java - 屏幕旋转后以不同布局重绘 fragment

Question

我正在实现应用程序的注册/登录部分，并尝试通过使用不同的 fragment 进行登录和注册来在一个 Activity 中实现它。

我有两种不同的纵向和横向布局，基本上是纵向布局的垂直布局和横向的水平布局，两者都带有 Logo 和包含 fragment 的 FrameLayout(让我们只考虑登录布局)。

该 fragment 由 xml 资源文件扩展，并以编程方式插入到 Activity onCreate() 方法中，如下所示:

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();

一切正常，直到我旋转屏幕，然后我得到以下结果:

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

我尝试将 fragmentManager.executePendingTransactions(); 放置在提交之后，但仍然存在同样的问题。我真的不知道还要尝试什么，希望得到一些提示。

编辑:这是布局文件

<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>

和

<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>

和LoginFragment代码:

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);
}

}

Answer 1

问题可能是您正在尝试替换通过 XML 添加的 fragment 。

参见:IllegalStateException when replacing a Fragment供讨论。

编辑2:

我也使用横向模式，并且能够旋转它并更改布局。好的，我实现了你的代码(用我可以从你的代码中找出的内容)。我只是使用 findViewBy() 更改了定位元素的方式。

在 Activity 中:

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);
}

}

其中 main.xml 是:

<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" />

单击任何旋转模式下的按钮，我得到:

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

我用于横向模式的 xml(放入 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" />

和纵向模式(仅在 layout 文件夹中)

<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" />