Javascript – Load default value for a comboBox extjs

comboboxextjsjavascriptstore

how can i load a default value from my json store (remote) into a combobox ,
i've tried load the store before render the combo , and use setValue()
i want my combo to display the first result in the store
plz tell me the right way to do this and thanx

Best Answer

You need to set the value property to the value of the first element after the store is loaded

Ext.ns('MyNamespace');

MyNamespace.MyComboBox = Ext.extend(Ext.form.ComboBox, {
  displayField: 'displayValue',
  triggerAction: 'all',
  valueField: 'ID',

  initComponent: function () {
    this.store = new Ext.data.JsonStore({
      url: 'url',
      baseParams: {
        //params
      },
      fields: [
        {name:'ID', mapping: 'ID', type: 'int'},
        {name:'displayValue', mapping: 'displayValue', type: 'string'},
      ],
      root: 'root'
    });

    var me = this;
    this.store.on('load',function(store) {
      me.setValue(store.getAt(0).get('ID'));
    })

    MyNamespace.MyComboBox.superclass.initComponent.call(this);

    this.store.load();
  }

});

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