onAttach(Activity) deprecated: where I can check if the activity implements callback interface

Question

Before API 23 I used Fragment\'s onAttach methods to get my listener instance, then the reference is cleaned inside onDetach. ex:

@Override
public void onAtt         


        

Answer 1

Check the source code:

/**
 * Called when a fragment is first attached to its context.
 * {@link #onCreate(Bundle)} will be called after this.
 */
public void onAttach(Context context) {
    mCalled = true;
    final Activity hostActivity = mHost == null ? null : mHost.getActivity();
    if (hostActivity != null) {
        mCalled = false;
        onAttach(hostActivity);
    }
}

/**
 * @deprecated Use {@link #onAttach(Context)} instead.
 */
@Deprecated
public void onAttach(Activity activity) {
    mCalled = true;
}

So the onAttach(Activity activity) is called by the onAttach(Context context) if there is a host activity. You can use the onAttach(Activity activity) safely.