}

Then in your activity just call

UserAction mUserAction = getFragmentManager().findFragmentById(R.id.fragment);
mUserAction.showButton();

answered Jan 17 '18 at 07:01

pratham kesarkar

3,770
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1

you can even add more functions to this interface for communication between activity and fragments – pratham kesarkar Jan 17 '18 at 07:17

score 1 · Answer 2 · answered Jan 17 '18 at 06:56

Firstly, make sure you are accessing the correct FragmentManager, verify that you need to call either getFragmentManager() or getSupportFragmentManager().

Secondly, you should cast the Fragment to your type. That is,

MyFragment fragment = (MyFragment) getFragmentManager().findFragmentById(R.id.fragment);
fragment.showbutton();

score 0 · Answer 3 · answered Jan 17 '18 at 06:55

0

I think you should typecast using Fragment Name.

i.e

YourFragment fragment = (YourFragment) getFragmentManager().findFragmentById(R.id.fragment);
fragment.showbutton();

answered Jan 17 '18 at 06:55

Avinash Verma

2,572
1
18
22

score 0 · Answer 4 · answered Jan 17 '18 at 06:57

This issue is regarding to fragment life cycle. You are trying to invoke method of fragment which is closed by android OS. You need to create bool in your fragment and set that to false normally but when you need to show button just create that fragment and load that and update your bool to true.Later on check if that bool is true enable your button else disable it. Happy Coding!

Trying to call a fragment method from parent activity but the method is not being resolved

4 Answers4