动态替换片段时的RuntimeException

Question

我一直在尝试在我的应用程序中动态替换一个片段，但这样做时，我一直会遇到RuntimeException，因为它找不到应该添加片段的容器ID。我尝试过在类似线程上找到的每一个解决方案，从干净的构建到使用ChildFragmentManager，但仍然有相同的错误。最奇怪的是，当我在onCreate中没有指定任何容器时，一切都很顺利，但一旦指定了容器，应用程序就会崩溃。以下是代码和堆栈跟踪：

堆栈跟踪：

E/AndroidRuntime: FATAL EXCEPTION: main
                  Process: com.example.user.onceuponatime, PID: 23668
                  java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.user.onceuponatime/com.example.user.onceuponatime.activity.AuthentificationActivity}: java.lang.IllegalArgumentException: No view found for id 0x7f0d007f (com.example.user.onceuponatime:id/fragment_container) for fragment SignInFragment{42d6c688 #0 id=0x7f0d007f signinfragment}
                      at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2394)
                      at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2452)
                      at android.app.ActivityThread.access$900(ActivityThread.java:172)
                      at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1302)
                      at android.os.Handler.dispatchMessage(Handler.java:102)
                      at android.os.Looper.loop(Looper.java:136)
                      at android.app.ActivityThread.main(ActivityThread.java:5586)
                      at java.lang.reflect.Method.invokeNative(Native Method)
                      at java.lang.reflect.Method.invoke(Method.java:515)
                      at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1268)
                      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1084)
                      at dalvik.system.NativeStart.main(Native Method)
                   Caused by: java.lang.IllegalArgumentException: No view found for id 0x7f0d007f (com.example.user.onceuponatime:id/fragment_container) for fragment SignInFragment{42d6c688 #0 id=0x7f0d007f signinfragment}
                      at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1293)
                      at android.support.v4.app.FragmentManagerImpl.moveFragmentToExpectedState(FragmentManager.java:1528)
                      at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1595)
                      at android.support.v4.app.BackStackRecord.executeOps(BackStackRecord.java:757)
                      at android.support.v4.app.FragmentManagerImpl.executeOps(FragmentManager.java:2355)
                      at android.support.v4.app.FragmentManagerImpl.executeOpsTogether(FragmentManager.java:2146)
                      at android.support.v4.app.FragmentManagerImpl.optimizeAndExecuteOps(FragmentManager.java:2098)
                      at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:2008)
                      at android.support.v4.app.FragmentController.execPendingActions(FragmentController.java:388)
                      at android.support.v4.app.FragmentActivity.onStart(FragmentActivity.java:607)
                      at android.support.v7.app.AppCompatActivity.onStart(AppCompatActivity.java:178)
                      at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1177)
                      at android.app.Activity.performStart(Activity.java:5461)
                      at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2367)
                      at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2452) 
                      at android.app.ActivityThread.access$900(ActivityThread.java:172) 
                      at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1302) 
                      at android.os.Handler.dispatchMessage(Handler.java:102) 
                      at android.os.Looper.loop(Looper.java:136) 
                      at android.app.ActivityThread.main(ActivityThread.java:5586) 
                      at java.lang.reflect.Method.invokeNative(Native Method) 
                      at java.lang.reflect.Method.invoke(Method.java:515) 
                      at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1268) 
                      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1084) 
                      at dalvik.system.NativeStart.main(Native Method) 

认证活动：

public class AuthentificationActivity extends AppCompatActivity implements SignInFragment.SignInFragmentCallBack
        ,SignUpFragment.SignUpFragmentCallBack{

    public static final String SIGNINFRAGMENT_TAG = "signinfragment";
    public static final String SIGNUPFRAGMENT_TAG = "signupfragment";

    public static final int SIGNIN_FRAGMENT_ID = 846464;
    public static final int SIGNUP_FRAGMENT_ID = 125478;
    public static final int LOST_PWD_FRAGMENT_ID = 85546;

    private FragmentManager mFragmentManager;
    private SignInFragment mSignInFragment;
    private SignUpFragment mSignUpFragment;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_authentification);


        mSignInFragment = SignInFragment.getInstance();

        mFragmentManager = getSupportFragmentManager();
        FragmentTransaction fragmentTransaction = mFragmentManager.beginTransaction();


        fragmentTransaction.add(R.id.fragment_container,mSignInFragment,SIGNINFRAGMENT_TAG);
        fragmentTransaction.addToBackStack(null);
        fragmentTransaction.commit();


    }

    @Override
    public void onFragmentSwapRequested(int FragmentId) {

        mFragmentManager = this.getSupportFragmentManager();

        FragmentTransaction fgTransaction = mFragmentManager.beginTransaction();

        switch(FragmentId) {
            case SIGNUP_FRAGMENT_ID:
                if(!isFinishing()) {
                    mSignUpFragment = (SignUpFragment) mFragmentManager.findFragmentByTag(SIGNUPFRAGMENT_TAG);
                    if (mSignUpFragment == null) {
                        mSignUpFragment = SignUpFragment.getInstance();
                        fgTransaction.replace(R.id.fragment_container, mSignUpFragment, SIGNUPFRAGMENT_TAG);
                    } else {
                        fgTransaction.show(mSignUpFragment);
                    }
                    fgTransaction.addToBackStack(null);
                    fgTransaction.commit();
                }
                break;
            case LOST_PWD_FRAGMENT_ID:
                break;


