等待FragmentTransaction动画完成

Question

我有一个包含EditText和Button的活动。只要在EditText中输入一个数字并单击按钮，就会显示一个片段(覆盖整个屏幕)两秒钟，然后将其删除。两个事务都调用了showCustomAnimations()。在代码中，在remove FragmentTransaction上调用commit()之后，通过showSoftInput()显示了软键盘。

我面临的问题是:当remove动画正在运行时，片段已经滑出屏幕80%，软键盘弹出。现在，如果你快速输入一个数字并按下按钮，应用程序就会崩溃，因为之前的动画仍在运行。

我已经看到了几个答案，但我发现它们不够充分或不起作用。任何对commitNow()或executePendingTransitions()的调用都无济于事，因为事务已提交，问题是动画在提交后仍在运行。用于检查活动是否可见的方法getVisibleUserHint()已弃用。

代码：

TrueFragment trueFragment = new TrueFragment();

fabNext.setOnClickListener(new View.OnClickListener() {  //fabNext is my button
        @Override
        public void onClick(View v) {

            fabNext.setEnabled(false);  //blocking button to avoid clicking (... further code for this...)
            inputManager.hideSoftInputFromWindow(constraintLayoutCalculating.getWindowToken(), 0);  //hide Keyboard

            final FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();  //FragmentTransaction to show the Fragment
            transaction.setCustomAnimations(R.animator.slide_in, 0);
            transaction.add(R.id.constraintLayoutCalculating, trueFragment);
            transaction.commitAllowingStateLoss();
            getSupportFragmentManager().executePendingTransactions();

            final Handler handler = new Handler();
            handler.postDelayed(new Runnable() {
                @Override
                public void run() {

                    FragmentTransaction transaction2 = getSupportFragmentManager().beginTransaction();  //FragmentTransaction to remove the Fragment
                    transaction2.setCustomAnimations(0, R.animator.slide_out);
                    transaction2.remove(trueFragment);
                    transaction2.commitAllowingStateLoss();
                    editText.setText(null);  //reset EditText
                    editText.requestFocus();
                    textInputLayout.setError(null);
                    inputManager.showSoftInput(editText, InputMethodManager.SHOW_IMPLICIT);  //show Keyboard
                    fabNext.setEnabled(true);  //reenable button at the end - Problem: Button made clickable again, even if the remove FragmentTransaction animation hasn't finished

               }
         }, 1000);
}

这就是我得到的崩溃。在StackOverflow上搜索一下，我发现它与启动一个FragmentTransaction有关，而另一个还没有完成。

 --------- beginning of crash
2020-02-17 10:27:29.787 23467-23467/my.top.secretpreciousname E/AndroidRuntime: FATAL EXCEPTION: main
    my.top.secretpreciousname, PID: 23467
    java.lang.IllegalStateException: Restarter must be created only during owner's initialization stage
        at androidx.savedstate.SavedStateRegistryController.performRestore(SavedStateRegistryController.java:58)
        at androidx.fragment.app.Fragment.performCreate(Fragment.java:2585)
        at androidx.fragment.app.FragmentManagerImpl.moveToState(FragmentManagerImpl.java:838)
        at androidx.fragment.app.FragmentManagerImpl.moveFragmentToExpectedState(FragmentManagerImpl.java:1238)
        at androidx.fragment.app.FragmentManagerImpl.moveToState(FragmentManagerImpl.java:1303)
        at androidx.fragment.app.BackStackRecord.executeOps(BackStackRecord.java:439)
        at androidx.fragment.app.FragmentManagerImpl.executeOps(FragmentManagerImpl.java:2079)
        at androidx.fragment.app.FragmentManagerImpl.executeOpsTogether(FragmentManagerImpl.java:1869)
        at androidx.fragment.app.FragmentManagerImpl.removeRedundantOperationsAndExecute(FragmentManagerImpl.java:1824)
        at androidx.fragment.app.FragmentManagerImpl.execPendingActions(FragmentManagerImpl.java:1727)
        at androidx.fragment.app.FragmentManagerImpl.executePendingTransactions(FragmentManagerImpl.java:183)
        at my.top.secretpreciousname.CalculatingActivity$1.onClick(CalculatingActivity.java:254)
        at android.view.View.performClick(View.java:7339)
        at my.top.secretpreciousname.CalculatingActivity$2.onEditorAction(CalculatingActivity.java:320)
        at android.widget.TextView.doKeyDown(TextView.java:8617)
        at android.widget.TextView.onKeyDown(TextView.java:8486)
        at android.view.KeyEvent.dispatch(KeyEvent.java:3359)
        at android.view.View.dispatchKeyEvent(View.java:13312)
        at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1912)
        at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1912)
        at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1912)
        at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1912)
        at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1912)
        at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1912)
        at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1912)
        at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1912)

有没有很好的解决方案？提前感谢您的帮助。

Answer 1

结果是，我必须添加这一行

transaction2.addToBackStack(null);

添加到动画FragmentTransaction，以实现在前一个事务完成其动画之前触发新事务时，它不会崩溃。我仍然不确定这是否可以被认为是一个有效的解决方案，因为实际上我不想使用这些片段的backstack功能，所以我不得不在每次事务后暂时阻止back按钮或刷新Backstack。