Question

我得到了 java.lang.IllegalStateException: Can not perform this action after onSaveInstanceState

在我的代码中，我搜索了statckoverflow，我得到了以下代码作为解决方案。

现在我没有得到IllegalStateException，但问题是..代码正在清除整个堆栈跟踪。但我想只弹出Backstack中的最后一个事务/条目。该怎么做??

            if (getSupportFragmentManager().getBackStackEntryCount() > 0) {
                getSupportFragmentManager().popBackStack(getSupportFragmentManager().getBackStackEntryAt(0).getId(), FragmentManager.POP_BACK_STACK_INCLUSIVE);
            }

如何仅弹出Backstack中的最后一个事务/条目？

我如何添加到堆栈的代码：

      fragmentManager.beginTransaction().
                setCustomAnimations(R.anim.slide_in_left, R.anim.slide_in_left, R.anim.slide_out_right, R.anim.slide_out_right).
                replace(R.id.content_frame, pageFragment, currentItem).
                addToBackStack(currentItem).
                commit();

Answer 1

弹出最后一个交易条目：

int last = getActivity().getSupportFragmentManager().getBackStackEntryCount() - 1
FragmentManager.BackStackEntry entry = getSupportFragmentManager().getBackStackEntryAt(last);
String tag = entry.getName();
Fragment fragment = getSupportFragmentManager().findFragmentByTag("last");  //get the last fragment

同样在交易期间，您必须添加标签..

fragmentTransaction.addToBackStack("last");

您还可以使用popBackStackImmediate弹出最后一个片段：

getSupportFragmentManager().popBackStackImmediate(getSupportFragmentManager().getBackStackEntryAt(last), FragmentManager.POP_BACK_STACK_INCLUSIVE);

使用标签使用从BackStack弹出片段：

 getSupportFragmentManager().popBackStack ("last", FragmentManager.POP_BACK_STACK_INCLUSIVE);

Answer 2

对于此错误：

java.lang.IllegalStateException：之后无法执行此操作的onSaveInstanceState

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弹出backstack而不会导致illegalStateException

2 个答案: