I want a blank option with md-select and I want it not to validate when required
Question
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="angular.js@1.2.x" 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.
2 answers
solution1
1 ACCPTED 2018-10-05 10:12:03
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);
}
};
solution2
1 2018-10-08 08:21:50
尝试添加以下代码段：
<md-option ng-value disabled>Choose One</md-option>
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