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JavaScript [ExtJs3]: Avoid default filtering in ComboBox

We had a requirement where we wanted to avoid default filtering provided by the ExtJs ComboBox. Instead we wanted to control it based on our business rules. To avoid default filtering we added “editable:false”, but it didn’t help much. As after selecting any value user cannot clear the value from field. We tried few more permutation-combination to achieve all the behaviour we wanted, but nothing worked.

 

Use-Cases we wanted to achieve in combo box

  • Force user to select value from drop down list
  • User can clear the value
  • Disable the default filtering as filtering is applied based on some business rule and default filtering was clearing it

 

Here is the final outcome, which satisfied all the use-cases.

 

var combo = new Ext.form.ComboBox({
            store        : store,
            displayField : displayField,
            mode         : 'local',
            triggerAction: 'all',
            forceSelection: true,
            autoSelect: false,
            // don't allow user to enter the value
            // But at the same time he should be able to delete the value
            // overriding the function to avoid default filter clearing
            initQuery:  function(){
                this.doQuery('');
                this.setValue('');
            }
});

 

PS: Extjs version – 3.4









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