java android android-layout android-fragments screen-rotation

Redraw fragment after screen rotation with different layout

I am implementing the registration/login part of an application and I am trying to implement it in one activity by using different fragments for login and signup.

I have two different layouts for portrait and landscape mode, which are basically a vertical layout for the portrait one and a horizontal layout for landscape, both with a logo and a FrameLayout containing the fragment (let's consider ony the login one).

The fragment is inflated by an xml resource file and inserted programmatically in the activity onCreate() method in this way:

fragmentManager = this.getFragmentManager();
ViewGroup root = (ViewGroup) getWindow().getDecorView().findViewById(android.R.id.content);
LinearLayout linearLayout = (LinearLayout) root.getChildAt(0);
frameLayout = (FrameLayout) linearLayout.getChildAt(1);
loginFragment = (LoginFragment) fragmentManager.findFragmentByTag("loginFragment");

if (loginFragment == null) {
    // If fragment wasn't saved, create new one
    Log.d("DEBUG", "Fragment is null");
    loginFragment = new LoginFragment();
}
else 
    Log.d("DEBUG", "Fragment is not null");

FragmentTransaction transaction = fragmentManager.beginTransaction();
transaction.replace(frameLayout.getId(), loginFragment, "loginFragment");
transaction.commit();

Everything works fine until I rotate the screen, then I get the following:

java.lang.IllegalStateException: Can't change container ID of fragment LoginFragment{19d136ec #0 id=0x7f090040 loginFragment}: was 2131296320 now 2131296322

I tried to place fragmentManager.executePendingTransactions(); after the commits, but still the same problem. I really don't know what more to try, hope to get some hints.

EDIT: Here are the layout files

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:paddingBottom="@dimen/activity_vertical_margin"
    tools:context=".MainActivity">

<ImageView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/imageView"
    android:layout_gravity="center_horizontal"
    android:src="@drawable/jobsharklogo"
    android:layout_weight="1" />

<FrameLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:id="@+id/frameLayout"
    android:layout_weight="1" />

</LinearLayout>

and

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:orientation="horizontal"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:paddingBottom="@dimen/activity_vertical_margin"
    tools:context=".MainActivity">

<ImageView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/imageView2"
    android:layout_gravity="center_vertical"
    android:src="@drawable/jobsharklogo" />

<FrameLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:id="@+id/frameLayout2"
    android:layout_weight="1" />

</LinearLayout>

And LoginFragment code:

public class LoginFragment extends Fragment implements View.OnClickListener {
// TODO: Rename parameter arguments, choose names that match
// the fragment initialization parameters, e.g. ARG_ITEM_NUMBER
private static final String ARG_PARAM1 = "param1";
private static final String ARG_PARAM2 = "param2";

// TODO: Rename and change types of parameters
private String mParam1;
private String mParam2;

private OnLoginFragmentInteractionListener mListener;

/**
 * Use this factory method to create a new instance of
 * this fragment using the provided parameters.
 *
 * @param param1 Parameter 1.
 * @param param2 Parameter 2.
 * @return A new instance of fragment LoginFragment.
 */
// TODO: Rename and change types and number of parameters
public static LoginFragment newInstance(String param1, String param2) {
    LoginFragment fragment = new LoginFragment();
    Bundle args = new Bundle();
    args.putString(ARG_PARAM1, param1);
    args.putString(ARG_PARAM2, param2);
    fragment.setArguments(args);
    return fragment;
}

public LoginFragment() {
    // Required empty public constructor
}

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    if (getArguments() != null) {
        mParam1 = getArguments().getString(ARG_PARAM1);
        mParam2 = getArguments().getString(ARG_PARAM2);
    }
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // Inflate the layout for this fragment
    View view = inflater.inflate(R.layout.fragment_login, container, false);
    LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT, 1);
    params.gravity = Gravity.CENTER;
    view.setLayoutParams(params);
    Button loginButton = (Button) view.findViewById(R.id.loginButton);
    Button signupButton = (Button) view.findViewById(R.id.signupButton);
    loginButton.setOnClickListener(this);
    signupButton.setOnClickListener(this);
    return view;
}

public void onClick(View button) {
    if (mListener != null) {
        mListener.onLoginFragmentInteraction(button.getId());
    }
}

@Override
public void onAttach(Activity activity) {
    super.onAttach(activity);
    try {
        mListener = (OnLoginFragmentInteractionListener) activity;
    } catch (ClassCastException e) {
        throw new ClassCastException(activity.toString()
                + " must implement OnFragmentInteractionListener");
    }
}

@Override
public void onDetach() {
    super.onDetach();
    mListener = null;
}

/**
 * This interface must be implemented by activities that contain this
 * fragment to allow an interaction in this fragment to be communicated
 * to the activity and potentially other fragments contained in that
 * activity.
 * <p/>
 * See the Android Training lesson <a href=
 * "http://developer.android.com/training/basics/fragments/communicating.html"
 * >Communicating with Other Fragments</a> for more information.
 */
public interface OnLoginFragmentInteractionListener {

    public void onLoginFragmentInteraction(int id);
}

}

Solution

The trouble is probably that you're trying to replace a fragment you added via XML.

