getChildFragmentManager() on programmatically (dynamically) added Fragments?

Question

How to use (or \"Can we use\") getChildFragmentManager() on programmatically (dynamically) added Fragments?

Here is my example.

Answer 1

In conclusion, I want to reference OuterFrag in MainActivity always. And I want OuterFrag act as a placeholder to load different InnerFrags. In short, I want to call getChildFragmentManager() in OuterFrag, when it is added programmatically (dynamically).

If you want this then make your OuterFrag have a container layout as its content and add whatever InnerFrag to that container. The layout file for the OuterFrag will be:

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/fragContainer"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
/>

Of course you could have other views in the layout for the OuterFrag if you want that. Then your addInnerFrag method will be:

public void addInnerFrag() {
        getChildFragmentManager().beginTransaction().add(R.id.fragContainer, new InnerFrag()).commit();
        getChildFragmentManager().executePendingTransactions();
}

The code for adding the OuterFrag to the main activity remains valid.

Answer 2

If you want to call addInnerFrag() within your OuterFrag.java code, you can do it like this:

OuterFrag.java:

@Override
public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
    super.onViewCreated(view, savedInstanceState);
    addInnerFrag();
}