这个问题的其他情况都没有解决我的问题。我有一个片段出现在事务序列的末尾。它旨在在其中包含的 <div class="row">
<div class="col-md-3 mb-3">
<label for="pi-ida">Composição de Produtos Internos</label>
<select name="estrutura" multiple id="id_estrutura" required>
{%for prod in lista_pi%}
<option value="{{prod.id}}">{{prod.produto_desc}}</option>
{% endfor %}
</select>
</div>
</div>
<hr class="mb-4">
<button class="btn btn-primary btn-lg btn-block" type="submit">Cadastrar</button>
完成时关闭该应用：
Timer}
每当片段离开时，都会调用 var terminalTimer: Timer? = null
class TerminalFragment : Fragment() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
}
override fun onCreateView(
inflater: LayoutInflater, container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_terminal, container, false)
}
override fun onStart() {
super.onStart()
initUi()
startCountDown()
}
override fun onStop() {
super.onStop()
AppLog.i(TAG, "onStop()")
stopCountDown()
}
private fun startCountDown() {
if (terminalTimer == null) {
terminalTimer = Timer()
terminalTimer!!.schedule(object : TimerTask() {
override fun run() {
AppLog.i(TAG, "Terminal countdown finished")
{
activity?.finish()
}
}, 5000)
}
}
private fun stopCountDown() {
AppLog.i(TAG, "stopCountDown()")
terminalTimer?.cancel()
terminalTimer?.purge()
terminalTimer = null
}
private fun returnToStart() {
AppLog.i(TAG, "returnToStart()")
(context as MainActivity).restartFlow() // calls popBackStackImmediate() for every fragment in the backstack, returning user to the beginning of their flow
}
companion object {
@JvmStatic
fun newInstance(terminalType: String, amountLoaded: Double) =
TerminalFragment().apply {
arguments = Bundle().apply {
}
}
}
，但有时它会以某种方式保留下来并从另一个Fragment中关闭应用程序。使用日志，我还发现有时该计时器似乎有2个实例。我如何确保此倒计时在此片段之外永远不会活动，并且在片段的onStop（）中被取消/销毁？