    /**
     * @class Ext.form.field.Number
     * @extends Ext.form.field.Spinner

    A numeric text field that provides automatic keystroke filtering to disallow non-numeric characters,
    and numeric validation to limit the value to a range of valid numbers. The range of acceptable number
    values can be controlled by setting the {@link #minValue} and {@link #maxValue} configs, and fractional
    decimals can be disallowed by setting {@link #allowDecimals} to `false`.

    By default, the number field is also rendered with a set of up/down spinner buttons and has
    up/down arrow key and mouse wheel event listeners attached for incrementing/decrementing the value by the
    {@link #step} value. To hide the spinner buttons set `{@link #hideTrigger hideTrigger}:true`; to disable the arrow key
    and mouse wheel handlers set `{@link #keyNavEnabled keyNavEnabled}:false` and
    `{@link #mouseWheelEnabled mouseWheelEnabled}:false`. See the example below.

    #Example usage:#
    {@img Ext.form.Number/Ext.form.Number1.png Ext.form.Number component}
        Ext.create('Ext.form.Panel', {
            title: 'On The Wall',
            width: 300,
            bodyPadding: 10,
            renderTo: Ext.getBody(),
            items: [{
                xtype: 'numberfield',
                anchor: '100%',
                name: 'bottles',
                fieldLabel: 'Bottles of Beer',
                value: 99,
                maxValue: 99,
                minValue: 0
            }],
            buttons: [{
                text: 'Take one down, pass it around',
                handler: function() {
                    this.up('form').down('[name=bottles]').spinDown();
                }
            }]
        });

    #Removing UI Enhancements#
    {@img Ext.form.Number/Ext.form.Number2.png Ext.form.Number component}
        Ext.create('Ext.form.Panel', {
            title: 'Personal Info',
            width: 300,
            bodyPadding: 10,
            renderTo: Ext.getBody(),
            items: [{
                xtype: 'numberfield',
                anchor: '100%',
                name: 'age',
                fieldLabel: 'Age',
                minValue: 0, //prevents negative numbers

                // Remove spinner buttons, and arrow key and mouse wheel listeners
                hideTrigger: true,
                keyNavEnabled: false,
                mouseWheelEnabled: false
            }]
        });

    #Using Step#
        Ext.create('Ext.form.Panel', {
            renderTo: Ext.getBody(),
            title: 'Step',
            width: 300,
            bodyPadding: 10,
            items: [{
                xtype: 'numberfield',
                anchor: '100%',
                name: 'evens',
                fieldLabel: 'Even Numbers',

                // Set step so it skips every other number
                step: 2,
                value: 0,

                // Add change handler to force user-entered numbers to evens
                listeners: {
                    change: function(field, value) {
                        value = parseInt(value, 10);
                        field.setValue(value + value % 2);
                    }
                }
            }]
        });

     * @constructor
     * Creates a new Number field
     * @param {Object} config Configuration options
     *
     * @xtype numberfield
     * @markdown
     * @docauthor Jason Johnston <jason@sencha.com>
     */
    Ext.define('Ext.form.field.Number', {
        extend:'Ext.form.field.Spinner',
        alias: 'widget.numberfield',
        alternateClassName: ['Ext.form.NumberField', 'Ext.form.Number'],

        /**
         * @cfg {RegExp} stripCharsRe @hide
         */
        /**
         * @cfg {RegExp} maskRe @hide
         */

        /**
         * @cfg {Boolean} allowDecimals False to disallow decimal values (defaults to true)
         */
        allowDecimals : true,

        /**
         * @cfg {String} decimalSeparator Character(s) to allow as the decimal separator (defaults to '.')
         */
        decimalSeparator : '.',

        /**
         * @cfg {Number} decimalPrecision The maximum precision to display after the decimal separator (defaults to 2)
         */
        decimalPrecision : 2,

        /**
         * @cfg {Number} minValue The minimum allowed value (defaults to Number.NEGATIVE_INFINITY). Will be used by
         * the field's validation logic, and for
         * {@link Ext.form.field.Spinner#setSpinUpEnabled enabling/disabling the down spinner button}.
         */
        minValue: Number.NEGATIVE_INFINITY,

        /**
         * @cfg {Number} maxValue The maximum allowed value (defaults to Number.MAX_VALUE). Will be used by
         * the field's validation logic, and for
         * {@link Ext.form.field.Spinner#setSpinUpEnabled enabling/disabling the up spinner button}.
         */
        maxValue: Number.MAX_VALUE,

        /**
         * @cfg {Number} step Specifies a numeric interval by which the field's value will be incremented or
         * decremented when the user invokes the spinner. Defaults to <tt>1</tt>.
         */
        step: 1,

        /**
         * @cfg {String} minText Error text to display if the minimum value validation fails (defaults to 'The minimum
         * value for this field is {minValue}')
         */
        minText : 'The minimum value for this field is {0}',

        /**
         * @cfg {String} maxText Error text to display if the maximum value validation fails (defaults to 'The maximum
         * value for this field is {maxValue}')
         */
        maxText : 'The maximum value for this field is {0}',

