    /**
     * @class Ext.util.Floating
     * A mixin to add floating capability to a Component
     */
    Ext.define('Ext.util.Floating', {

        uses: ['Ext.Layer', 'Ext.window.Window'],

        /**
         * @cfg {Boolean} focusOnToFront
         * Specifies whether the floated component should be automatically {@link #focus focused} when it is
         * {@link #toFront brought to the front}. Defaults to true.
         */
        focusOnToFront: true,

        /**
         * @cfg {String/Boolean} shadow Specifies whether the floating component should be given a shadow. Set to
         * <tt>true</tt> to automatically create an {@link Ext.Shadow}, or a string indicating the
         * shadow's display {@link Ext.Shadow#mode}. Set to <tt>false</tt> to disable the shadow.
         * (Defaults to <tt>'sides'</tt>.)
         */
        shadow: 'sides',

        constructor: function(config) {
            this.floating = true;
            this.el = Ext.create('Ext.Layer', Ext.apply({}, config, {
                hideMode: this.hideMode,
                hidden: this.hidden,
                shadow: Ext.isDefined(this.shadow) ? this.shadow : 'sides',
                shadowOffset: this.shadowOffset,
                constrain: false,
                shim: this.shim === false ? false : undefined
            }), this.el);
        },

        onFloatRender: function() {
            var me = this;
            me.zIndexParent = me.getZIndexParent();
            me.setFloatParent(me.ownerCt);
            delete me.ownerCt;

            if (me.zIndexParent) {
                me.zIndexParent.registerFloatingItem(me);
            } else {
                Ext.WindowManager.register(me);
            }
        },

        setFloatParent: function(floatParent) {
            var me = this;

            // Remove listeners from previous floatParent
            if (me.floatParent) {
                me.mun(me.floatParent, {
                    hide: me.onFloatParentHide,
                    show: me.onFloatParentShow,
                    scope: me
                });
            }

            me.floatParent = floatParent;

            // Floating Components as children of Containers must hide when their parent hides.
            if (floatParent) {
                me.mon(me.floatParent, {
                    hide: me.onFloatParentHide,
                    show: me.onFloatParentShow,
                    scope: me
                });
            }

            // If a floating Component is configured to be constrained, but has no configured
            // constrainTo setting, set its constrainTo to be it's ownerCt before rendering.
            if ((me.constrain || me.constrainHeader) && !me.constrainTo) {
                me.constrainTo = floatParent ? floatParent.getTargetEl() : me.container;
            }
        },

        onFloatParentHide: function() {
            this.showOnParentShow = this.isVisible();
            this.hide();
        },

        onFloatParentShow: function() {
            if (this.showOnParentShow) {
                delete this.showOnParentShow;
                this.show();
            }
        },

        /**
         * @private
         * <p>Finds the ancestor Container responsible for allocating zIndexes for the passed Component.</p>
         * <p>That will be the outermost floating Container (a Container which has no ownerCt and has floating:true).</p>
         * <p>If we have no ancestors, or we walk all the way up to the document body, there's no zIndexParent,
         * and the global Ext.WindowManager will be used.</p>
         */
        getZIndexParent: function() {
            var p = this.ownerCt,
                c;

            if (p) {
                while (p) {
                    c = p;
                    p = p.ownerCt;
                }
                if (c.floating) {
                    return c;
                }
            }
        },

        // private
        // z-index is managed by the zIndexManager and may be overwritten at any time.
        // Returns the next z-index to be used.
        // If this is a Container, then it will have rebased any managed floating Components,
        // and so the next available z-index will be approximately 10000 above that.
        setZIndex: function(index) {
            var me = this;
            this.el.setZIndex(index);

            // Next item goes 10 above;
            index += 10;

            // When a Container with floating items has its z-index set, it rebases any floating items it is managing.
            // The returned value is a round number approximately 10000 above the last z-index used.
            if (me.floatingItems) {
                index = Math.floor(me.floatingItems.setBase(index) / 100) * 100 + 10000;
            }
            return index;
        },

        /**
         * <p>Moves this floating Component into a constrain region.</p>
         * <p>By default, this Component is constrained to be within the container it was added to, or the element
         * it was rendered to.</p>
         * <p>An alternative constraint may be passed.</p>
         * @param {Mixed} constrainTo Optional. The Element or {@link Ext.util.Region Region} into which this Component is to be constrained.
         */
        doConstrain: function(constrainTo) {
            var me = this,
                vector = me.getConstrainVector(constrainTo),
                xy;

            if (vector) {
                xy = me.getPosition();
                xy[0] += vector[0];
                xy[1] += vector[1];
                me.setPosition(xy);
            }
        },

