我有一个 ExtJS 组合框，要求有一个附加值，用户可以从第一个值中选择所有选项，如下所示：
Ext.onReady(function () {
// The data store containing the list of states
var states = Ext.create('Ext.data.Store', {
fields: ['abbreviation', 'name'],
data: [{
name: 'Select all',
abbreviation: 'ALL'
},
{
name: 'ALABAMA',
abbreviation: 'AL'
}, {
name: 'ALASKA',
abbreviation: 'AK'
}, {
name: 'AMERICAN SAMOA',
abbreviation: 'AS'
}, {
name: 'ARIZONA',
abbreviation: 'AZ'
}, {
name: 'ARKANSAS',
abbreviation: 'AR'
}, {
name: 'CALIFORNIA',
abbreviation: 'CA'
}, {
name: 'COLORADO',
abbreviation: 'CO'
}, {
name: 'CONNECTICUT',
abbreviation: 'CT'
}, {
name: 'DELAWARE',
abbreviation: 'DE'
}, {
name: 'DISTRICT OF COLUMBIA',
abbreviation: 'DC'
}, {
name: 'FEDERATED STATES OF MICRONESIA',
abbreviation: 'FM'
}, {
name: 'FLORIDA',
abbreviation: 'FL'
}, {
name: 'GEORGIA',
abbreviation: 'GA'
}, {
name: 'GUAM',
abbreviation: 'GU'
}, {
name: 'HAWAII',
abbreviation: 'HI'
}, {
name: 'IDAHO',
abbreviation: 'ID'
}, {
name: 'ILLINOIS',
abbreviation: 'IL'
}, {
name: 'INDIANA',
abbreviation: 'IN'
}, {
name: 'IOWA',
abbreviation: 'IA'
}, {
name: 'KANSAS',
abbreviation: 'KS'
}, {
name: 'KENTUCKY',
abbreviation: 'KY'
}, {
name: 'LOUISIANA',
abbreviation: 'LA'
}, {
name: 'MAINE',
abbreviation: 'ME'
}, {
name: 'MARSHALL ISLANDS',
abbreviation: 'MH'
}, {
name: 'MARYLAND',
abbreviation: 'MD'
}, {
name: 'MASSACHUSETTS',
abbreviation: 'MA'
}, {
name: 'MICHIGAN',
abbreviation: 'MI'
}, {
name: 'MINNESOTA',
abbreviation: 'MN'
}, {
name: 'MISSISSIPPI',
abbreviation: 'MS'
}, {
name: 'MISSOURI',
abbreviation: 'MO'
}, {
name: 'MONTANA',
abbreviation: 'MT'
}, {
name: 'NEBRASKA',
abbreviation: 'NE'
}, {
name: 'NEVADA',
abbreviation: 'NV'
}, {
name: 'NEW HAMPSHIRE',
abbreviation: 'NH'
}, {
name: 'NEW JERSEY',
abbreviation: 'NJ'
}, {
name: 'NEW MEXICO',
abbreviation: 'NM'
}, {
name: 'NEW YORK',
abbreviation: 'NY'
}, {
name: 'NORTH CAROLINA',
abbreviation: 'NC'
}, {
name: 'NORTH DAKOTA',
abbreviation: 'ND'
}, {
name: 'NORTHERN MARIANA ISLANDS',
abbreviation: 'MP'
}, {
name: 'OHIO',
abbreviation: 'OH'
}, {
name: 'OKLAHOMA',
abbreviation: 'OK'
}, {
name: 'OREGON',
abbreviation: 'OR'
}, {
name: 'PALAU',
abbreviation: 'PW'
}, {
name: 'PENNSYLVANIA',
abbreviation: 'PA'
}, {
name: 'PUERTO RICO',
abbreviation: 'PR'
}, {
name: 'RHODE ISLAND',
abbreviation: 'RI'
}, {
name: 'SOUTH CAROLINA',
abbreviation: 'SC'
}, {
name: 'SOUTH DAKOTA',
abbreviation: 'SD'
}, {
name: 'TENNESSEE',
abbreviation: 'TN'
}, {
name: 'TEXAS',
abbreviation: 'TX'
}, {
name: 'UTAH',
abbreviation: 'UT'
}, {
name: 'VERMONT',
abbreviation: 'VT'
}, {
name: 'VIRGIN ISLANDS',
abbreviation: 'VI'
}, {
name: 'VIRGINIA',
abbreviation: 'VA'
}, {
name: 'WASHINGTON',
abbreviation: 'WA'
}, {
name: 'WEST VIRGINIA',
abbreviation: 'WV'
}, {
name: 'WISCONSIN',
abbreviation: 'WI'
}, {
name: 'WYOMING',
abbreviation: 'WY'
}]
});
Ext.define('comboSelectedCount', {
alias: 'plugin.selectedCount',
init: function (combo) {
var fl = combo.getFieldLabel();
combo.on({
select: function (me, records) {
var len = records.length,
store = combo.getStore();
// toggle all selections
Ext.each(records, function (obj, i, recordsItself) {
if (records[i].data.abbreviation === 'ALL') {
len = store.getCount();
combo.select(store.getRange());
}
});
me.setFieldLabel(fl + ' (' + len + ' selected)');
},
beforedeselect: function (me, record, index) {
me.setFieldLabel(fl);
}
})
}
});
// Create the combo box, attached to the states data store
Ext.create('Ext.form.ComboBox', {
disabled: false,
plugins: ['selectedCount'],
fieldLabel: 'Choose State',
labelAlign: 'top',
store: states,
queryMode: 'local',
editable: false,
displayField: 'name',
valueField: 'abbreviation',
renderTo: Ext.getBody(),
multiSelect: true,
maxSelections: 3,
width: 400,
displayTpl: '<tpl for=".">' +
'{name}' +
'<tpl if="xindex < xcount">, </tpl>' +
'</tpl>',
listConfig: {
itemTpl: '{name} <div class="chkbox"></div>'
},
listeners: {
}
});
});
当用户取消选中“全选”或选择“全选”以外的任何其他项目时，我希望能够取消全选。
真的不知道该怎么做？
JSFiddle在这里：http: //jsfiddle.net/dFEsc/1/