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KnockoutJS lost viewmodel

I am having problems with the proof of concept. What I am trying to do is open a jQuery dialog on button click. The content of the dialog is bound to the viewmodel and the dialog calls the json service to fetch some data to populate that model.

Doing two problems with the code I have:

  • vmAccount viewmodel will only bind if the div is visible from the initial page load.
  • vmAccount viewmodel is undefined in SearchForCustomerAccounts or DisplayResults, even though it is a global var for those

$(function() {

  var vmAccount = function() {
    var self = this;
    this.Accounts = ko.observableArray();
    this.Name = ko.observable('Jimmy');
  };

  function DisplayDialog() {

    $("#Dialog").dialog({
      resizable: false,
      height: 140,
      modal: true,
      buttons: {
        "Search": function() {
          SearchForCustomerAccounts();

        },
        Cancel: function() {
          $(this).dialog("close");
        }
      }
    });
  }

  function SearchForCustomerAccounts() {
    console.log("Name: " + vmAccount.Name);
    $.ajax({
      url: "api/CustomerSearchController/" + vmAccount.Name,
      type: "GET",
      dataType: "json",
      success: function(data) {
        DisplayResults(data);
      }
    });
  }

  function DisplayResults(data) {
    vmAccount.Accounts.removeAll();
    for (var i = 0; i < data.length; i++) {
      vmAccount.Accounts.push(data[i]);
    }
  };

  $("#butSearch").button().on("click", function() {
    DisplayDialog();
  });

  $(document).ready(function() {
    ko.applyBindings(vmAccount);
  });
});
      

        
        
        
      

    
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/knockout/3.1.0/knockout-min.js"></script>
<script src="https://code.jquery.com/ui/1.11.4/jquery-ui.js"></script>

<body>
  <button id="butSearch">Open</button>

  <div id="Dialog" style="visibility: visible">
    <form id="Account">
      <p>Customer Name</p>
      <input type="text" data-bind="value: Name" />
    </form>
  </div>

</body>
Run code


I'm new to javascript and knockout so its probably something simple missing. Appreciate any help you guys can provide, thanks!

+3


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3 answers


1) Yours vmAccount

is a function, but you are trying to use it as an instance.

2) To get a value from the observed KO, you have to name it (reversal). So use vmAccount.Name()

instead vmAccount.Name

.



$(function() {

  function VmAccount () {
    var self = this;
    this.Accounts = ko.observableArray();
    this.Name = ko.observable('Jimmy');
  };
  
  var vmAccount = new VmAccount();

  function DisplayDialog() {

    $("#Dialog").dialog({
      resizable: false,
      height: 140,
      modal: true,
      buttons: {
        "Search": function() {
          SearchForCustomerAccounts();

        },
        Cancel: function() {
          $(this).dialog("close");
        }
      }
    });
  }

  function SearchForCustomerAccounts() {
    console.log("Name: " + vmAccount.Name());
    $.ajax({
      url: "api/CustomerSearchController/" + vmAccount.Name(),
      type: "GET",
      dataType: "json",
      success: function(data) {
        DisplayResults(data);
      }
    });
  }

  function DisplayResults(data) {
    vmAccount.Accounts.removeAll();
    for (var i = 0; i < data.length; i++) {
      vmAccount.Accounts.push(data[i]);
    }
  };

  $("#butSearch").button().on("click", function() {
    DisplayDialog();
  });

  $(document).ready(function() {
    ko.applyBindings(vmAccount);
  });
});
      

        
        
        
      

    
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/knockout/3.1.0/knockout-min.js"></script>
<script src="https://code.jquery.com/ui/1.11.4/jquery-ui.js"></script>

<body>
  <button id="butSearch">Open</button>

  <div id="Dialog" style="visibility: visible">
    <form id="Account">
      <p>Customer Name</p>
      <input type="text" data-bind="value: Name" />
    </form>
  </div>

</body>
Run code


+1


source


The code should look like this: vmAccount is empty because the function returns nothing;

var vmAccount = function() {
var self = this;
this.Accounts = ko.observableArray();
this.Name = ko.observable('Jimmy');
return this;


};

+1


source 


$(function() {

  var vmAccount = {
    Accounts : ko.observableArray(),
    Name : ko.observable('Jimmy'),
  };

  function DisplayDialog() {

    $("#Dialog").dialog({
      resizable: false,
      height: 140,
      modal: true,
      buttons: {
        "Search": function() {
          SearchForCustomerAccounts();

        },
        Cancel: function() {
          $(this).dialog("close");
        }
      }
    });
  }

  function SearchForCustomerAccounts() {
    console.log("Name: " + vmAccount.Name());
    $.ajax({
      url: "api/CustomerSearchController/" + vmAccount.Name(),
      type: "GET",
      dataType: "json",
      success: function(data) {
        DisplayResults(data);
      }
    });
  }

  function DisplayResults(data) {
    vmAccount.Accounts.removeAll();
    for (var i = 0; i < data.length; i++) {
      vmAccount.Accounts.push(data[i]);
    }
  };

  $("#butSearch").button().on("click", function() {
    DisplayDialog();
  });

  $(document).ready(function() {
    ko.applyBindings(vmAccount);
  });
});
      

        
        
        
      

    
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/knockout/3.1.0/knockout-min.js"></script>
<script src="https://code.jquery.com/ui/1.11.4/jquery-ui.js"></script>

<body>
  <button id="butSearch">Open</button>

  <div id="Dialog" style="visibility: visible">
    <form id="Account">
      <p>Customer Name</p>
      <input type="text" data-bind="value: Name()" />
    </form>
  </div>

</body>
Run code


0


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