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angularjsng-options

Customize ng-options selection look


I'm using a ng-options for a select dropdown menu. I would like to use different color for an option depending on a condition:

select(ng-model='myCompany', ng-options='company.code as company.name for company in companies' **if company.active -> text-color=green**)

Is it possible to do that?

Edit (my jade code):

 form(role='form', name='addForm', novalidate, rc-submit="add()")
    .form-group
        div.row
            div.col-xs-12.col-md-3
                select.form-control(ng-model='form.contract', ng-options='contract as contract.number for contract in contracts', options-class="{true:'active',false:'inactive'}[active]")

Solution

  • If you only need to bind the select to string values (not object), you can easily achieve what you want by using ngRepeated <option> elements (instead of ngOptions):

    <select ng-model="color">
      <option value="">--- Select a color ---</option>
      <option value="{{ c }}" style="background-color:{{ c }}" ng-repeat="c in colors">
        {{ c }}
      </option>
    </select>
    

    If you are in for a little custom directive, you can implement it like this:

    app.directive('optionClassExpr', function ($compile, $parse) {
      const NG_OPTIONS_REGEXP = /^\s*([\s\S]+?)(?:\s+as\s+([\s\S]+?))?(?:\s+group\s+by\s+([\s\S]+?))?\s+for\s+(?:([\$\w][\$\w]*)|(?:\(\s*([\$\w][\$\w]*)\s*,\s*([\$\w][\$\w]*)\s*\)))\s+in\s+([\s\S]+?)(?:\s+track\s+by\s+([\s\S]+?))?$/;
      
      return {
        restrict: 'A',
        link: function optionClassExprPostLink(scope, elem, attrs) {
          const optionsExp = attrs.ngOptions;
          if (!optionsExp) return;
          
          const match = optionsExp.match(NG_OPTIONS_REGEXP);
          if (!match) return;
          
          const values = match[7];
          const classExpr = $parse(attrs.optionClassExpr);
          
          scope.$watchCollection(() => elem.children(), newValue => {
            angular.forEach(newValue, child => {
              const child = angular.element(child);
              const val   = child.val();
              if (val) {
                child.attr('ng-class', `${values}[${val}].${attrs.optionClassExpr}`);
                $compile(child)(scope);
              }
            });
          });
        }
      };
    });
    

    And use it like this:

    <select
        ng-model="someObj"
        ng-options="obj as obj.color for obj in objects"
        option-class-expr="color">
    </select>
    

    See, also, this updated short demo.