update fixed checkbox when environment variable changes (#3842)

apps/dashboard/app/javascript/launcher_edit.js

@@ -166,16 +166,38 @@ function addInProgressField(event) {
 function updateAutoEnvironmentVariable(event) {
   const aev_name = event.target.value;
   const labelString = event.target.dataset.labelString;
+  const idString = `launcher_auto_environment_variable_${aev_name}`;
+  const nameString = `launcher[auto_environment_variable_${aev_name}]`;
   var input_field = event.target.parentElement.children[2].children[1];
 
   input_field.removeAttribute('readonly');
-  input_field.id = `launcher_auto_environment_variable_${aev_name}`;
-  input_field.name = `launcher[auto_environment_variable_${aev_name}]`;
+  input_field.id = idString;
+  input_field.name = nameString;
 
   if (labelString.match(/Environment( |\s)Variable/)) {
     const label_field = event.target.parentElement.children[2].children[0];
     label_field.innerHTML = `Environment Variable: ${aev_name}`;
   }
+
+  // Update the checkbox so that environment variables can be fixed when created
+  let fixedBoxGroup = event.target.parentElement.children[3].children[0].children[0];
+
+  let checkbox = fixedBoxGroup.children[0];
+  checkbox.id = `${idString}_fixed`;
+  checkbox.name = `launcher[auto_environment_variable_${aev_name}_fixed]`;
+  checkbox.setAttribute('data-fixed-toggler', idString);
+
+  // Update hidden field if attribute is already fixed, otherwise just update label
+  let labelIndex = 2;
+  if(fixedBoxGroup.children.length == 3) {
+    let hiddenField = fixedBoxGroup.children[1];
+    hiddenField.name = nameString;
+  } else {
+    labelIndex = 1;
+  }
+
+  let fixedLabel = fixedBoxGroup.children[labelIndex];
+  fixedLabel.setAttribute('for', `${idString}_fixed`);
 }
 
 function fixExcludeBasedOnSelect(selectElement) {