First you need a combobox that will also allow you to clear your filter. So you will need a second button on the combobox which allows you to clear if a filter is active. For that you don't need to do much because the framework already cover such a feature, even if it is not documented.
Here's a older version but it should still work on 4.2
Ext.define('Ext.ux.form.field.FilterCombo', {
extend: 'Ext.form.field.ComboBox',
alias: 'widget.filtercombo',
/**
* @cfg {string} recordField
* @required
* The fieldname of the record that contains the filtervalue
*/
/**
* @cfg {string} searchField
* @required
* The fieldname on which the filter should be applied
*/
/**
* @cfg {boolean} clearable
* Indicates if the clear trigger should be hidden. Defaults to <tt>true</tt>.
*/
clearable: true,
initComponent: function () {
var me = this;
// never submit it
me.submitValue = false;
if (me.clearable)
me.trigger2Cls = 'x-form-clear-trigger';
else
delete me.onTrigger2Click;
me.addEvents(
/**
* @event clear
*
* @param {Ext.ux.form.field.FilterCombo} FilterCombo The filtercombo that triggered the event
*/
'clear',
/**
* @event beforefilter
*
* @param {Ext.ux.form.field.FilterCombo} FilterCombo The filtercombo that triggered the event
* @param {String/Number/Boolean/Float/Date} value The value to filter by
* @param {string} field The field to filter on
*/
'beforefilter'
);
me.callParent(arguments);
// fetch the id the save way
var ident = me.getId();
me.on('select', function (me, rec) {
var value = rec[0].data[me.recordField],
field = me.searchField;
me.fireEvent('beforefilter', me, value, field)
me.onShowClearTrigger(true);
me.onSearch(value, field);
}, me);
me.on('afterrender', function () { me.onShowClearTrigger(); }, me);
},
/**
* @abstract onSearch
* running a search on the store that may be removed separately
* @param {String/Number/Boolean/Float/Date} val The value to search for
* @param {String} field The name of the Field to search on
*/
onSearch: Ext.emptyFn,
/**
* @abstract onFilterRemove
* removing filters from the the
* @param {Boolean} silent Identifies if the filter should be removed without reloading the store
*/
onClear: Ext.emptyFn,
onShowClearTrigger: function (show) {
var me = this;
if (!me.clearable)
return;
show = (Ext.isBoolean(show)) ? show : false;
if (show) {
me.triggerEl.each(function (el, c, i) {
if (i === 1) {
el.setWidth(el.originWidth, false);
el.setVisible(true);
me.active = true;
}
});
} else {
me.triggerEl.each(function (el, c, i) {
if (i === 1) {
el.originWidth = el.getWidth();
el.setWidth(0, false);
el.setVisible(false);
me.active = false;
}
});
}
// Version specific methods
if (Ext.lastRegisteredVersion.shortVersion > 407) {
me.updateLayout();
} else {
me.updateEditState();
}
},
/**
* @override onTrigger2Click
* eventhandler
*/
onTrigger2Click: function (args) {
this.clear();
},
/**
* @private clear
* clears the current search
*/
clear: function () {
var me = this;
if (!me.clearable)
return;
me.onClear(false);
me.clearValue();
me.onShowClearTrigger(false);
me.fireEvent('clear', me);
}
});
Now that you have a combo that fires events for filter and clear you need to implement it. For that you need to know that not the grid filters or execute the loading, it is the store. Per default a store is configured with
remoteSort: false,
remoteFilter: false,
remoteGroup: false
So here is a example implementation
{
xtype: 'filtercombo',
id: 'iccombo',
store: Ext.StoreMgr.lookup('Combostore'),
fieldLabel: 'Short State',
displayField: 'States',
valueField: 'States',
typeAhead: true,
triggerAction: 'all',
queryMode: 'remote',
name: 'State',
labelWidth: 125,
anchor: '95%',
recordField: 'ComboStoreFieldName',
searchField: 'GridStoreFieldName',
clearable: false,
onSearch: function (me, value, field) {
// You many also use component query to access your grid and call getStore()
var store = Ext.StoreMgr.lookup('YourStoreIdName');
// Clear existing filters
if (store.isFiltered()) {
store.clearFilter(false);
}
// Build filter
// Apply filter to store
store.filter(field,value);
}
}