        /**
         * @cfg {String} nanText Error text to display if the value is not a valid number.  For example, this can happen
         * if a valid character like '.' or '-' is left in the field with no number (defaults to '{value} is not a valid number')
         */
        nanText : '{0} is not a valid number',

        /**
         * @cfg {String} negativeText Error text to display if the value is negative and {@link #minValue} is set to
         * <tt>0</tt>. This is used instead of the {@link #minText} in that circumstance only.
         */
        negativeText : 'The value cannot be negative',

        /**
         * @cfg {String} baseChars The base set of characters to evaluate as valid numbers (defaults to '0123456789').
         */
        baseChars : '0123456789',

        /**
         * @cfg {Boolean} autoStripChars True to automatically strip not allowed characters from the field. Defaults to <tt>false</tt>
         */
        autoStripChars: false,

        initComponent: function() {
            var me = this,
                allowed;

            this.callParent();

            me.setMinValue(me.minValue);
            me.setMaxValue(me.maxValue);

            // Build regexes for masking and stripping based on the configured options
            allowed = me.baseChars + '';
            if (me.allowDecimals) {
                allowed += me.decimalSeparator;
            }
            if (me.minValue < 0) {
                allowed += '-';
            }
            allowed = Ext.String.escapeRegex(allowed);
            me.maskRe = new RegExp('[' + allowed + ']');
            if (me.autoStripChars) {
                me.stripCharsRe = new RegExp('[^' + allowed + ']', 'gi');
            }
        },

        /**
         * Runs all of Number's validations and returns an array of any errors. Note that this first
         * runs Text's validations, so the returned array is an amalgamation of all field errors.
         * The additional validations run test that the value is a number, and that it is within the
         * configured min and max values.
         * @param {Mixed} value The value to get errors for (defaults to the current field value)
         * @return {Array} All validation errors for this field
         */
        getErrors: function(value) {
            var me = this,
                errors = me.callParent(arguments),
                format = Ext.String.format,
                num;

            value = Ext.isDefined(value) ? value : this.processRawValue(this.getRawValue());

            if (value.length < 1) { // if it's blank and textfield didn't flag it then it's valid
                 return errors;
            }

            value = String(value).replace(me.decimalSeparator, '.');

            if(isNaN(value)){
                errors.push(format(me.nanText, value));
            }

            num = me.parseValue(value);

            if (me.minValue === 0 && num < 0) {
                errors.push(this.negativeText);
            }
            else if (num < me.minValue) {
                errors.push(format(me.minText, me.minValue));
            }

            if (num > me.maxValue) {
                errors.push(format(me.maxText, me.maxValue));
            }

            return errors;
        },

        rawToValue: function(rawValue) {
            return this.fixPrecision(this.parseValue(rawValue)) || rawValue || null;
        },

        valueToRaw: function(value) {
            var me = this,
                decimalSeparator = me.decimalSeparator;
            value = me.parseValue(value);
            value = me.fixPrecision(value);
            value = Ext.isNumber(value) ? value : parseFloat(String(value).replace(decimalSeparator, '.'));
            value = isNaN(value) ? '' : String(value).replace('.', decimalSeparator);
            return value;
        },

        onChange: function() {
            var me = this,
                value = me.getValue(),
                valueIsNull = value === null;

            me.callParent(arguments);

            // Update the spinner buttons
            me.setSpinUpEnabled(valueIsNull || value < me.maxValue);
            me.setSpinDownEnabled(valueIsNull || value > me.minValue);
        },

        /**
         * Replaces any existing {@link #minValue} with the new value.
         * @param {Number} value The minimum value
         */
        setMinValue : function(value) {
            this.minValue = Ext.Number.from(value, Number.NEGATIVE_INFINITY);
        },

        /**
         * Replaces any existing {@link #maxValue} with the new value.
         * @param {Number} value The maximum value
         */
        setMaxValue: function(value) {
            this.maxValue = Ext.Number.from(value, Number.MAX_VALUE);
        },

        // private
        parseValue : function(value) {
            value = parseFloat(String(value).replace(this.decimalSeparator, '.'));
            return isNaN(value) ? null : value;
        },

        /**
         * @private
         *
         */
        fixPrecision : function(value) {
            var me = this,
                nan = isNaN(value),
                precision = me.decimalPrecision;

            if (nan || !value) {
                return nan ? '' : value;
            } else if (!me.allowDecimals || precision <= 0) {
                precision = 0;
            }

            return parseFloat(Ext.Number.toFixed(parseFloat(value), precision));
        },

        beforeBlur : function() {
            var me = this,
                v = me.parseValue(me.getRawValue());

            if (!Ext.isEmpty(v)) {
                me.setValue(v);
            }
        },

        onSpinUp: function() {
            var me = this;
            if (!me.readOnly) {
                me.setValue(Ext.Number.constrain(me.getValue() + me.step, me.minValue, me.maxValue));
            }
        },

        onSpinDown: function() {
            var me = this;
            if (!me.readOnly) {
                me.setValue(Ext.Number.constrain(me.getValue() - me.step, me.minValue, me.maxValue));
            }
        }
    });