Function render

tools/ngui/static/js/lib/angular.js:14635–14776

()

        scope.$watch(render);

        function render() {
          var optionGroups = {'':[]}, // Temporary location for the option groups before we render them
              optionGroupNames = [''],
              optionGroupName,
              optionGroup,
              option,
              existingParent, existingOptions, existingOption,
              modelValue = ctrl.$modelValue,
              values = valuesFn(scope) || [],
              keys = keyName ? sortedKeys(values) : values,
              groupLength, length,
              groupIndex, index,
              locals = {},
              selected,
              selectedSet = false, // nothing is selected yet
              lastElement,
              element,
              label;

          if (multiple) {
            selectedSet = new HashMap(modelValue);
          }

          // We now build up the list of options we need (we merge later)
          for (index = 0; length = keys.length, index < length; index++) {
               locals[valueName] = values[keyName ? locals[keyName]=keys[index]:index];
               optionGroupName = groupByFn(scope, locals) || '';
            if (!(optionGroup = optionGroups[optionGroupName])) {
              optionGroup = optionGroups[optionGroupName] = [];
              optionGroupNames.push(optionGroupName);
            }
            if (multiple) {
              selected = selectedSet.remove(valueFn(scope, locals)) != undefined;
            } else {
              selected = modelValue === valueFn(scope, locals);
              selectedSet = selectedSet || selected; // see if at least one item is selected
            }
            label = displayFn(scope, locals); // what will be seen by the user
            label = label === undefined ? '' : label; // doing displayFn(scope, locals) || '' overwrites zero values
            optionGroup.push({
              id: keyName ? keys[index] : index,   // either the index into array or key from object
              label: label,
              selected: selected                   // determine if we should be selected
            });
          }
          if (!multiple) {
            if (nullOption || modelValue === null) {
              // insert null option if we have a placeholder, or the model is null
              optionGroups[''].unshift({id:'', label:'', selected:!selectedSet});
            } else if (!selectedSet) {
              // option could not be found, we have to insert the undefined item
              optionGroups[''].unshift({id:'?', label:'', selected:true});
            }
          }

          // Now we need to update the list of DOM nodes to match the optionGroups we computed above
          for (groupIndex = 0, groupLength = optionGroupNames.length;
               groupIndex < groupLength;