带复选框且支持搜索功能的下拉列表6

// private
    onLoad : function()
    {
        if (!this.hasFocus)
        {
            return;
        }
        if (this.store.getCount() > 0)
        {
            this.expand();
            this.restrictHeight();
            if (this.lastQuery == this.allQuery)
            {
                if (this.editable)
                {
                    this.el.dom.select();
                }
                if (!this.selectByValue(this.value, true))
                {
                    this.select(0, true);
                }
            }
            else
            {
                this.selectNext();
                if (this.typeAhead && this.lastKey != Ext.EventObject.BACKSPACE && this.lastKey != Ext.EventObject
                        .DELETE)
                {
                    this.taTask.delay(this.typeAheadDelay);
                }
            }
        }
        else
        {
            this.onEmptyResults();
        }
    },

    // private
    onTypeAhead : function()
    {
        
        if (this.store.getCount() > 0)
        {
            var r = this.store.getAt(0);
            var newValue = r.data[this.displayField];
            var len = newValue.length;
            var selStart = this.getRawValue().length;
            if (selStart != len)
            {
                this.setRawValue(newValue);
                this.selectText(selStart, newValue.length);
            }
        }
    },