Ext JS 4 Remote To Local Hybrid ComboBox Plugin

RemoteToLocalComboBox.js

/**
	This combo functions as a remote-local ExtJS combo hybrid.  It starts out
	as a remote combo so that nothing is loaded until the trigger button is clicked
	or the user starts typing in the combobox.  Once the data is loaded, it switches
	to local mode so that no more queries are made to the server.  It therefore
	assumes that all data is loaded on the first load request. It also shows the
	loading UI when data is being loaded since it starts out as 'remote'.
*/
Ext.define("Ext.ux.form.field.RemoteToLocalComboBox", {
	extend: 'Ext.AbstractPlugin',
	alias: 'plugin.remotetolocalcombo',

	init: function(combo) {
		this.combo = combo;
		combo.queryMode = 'remote';
		this.callParent();

		combo.getStore().on('load', this.onComboStoreLoad, this);
	},

	onComboStoreLoad : function () {
		Ext.apply(this.combo, {queryMode: 'local'});
	}
});

why not just use: queryCaching:true ??
http://docs.sencha.com/ext-js/4-2/#!/api/Ext.form.field.ComboBox-cfg-queryCaching

Works a little differently. See comments at http://ahlearns.wordpress.com/2012/09/06/ext-js-4-a-remote-to-local-querymode-hybrid-combobox/

This is an awesome solution to a common need. Works on 4.2.2, too.

I think it's useful to set combo.minChars = 0 on init() because the default for queryMode remote is 4 chars instead of the default of 0 for local.

Also, I would change line 18 to combo.mon(combo.getStore(), ...
So when the combo is destroyed the listener is, too.