Question

我有多种形式的申请表格，当我点击“提交”按钮时，出现错误。我尝试仅使用前4种形式，但仍然有效，我错过了什么吗？谢谢！

颤振：══╡手势引起的异常CA ══════════════════════════════ 扑：处理手势时引发以下NoSuchMethodError：颤动：方法“验证”在null上被调用。颤动：接收者：null 颤抖：尝试调用：validate（）

 final _formKey = GlobalKey<FormState>();
  final _formteleKey = GlobalKey<FormState>();
  final _formStraatKey = GlobalKey<FormState>();
  final _formNumberKey = GlobalKey<FormState>();
  final _formSMOKey = GlobalKey<FormState>();
  final _formSTUKey = GlobalKey<FormState>();
  final _formSWEKey = GlobalKey<FormState>();
  final _formSTHKey = GlobalKey<FormState>();
  final _formSFRKey = GlobalKey<FormState>();
  final _formSSAKey = GlobalKey<FormState>();
  final _formSSUKey = GlobalKey<FormState>();
  final _formEMOKey = GlobalKey<FormState>();
  final _formETUKey = GlobalKey<FormState>();
  final _formEWEKey = GlobalKey<FormState>();
  final _formETHKey = GlobalKey<FormState>();
  final _formEFRKey = GlobalKey<FormState>();
  final _formESAKey = GlobalKey<FormState>();
  final _formESUKey = GlobalKey<FormState>();

  void save() {
    final form = _formKey.currentState;
    final form2 = _formteleKey.currentState;
    final form3 = _formStraatKey.currentState;
    final form4 = _formNumberKey.currentState;
    final form5 = _formSMOKey.currentState;
    final form6 = _formSTUKey.currentState;
    final form7 = _formSWEKey.currentState;
    final form8 = _formSTHKey.currentState;
    final form9 = _formSFRKey.currentState;
    final form10 = _formSSAKey.currentState;
    final form11 = _formSSUKey.currentState;
    final form12 = _formEMOKey.currentState;
    final form13 = _formETUKey.currentState;
    final form14 = _formEWEKey.currentState;
    final form15 = _formETHKey.currentState;
    final form16 = _formEFRKey.currentState;
    final form17 = _formESAKey.currentState;
    final form18 = _formESUKey.currentState;

    if (form.validate()) {
      form.save();

    }

    if (form2.validate()) {
      form2.save();

    }
    if (form3.validate()) {
      form3.save();
    }

    if (form4.validate()) {
      form4.save();
    }
    if (form5.validate()) {
      form5.save();
    }
    if (form6.validate()) {
      form6.save();
    }
    if (form7.validate()) {
      form7.save();
    if (form8.validate()) {
      form8.save();
    }
    if (form9.validate()) {
      form9.save();
    }

    if (form10.validate()) {
      form10.save();
    }
    if (form11.validate()) {
      form11.save();
    }

    if (form12.validate()) {
      form12.save();
    }
    if (form13.validate()) {
      form13.save();
    }

    if (form14.validate()) {
      form14.save();
    }
    if (form15.validate()) {
      form15.save();
    }

    if (form16.validate()) {
      form16.save();
    }
    if (form17.validate()) {
      form17.save();
    }

    if (form18.validate()) {
      form18.save();
    }

    returnCoordinates();

    SUBMIT();
  }

Answer 1

您需要检查是否为所有form变量分配了其中一个为null的值，这就是为什么。它给出了错误

flutter：在处理以下内容时引发了以下NoSuchMethodError：手势：颤抖：方法“ validate”在null上被调用。扑：接收方：空抖动：尝试调用：validate（）

您可以通过调试代码进行验证。

Flutter形式：“方法validate被调用为null”

1 个答案: