unique form field validation in extjs4 - forms

Question

Is there a cleaner way to define unique form field in extjs. Below is a sample code that is checking on client UID on client creation/edition. This code is working but has some bugs - for example on client creation if you enter a value that is already present in DB validator returns true until you unfocus the field.
Ext.define('AM.view.client.UniqueField', {
extend: 'Ext.form.field.Text',
alias : 'widget.uniquefield',
vtype: 'UniqueUid',
initComponent: function() {
Ext.apply(Ext.form.field.VTypes, {
UniqueUidMask : /[0-9]/i,
UniqueUid : function(val,field) {
if (val.length < 9) {
Ext.apply(Ext.form.field.VTypes, {
UniqueUidText: 'Company ID is too small'
});
return false;
} else {
var paste=/^[0-9_]+$/;
if (!paste.test(val)) {
Ext.apply(Ext.form.field.VTypes, {
UniqueUidText: 'Ivalid characters'
});
return false;
} else {
var mask = new Ext.LoadMask(field.up('form'),{msg:'Please wait checking....'});
mask.show();
var test= 0;
var store = Ext.create('AM.store.Clients');
store.load({params:{'uid':val, 'id': Ext.getCmp('client_id').getValue()}});
store.on('load', function(test) {
mask.hide();
if(parseInt(store.getTotalCount())==0){
this.uniqueStore(true);
}else{
Ext.apply(Ext.form.field.VTypes, {
UniqueUidText: 'Company ID is already present'
});
this.uniqueStore(false);
}
},this)
return true;
}
}}
},this);
this.callParent(arguments);
},
uniqueStore: function(is_error){
Ext.apply(Ext.form.field.VTypes, {
UniqueUidMask : /[0-9]/i,
UniqueUid : function(val,field) {
if (val.length < 9) {
Ext.apply(Ext.form.field.VTypes, {
UniqueUidText: 'Company ID is too small'
});
return false;
} else {
var paste=/^[0-9_]+$/;
if (!paste.test(val)) {
Ext.apply(Ext.form.field.VTypes, {
UniqueUidText: 'Ivalid characters'
});
return false;
} else {
var mask = new Ext.LoadMask(field.up('form'),{msg:'Please wait checking....'});
mask.show();
var store = Ext.create('AM.store.Clients');
store.load({params:{'uid':val, 'id': Ext.getCmp('client_id').getValue()}});
store.on('load', function(test) {
mask.hide();
if(parseInt(store.getTotalCount())==0){
this.uniqueStore(true);
}else{
this.uniqueStore(false);
}
},this)
return is_error;
}
}}
},this);
}
});

Answer 1

How about using server side validation?
I answered to similar issue here: extjs4 rails 3 model validation for uniqueness
Obviously you can change it to use "ajax" instead of "rest" proxy.