在jQuery对话框中敲除'with'binding和select2

Question

问题:

当在嵌套在使用knockout with数据绑定的元素下的jQuery对话框上使用时,select2 jQuery插件不起作用.删除with绑定,select2工作正常.如果with绑定到嵌套属性,则它将停止工作.

背景:

因此,我必须在3小时内努力争取让select2在jQuery对话框表单上工作....讨论关于这个谚语错误树的问题,我认为它纯粹是jQuery对话框和select2.它可能从一开始就_allowInteraction修复了.直到我把问题直接解决为简单的步骤,并且因为开始显露自己.问题在于with绑定.

放弃

当我为阻止jsFiddle的asinine公司工作时道歉.此外,由于实际模型非常大,我为了说明目的而细分了我的实现.

// models

function Department() {
  this.name         = ko.observable('dept1');
  this.selectedTeam = ko.observable( new Team() );
}
    
function Team() {
  this.name = ko.observable('team1');
}
    
function MainModel() {
  this.department = new Department();
  this.showTeam   = function() { 
    $('#addTeamDialog').dialog('open');
  };
}

// setup

ko.applyBindings( new MainModel() );
    	
$('#addTeamDialog').dialog({
  // fix allow select2 to work on the jq dialog
  _allowInteraction: function (event) {
    return !!$(event.target).is(".select2-input") || this._super(event);
  }		
});
    	
$('#someList').select2({
  data: [
    { id: 0, text: 'enhancement' },
    { id: 1, text: 'bug' },
    { id: 2, text: 'duplicate' },
    { id: 3, text: 'invalid' },
    { id: 4, text: 'wontfix' }
  ]
});

<link href="http://code.jquery.com/ui/1.11.4/themes/ui-lightness/jquery-ui.css" rel="stylesheet"/>
<link href="//cdnjs.cloudflare.com/ajax/libs/select2/4.0.0/css/select2.min.css" rel="stylesheet" />

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="http://code.jquery.com/ui/1.11.4/jquery-ui.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/knockout/3.2.0/knockout-min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/select2/4.0.0/js/select2.full.min.js"></script>

<button data-bind="click: showTeam">Add Team</button>

<div id="addTeamDialog">
  <fieldset data-bind="with: department">
    
    <div class="lite-dialog-field">
      <div class="label">
        <span data-bind="text: name"></span>
      </div>
      <div class="field">
        <input type="hidden" id="someList" />
      </div>    
    </div>
        
  </fieldset>
</div>

删除data-bindon fieldset和select2工作正常.

当data-bindon上fieldset设置为departmentselect2工作正常.

当data-bindon fieldset设置为department.selectedTeamselect2不起作用时.

Answer 1

当您使用 Knockout 时，强烈建议将外部库（例如 select2）包装在绑定中。虽然您只初始化它们一次，但诸如with、template或 之类的绑定foreach可以在此后随时修改 DOM。

您面临以下任一危险

1. 当 Knockout 尚未呈现任何内容时过早初始化 select2，或者
2. 淘汰赛丢弃并在稍后重新渲染标记，以便您的 select2 突然不再绑定

例如，当Department.selectedTeam发生变化时就会发生这种情况。

我从 Knockouts 的rniemeyer 本人那里找到了一个快速而肮脏的 select2 绑定。除此之外，为了一致性和安全性，我只是将 select2 标记更改为标准<select>，并使其成为适当的可观察值。MainModel.department

ko.bindingHandlers.select2 = {
    init: function(element, valueAccessor) {
      var options = ko.toJS(valueAccessor()) || {};
      setTimeout(function() { 
          $(element).select2(options);
      }, 0);
    }
};

// models

function Department() {
  this.name         = ko.observable('dept1');
  this.selectedTeam = ko.observable( new Team() );
};
    
function Team() {
  this.name     = ko.observable('team1');
  this.values   = ["red", "grey", "blue"];
  this.selected = ko.observableArray(["blue"]);
};
    
function MainModel() {
  this.department = ko.observable( new Department() );
  this.showTeam   = function() { 
    $('#addTeamDialog').dialog('open');
  };
};

// setup

ko.applyBindings( new MainModel() );
    	
$('#addTeamDialog').dialog({
  // fix allow select2 to work on the jq dialog
  _allowInteraction: function (event) {
    return !!$(event.target).is(".select2-input") || this._super(event);
  }		
});

select {
  width: 200px;
}

<link href="http://code.jquery.com/ui/1.11.4/themes/ui-lightness/jquery-ui.css" rel="stylesheet"/>
<link href="//cdnjs.cloudflare.com/ajax/libs/select2/4.0.0/css/select2.min.css" rel="stylesheet" />
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="http://code.jquery.com/ui/1.11.4/jquery-ui.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/knockout/3.2.0/knockout-min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/select2/4.0.0/js/select2.full.min.js"></script>

<button data-bind="click: showTeam">Add Team</button>

<div id="addTeamDialog">
  <fieldset data-bind="with: department().selectedTeam">
    
    <select data-bind="options: values,
                       selectedOptions: selected, 
                       select2: { placeholder: 'pick some colors' }">
    </select>
        
  </fieldset>
</div>