See: IllegalStateException when replacing a Fragment for the discussion.

Edit 2:

I use landscape mode also, and am able to rotate this and change layout. Ok, I implemented your code (with what I could figure out from your code). I only changed the way I located the elements by using findViewBy().

In the activity:

public class LoginActivity extends Activity implements LoginFragment.OnLoginFragmentInteractionListener {

private FragmentManager fragmentManager;
private FrameLayout frameLayout;
private LoginFragment loginFragment;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    fragmentManager = this.getFragmentManager();
    ViewGroup root = (ViewGroup) getWindow().getDecorView().findViewById(android.R.id.content);
    frameLayout = (FrameLayout) root.findViewById(R.id.frameLayout);
    loginFragment = (LoginFragment) fragmentManager.findFragmentByTag("loginFragment");

    if (loginFragment == null) {
        // If fragment wasn't saved, create new one
        Log.d("DEBUG", "Fragment is null");
        loginFragment = new LoginFragment().newInstance("param1", "param2");
    }
    else
        Log.d("DEBUG", "Fragment is not null");

    FragmentTransaction transaction = fragmentManager.beginTransaction();
    transaction.replace(frameLayout.getId(), loginFragment, "loginFragment");
    transaction.commit();
}

@Override
public void onLoginFragmentInteraction(int id) {
    Log.e("DEBuG", "id: "+id);
}

}

where main.xml is:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
          xmlns:tools="http://schemas.android.com/tools"
          android:orientation="vertical"
          android:id="@+id/linear"
          android:layout_width="match_parent"
          android:layout_height="match_parent"
          android:paddingLeft="@dimen/activity_horizontal_margin"
          android:paddingRight="@dimen/activity_horizontal_margin"
          android:paddingTop="@dimen/activity_vertical_margin"
          android:paddingBottom="@dimen/activity_vertical_margin"
          tools:context=".MainActivity"
          android:background="#f0498a">

<FrameLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/frameLayout"
        android:layout_weight="1" />

Clicking on the buttons in any of the rotation modes, I got:

E/DEBuG﹕ id: 2131296322
E/DEBuG﹕ id: 2131296321

The xml I used for landscape mode (put in layout-land

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
          xmlns:tools="http://schemas.android.com/tools"
          android:orientation="horizontal"
          android:id="@+id/linear"
          android:layout_width="match_parent"
          android:layout_height="match_parent"
          android:paddingLeft="@dimen/activity_horizontal_margin"
          android:paddingRight="@dimen/activity_horizontal_margin"
          android:paddingTop="@dimen/activity_vertical_margin"
          android:paddingBottom="@dimen/activity_vertical_margin"
          tools:context=".MainActivity"
          android:background="@color/material_blue_grey_900">

<FrameLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:id="@+id/frameLayout"
        android:layout_weight="1" />

<Button
        android:id="@+id/loginButton"
        android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="login"/>


<Button
        android:id="@+id/signupButton"
        android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="sing in"/>


<ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/imageView2"
        android:layout_gravity="center_vertical"
        android:src="@drawable/jobsharklogo" />

and portrait mode (just in layout folder)

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
          xmlns:tools="http://schemas.android.com/tools"
          android:orientation="vertical"
          android:id="@+id/linear"
          android:layout_width="match_parent"
          android:layout_height="match_parent"
          android:paddingLeft="@dimen/activity_horizontal_margin"
          android:paddingRight="@dimen/activity_horizontal_margin"
          android:paddingTop="@dimen/activity_vertical_margin"
          android:paddingBottom="@dimen/activity_vertical_margin"
          tools:context=".MainActivity"
          android:background="#f0498a">

<FrameLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/frameLayout"
        android:layout_weight="1" />

<Button
    android:id="@+id/loginButton"
    android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="login"/>


<Button
        android:id="@+id/signupButton"
        android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="sing in"/>

<ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/imageView"
        android:layout_gravity="center_horizontal"
        android:src="@drawable/jobsharklogo"
        android:layout_weight="1" />