DialogFragment调用show()出现异常： IllegalStateException: Can not perform this action after onSaveInstanceState

          这样会出错，因为onSaveInstanceState方法是在该Activity即将被销毁前调用，来保存Activity数据的，如果在保存玩状态后再给它添加Fragment就会出错。解决办法就是把commit()方法替换成 commitAllowingStateLoss()就行了

```

CustomFragmentDialog voucherFragmentDialog = ustomFragmentDialog.newInstance(sourceType);

FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();

fragmentTransaction.add(voucherFragmentDialog,VoucherFragmentDialog.class.getName());

fragmentTransaction.commitAllowingStateLoss();

```