        }



    }
}

重要片段：

public class SignInFragment extends Fragment {
    FragmentSignInBinding signInBinding;

    private CoordinatorLayout mCoordinatorLayout;
    private EditText mEmailEdit,mPasswordEdit;
    private Button btnSignIn,btnSignUp,btnLostPwd;
    private ProgressBar mProgressBar;

    private FirebaseAuth mAuth;

    private SignInFragmentCallBack mCallBack;



    public interface SignInFragmentCallBack {
        void onFragmentSwapRequested(int FragmentId);
    }

    public SignInFragment() {}


    public static SignInFragment getInstance() {
        return new SignInFragment();
    }

    @Override
    public void onAttach(Context context) {
        super.onAttach(context);
        try {
            mCallBack = (SignInFragmentCallBack) context;
        } catch(ClassCastException e) {
            throw new ClassCastException(context.toString() + " must implements SignInCallaback");
        }
        Toast.makeText(context,mCallBack.toString(),Toast.LENGTH_LONG).show();
    }

    @Override
    public void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        signInBinding = DataBindingUtil.setContentView(getActivity(),R.layout.fragment_sign_in);
        mEmailEdit = signInBinding.emailSignin;
        mPasswordEdit = signInBinding.passwordSignin;
        mProgressBar = signInBinding.progressBarSignIn;
        btnSignIn = signInBinding.signInButton;
        btnSignUp = signInBinding.signUpButton;
        btnLostPwd = signInBinding.passwordReset;
        mCoordinatorLayout = signInBinding.coordinatorSignin;



        mAuth = FirebaseAuth.getInstance();



        btnSignIn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                signInAction();
            }
        });

        btnSignUp.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if(mCallBack instanceof SignInFragmentCallBack)
                mCallBack.onFragmentSwapRequested(AuthentificationActivity.SIGNUP_FRAGMENT_ID);
            }
        });

        btnLostPwd.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if(mCallBack instanceof SignInFragmentCallBack)
                mCallBack.onFragmentSwapRequested(AuthentificationActivity.LOST_PWD_FRAGMENT_ID);
            }
        });


    }

    private void signInAction() {
        String email = mEmailEdit.getText().toString().trim();
        final String password = mPasswordEdit.getText().toString().trim();

        if(TextUtils.isEmpty(email)) {
            Snackbar.make(mCoordinatorLayout,getString(R.string.no_email_entered),Snackbar.LENGTH_LONG).show();
            return;
        }

        if(TextUtils.isEmpty(password)) {
            Snackbar.make(mCoordinatorLayout,getString(R.string.no_password_entered),Snackbar.LENGTH_LONG).show();
            return;
        }

        mProgressBar.setVisibility(View.VISIBLE);
        mAuth.signInWithEmailAndPassword(email,password).addOnCompleteListener(getActivity(), new OnCompleteListener<AuthResult>() {
            @Override
            public void onComplete(@NonNull Task<AuthResult> task) {
                mProgressBar.setVisibility(View.GONE);
                if(task.isSuccessful()) {
                    Snackbar.make(mCoordinatorLayout,getString(R.string.login_success),Snackbar.LENGTH_LONG).show();
                    startActivity(new Intent(getActivity(), MainActivity.class));
                    getActivity().finish();
                }
                else
                {
                    Snackbar.make(mCoordinatorLayout,getString(R.string.login_failed),Snackbar.LENGTH_LONG).show();

                }
            }
        });
    }


    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        return inflater.inflate(R.layout.fragment_sign_in,container,false);
    }

    @Override
    public void onResume() {
        super.onResume();
        mProgressBar.setVisibility(View.GONE);
    }
}

活动认证。xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/activity_authentification"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.example.user.onceuponatime.activity.AuthentificationActivity">

<FrameLayout
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:id="@+id/fragment_container"/>



</LinearLayout>

编辑：我尝试检查R. java以查看Id是否被搞砸了，但似乎一切都很好，fragment_containerid明显存在。我还尝试清理项目，但正如我所料，这并没有改变任何事情。我尝试用替换（）替换add，但仍然是相同的错误，除了当我使用android时。R.id.container作为容器。我正在使用数据绑定，也许这是冲突的原因？

EDIT2：我已经创建了一个新项目，在那里我做了相同的事务，但有一个简单的片段显示了一个简单的文本视图，而且一切似乎都很好，没有崩溃的迹象。所以我试着删除片段中的模糊项，比如回调，但我还是犯了同样的错误。数据绑定似乎不是问题，因为我尝试不使用它，但仍然得到相同的堆栈跟踪。

谢谢你的帮助。

Answer 1

代码中的问题是，您试图将signInFragmentUI绑定到onCreate方法中的行为，但是这个方法在onCreateView之前调用，正如您在片段生命周期中看到的那样。

如果您在onCreateView中移动onCreate方法的内容，或者以后调用的任何方法，您将不会再发生此崩溃。