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javascripthtmlangularjsangularjs-materialmd-select

I want a blank option with md-select and I want it not to validate when required


I'm using Angular Material and md-select and I would like to make a blank option such that when you select it, you have no value in the select. In the case that I make it required, then I would like this option returning false at the check.

Here's a demo: https://plnkr.co/edit/FZ8xt5ZCRJY3fFMh3fFU?p=preview

<html>
  <head>
    <meta charset="utf-8" />
    <title>AngularJS Plunker</title>
    <script>document.write('<base href="' + document.location + '" />');</ript>
    <link rel="stylesheet" href="style.css" />
    <script data-require="[email protected]" src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.19/angular.min.js" data-semver="1.2.19"></script>
    <script src="app.js"></script>
  </head>

  <body ng-controller="MainCtrl">
    <form>
      <select ng-model="selectedValue2" required >
        <option ng-repeat="option in options['id'] | orderBy: 'id'" ng-value="option.value">{{option.name}}</option>
      </select>
      <button type="submit">Submit</button>
    </form>
  </body>  
</html>

My situation is more complex, so I don't want a workaround, I just would like a way to make the required working when I select the blank option.


Solution

  • QUESTION CHANGED AFTER ASKING. Not originally about md-select so there may be a better way to do this. All you need to do is add this option to your md-select:

    <md-option value=""></md-option>
    

    And remove the blank entry from your object.

    HTML

    <select ng-model="selectedValue2" required >
        <option value=""></option>
        <option ng-repeat="option in options['id'] | orderBy: 'id'" ng-value="option.value">{{option.name}}</option>
    </select>
    

    JavaScript

    $scope.options = {id : [
        {name : 'World', value : 'World', id:3},
        {name : 'qweqwe', value : 'qweqwe', id:1},
        {name : 'rwerasdf', value : 'rwerasdf', id:2}
    ]}
    

    This would be enough if you were using a regular select, but md-select considers the null value to satisfy the required attribute so you need extra work.

    In your select, add a function checkNull to run onchange:

     ng-change="checkNull()"
    

    Then add it to your scope:

    $scope.checkNull = function(){
        if(typeof $scope.selectedValue2 === "undefined"){
            $scope.myform.myselect.$setValidity("required", false);
        }
    };
    

    Working Fiddle