        /**
         * Gets the x/y offsets to constrain this float
         * @private
         * @param {Mixed} constrainTo Optional. The Element or {@link Ext.util.Region Region} into which this Component is to be constrained.
         * @return {Array} The x/y constraints
         */
        getConstrainVector: function(constrainTo){
            var me = this,
                el;

            if (me.constrain || me.constrainHeader) {
                el = me.constrainHeader ? me.header.el : me.el;
                constrainTo = constrainTo || (me.floatParent && me.floatParent.getTargetEl()) || me.container;
                return el.getConstrainVector(constrainTo);
            }
        },

        /**
         * Aligns this floating Component to the specified element
         * @param {Mixed} element The element or {@link Ext.Component} to align to. If passing a component, it must
         * be a omponent instance. If a string id is passed, it will be used as an element id.
         * @param {String} position (optional, defaults to "tl-bl?") The position to align to (see {@link Ext.core.Element#alignTo} for more details).
         * @param {Array} offsets (optional) Offset the positioning by [x, y]
         * @return {Component} this
         */
        alignTo: function(element, position, offsets) {
            if (element.isComponent) {
                element = element.getEl();
            }
            var xy = this.el.getAlignToXY(element, position, offsets);
            this.setPagePosition(xy);
            return this;
        },

        /**
         * <p>Brings this floating Component to the front of any other visible, floating Components managed by the same {@link Ext.ZIndexManager ZIndexManager}</p>
         * <p>If this Component is modal, inserts the modal mask just below this Component in the z-index stack.</p>
         * @param {Boolean} preventFocus (optional) Specify <code>true</code> to prevent the Component from being focused.
         * @return {Component} this
         */
        toFront: function(preventFocus) {
            var me = this;

            // Find the floating Component which provides the base for this Component's zIndexing.
            // That must move to front to then be able to rebase its zIndex stack and move this to the front
            if (me.zIndexParent) {
                me.zIndexParent.toFront(true);
            }
            if (me.zIndexManager.bringToFront(me)) {
                if (!Ext.isDefined(preventFocus)) {
                    preventFocus = !me.focusOnToFront;
                }
                if (!preventFocus) {
                    // Kick off a delayed focus request.
                    // If another floating Component is toFronted before the delay expires
                    // this will not receive focus.
                    me.focus(false, true);
                }
            }
            return me;
        },

        /**
         * <p>This method is called internally by {@link Ext.ZIndexManager} to signal that a floating
         * Component has either been moved to the top of its zIndex stack, or pushed from the top of its zIndex stack.</p>
         * <p>If a <i>Window</i> is superceded by another Window, deactivating it hides its shadow.</p>
         * <p>This method also fires the {@link #activate} or {@link #deactivate} event depending on which action occurred.</p>
         * @param {Boolean} active True to activate the Component, false to deactivate it (defaults to false)
         * @param {Component} newActive The newly active Component which is taking over topmost zIndex position.
         */
        setActive: function(active, newActive) {
            if (active) {
                if ((this instanceof Ext.window.Window) && !this.maximized) {
                    this.el.enableShadow(true);
                }
                this.fireEvent('activate', this);
            } else {
                // Only the *Windows* in a zIndex stack share a shadow. All other types of floaters
                // can keep their shadows all the time
                if ((this instanceof Ext.window.Window) && (newActive instanceof Ext.window.Window)) {
                    this.el.disableShadow();
                }
                this.fireEvent('deactivate', this);
            }
        },

        /**
         * Sends this Component to the back of (lower z-index than) any other visible windows
         * @return {Component} this
         */
        toBack: function() {
            this.zIndexManager.sendToBack(this);
            return this;
        },

        /**
         * Center this Component in its container.
         * @return {Component} this
         */
        center: function() {
            var xy = this.el.getAlignToXY(this.container, 'c-c');
            this.setPagePosition(xy);
            return this;
        },

        // private
        syncShadow : function(){
            if (this.floating) {
                this.el.sync(true);
            }
        },

        // private
        fitContainer: function() {
            var parent = this.floatParent,
                container = parent ? parent.getTargetEl() : this.container,
                size = container.getViewSize(false);

            this.setSize(size);
        }
    });