Why does form.getEditor('CheckInToDate') return undefined when using a custom template in DevExpress dxForm?

The problem is that using a custom template prevents dxForm from automatically registering the editor as expected. When you override a form item’s template, the dxForm’s internal mechanism that links a dataField to its corresponding editor instance is bypassed, so getEditor("CheckInToDate") returns undefined.

To resolve this issue, you have two main options:

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Option 1: Use dxForm’s Built-In Editor Registration

Avoid a custom template for the second editor. Let dxForm create the editor automatically by specifying the dataField, editorType, and additional options via editorOptions. For example:

JAVASCRIPTCopied
$(function () {
  const formData = {};

  const form = $("#formContainer").dxForm({
    formData: formData,
    items: [
      {
        itemType: "group",
        colCount: 2,
        items: [
          {
            dataField: "CheckInFromDate",
            label: { text: "Check-In from" },
            editorType: "dxDateBox",
            editorOptions: {
              showClearButton: true,
              displayFormat: "dd/MM/yyyy",
              onValueChanged: function (e) {
                const minDate = e.value;
                // Now getEditor returns a valid instance
                form.getEditor("CheckInToDate").option("min", minDate);
                form.getEditor("CheckInToDate").option("disabled", !minDate);
              }
            },
            validationRules: [
              {
                type: "required",
                message: "At least one valid date pair is required."
              }
            ]
          },
          {
            dataField: "CheckInToDate",
            label: { text: "To" },
            editorType: "dxDateBox",
            editorOptions: {
              showClearButton: true,
              displayFormat: "dd/MM/yyyy",
              disabled: true
            },
            validationRules: [
              {
                type: "required",
                message: "At least one valid date pair is required."
              }
            ]
          }
        ]
      }
    ]
  }).dxForm("instance");
});

In this configuration, dxForm automatically registers both editors. Calling form.getEditor("CheckInToDate") inside the onValueChanged event of the first date box will return a valid instance.

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Option 2: Manually Register the Editor Instance When Using a Custom Template

If you must use a custom template for custom rendering purposes, you can manually store the editor instance (for example, in a shared variable or on the form’s data). One way is to use the onInitialized callback inside the custom template’s widget initialization:

JAVASCRIPTCopied
$(function () {
  const formData = {}; 
  let checkInToDateEditor = null; // variable to hold CheckInToDate editor instance

  const form = $("#formContainer").dxForm({
    formData: formData,
    items: [
      {
        itemType: "group",
        colCount: 2,
        items: [
          {
            dataField: "CheckInFromDate",
            label: { text: "Check-In from" },
            template: function (data, $itemElement) {
              $("<div>").dxDateBox({
                showClearButton: true,
                displayFormat: "dd/MM/yyyy",
                onValueChanged: function (e) {
                  const minDate = e.value;
                  if (checkInToDateEditor) {
                    checkInToDateEditor.option("min", minDate);
                    checkInToDateEditor.option("disabled", !minDate);
                  }
                },
                // optional: onInitialized if you need to track the instance too
                onInitialized: function (e) {
                  // Optionally, store this instance if needed.
                }
              }).appendTo($itemElement);
            },
            validationRules: [
              {
                type: "required",
                message: "At least one valid date pair is required."
              }
            ]
          },
          {
            dataField: "CheckInToDate",
            label: { text: "To" },
            template: function (data, $itemElement) {
              $("<div>").dxDateBox({
                showClearButton: true,
                displayFormat: "dd/MM/yyyy",
                disabled: true,
                onInitialized: function (e) {
                  // Manually store the instance for later use.
                  checkInToDateEditor = e.component;
                }
              }).appendTo($itemElement);
            },
            validationRules: [
              {
                type: "required",
                message: "At least one valid date pair is required."
              }
            ]
          }
        ]
      }
    ]
  }).dxForm("instance");
});

In this approach, you manually capture the instance of the CheckInToDate editor using the onInitialized callback. Then, when the first date box’s onValueChanged fires, you can refer to the stored checkInToDateEditor variable to update its options.

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Summary

• When using custom templates, dxForm does not automatically register the widget instance.
• To get a valid editor instance via getEditor(), avoid overriding the template by using editorType and editorOptions.
• If a custom template is necessary, capture the widget instance manually (e.g., via onInitialized) and reference it later.

Either option will allow you to enable/disable the second date editor dynamically based on the first date editor’s value.