if (!dojo._hasResource["dijit._base.popup"]) { // _hasResource checks added by
												// build. Do not use
												// _hasResource directly in your
												// code.
	dojo._hasResource["dijit._base.popup"] = true;
	dojo.provide("dijit._base.popup");

	dojo.require("dijit._base.focus");
	dojo.require("dijit._base.place");
	dojo.require("dijit._base.window");

	dijit.popup = new function() {
		// summary:
		// This class is used to show/hide widgets as popups.
		//

		var stack = [], beginZIndex = 1000, idGen = 1;

		this.open = function(/* Object */args) {
			// summary:
			// Popup the widget at the specified position
			//
			// args: Object
			// popup: Widget
			// widget to display,
			// parent: Widget
			// the button etc. that is displaying this popup
			// around: DomNode
			// DOM node (typically a button); place popup relative to this node
			// orient: Object
			// structure specifying possible positions of popup relative to
			// "around" node
			// onCancel: Function
			// callback when user has canceled the popup by
			// 1. hitting ESC or
			// 2. by using the popup widget's proprietary cancel mechanism (like
			// a cancel button in a dialog);
			// ie: whenever popupWidget.onCancel() is called, args.onCancel is
			// called
			// onClose: Function
			// callback whenever this popup is closed
			// onExecute: Function
			// callback when user "executed" on the popup/sub-popup by selecting
			// a menu choice, etc. (top menu only)
			//
			// examples:
			// 1. opening at the mouse position
			// dijit.popup.open({popup: menuWidget, x: evt.pageX, y:
			// evt.pageY});
			// 2. opening the widget as a dropdown
			// dijit.popup.open({parent: this, popup: menuWidget, around:
			// this.domNode, onClose: function(){...} });
			//
			// Note that whatever widget called dijit.popup.open() should also
			// listen to it's own _onBlur callback
			// (fired from _base/focus.js) to know that focus has moved
			// somewhere else and thus the popup should be closed.

			var widget = args.popup, orient = args.orient || {
				'BL' : 'TL',
				'TL' : 'BL'
			}, around = args.around, id = (args.around && args.around.id)
					? (args.around.id + "_dropdown")
					: ("popup_" + idGen++);

			// make wrapper div to hold widget and possibly hold iframe behind
			// it.
			// we can't attach the iframe as a child of the widget.domNode
			// because
			// widget.domNode might be a <table>, <ul>, etc.
			var wrapper = dojo.doc.createElement("div");
			wrapper.id = id;
			wrapper.className = "dijitPopup";
			wrapper.style.zIndex = beginZIndex + stack.length;
			wrapper.style.visibility = "hidden";
			if (args.parent) {
				wrapper.dijitPopupParent = args.parent.id;
			}
			dojo.body().appendChild(wrapper);

			widget.domNode.style.display = "";
			wrapper.appendChild(widget.domNode);

			var iframe = new dijit.BackgroundIframe(wrapper);

			// position the wrapper node
			var best = around ? dijit.placeOnScreenAroundElement(wrapper,
					around, orient, widget.orient ? dojo
							.hitch(widget, "orient") : null) : dijit
					.placeOnScreen(wrapper, args, orient == 'R' ? ['TR', 'BR',
									'TL', 'BL'] : ['TL', 'BL', 'TR', 'BR']);

			wrapper.style.visibility = "visible";
			// TODO: use effects to fade in wrapper

			var handlers = [];

			// Compute the closest ancestor popup that's *not* a child of
			// another popup.
			// Ex: For a TooltipDialog with a button that spawns a tree of
			// menus, find the popup of the button.
			function getTopPopup() {
				for (var pi = stack.length - 1; pi > 0
						&& stack[pi].parent === stack[pi - 1].widget; pi--);
				return stack[pi];
			}

			// provide default escape and tab key handling
			// (this will work for any widget, not just menu)
			handlers.push(dojo.connect(wrapper, "onkeypress", this, function(
							evt) {
						if (evt.keyCode == dojo.keys.ESCAPE && args.onCancel) {
							args.onCancel();
						} else if (evt.keyCode == dojo.keys.TAB) {
							dojo.stopEvent(evt);
							var topPopup = getTopPopup();
							if (topPopup && topPopup.onCancel) {
								topPopup.onCancel();
							}
						}
					}));

			// watch for cancel/execute events on the popup and notify the
			// caller
			// (for a menu, "execute" means clicking an item)
			if (widget.onCancel) {
				handlers.push(dojo.connect(widget, "onCancel", null,
						args.onCancel));
			}

			handlers.push(dojo.connect(widget, widget.onExecute
							? "onExecute"
							: "onChange", null, function() {
						var topPopup = getTopPopup();
						if (topPopup && topPopup.onExecute) {
							topPopup.onExecute();
						}
					}));

			stack.push({
						wrapper : wrapper,
						iframe : iframe,
						widget : widget,
						parent : args.parent,
						onExecute : args.onExecute,
						onCancel : args.onCancel,
						onClose : args.onClose,
						handlers : handlers
					});

			if (widget.onOpen) {
				widget.onOpen(best);
			}

			return best;
		};

		this.close = function(/* Widget */popup) {
			// summary:
			// Close specified popup and any popups that it parented
			while (dojo.some(stack, function(elem) {
						return elem.widget == popup;
					})) {
				var top = stack.pop(), wrapper = top.wrapper, iframe = top.iframe, widget = top.widget, onClose = top.onClose;

				if (widget.onClose) {
					widget.onClose();
				}
				dojo.forEach(top.handlers, dojo.disconnect);

				// #2685: check if the widget still has a domNode so ContentPane
				// can change its URL without getting an error
				if (!widget || !widget.domNode) {
					return;
				}
				dojo.style(widget.domNode, "display", "none");
				dojo.body().appendChild(widget.domNode);
				iframe.destroy();
				dojo._destroyElement(wrapper);

				if (onClose) {
					onClose();
				}
			}
		};
	}();

	dijit._frames = new function() {
		// summary: cache of iframes
		var queue = [];

		this.pop = function() {
			var iframe;
			if (queue.length) {
				iframe = queue.pop();
				iframe.style.display = "";
			} else {
				if (dojo.isIE) {
					var html = "<iframe src='javascript:\"\"'"
							+ " style='position: absolute; left: 0px; top: 0px;"
							+ "z-index: -1; filter:Alpha(Opacity=\"0\");'>";
					iframe = dojo.doc.createElement(html);
				} else {
					var iframe = dojo.doc.createElement("iframe");
					iframe.src = 'javascript:""';
					iframe.className = "dijitBackgroundIframe";
				}
				iframe.tabIndex = -1; // Magic to prevent iframe from getting
										// focus on tab keypress - as style
										// didnt work.
				dojo.body().appendChild(iframe);
			}
			return iframe;
		};

		this.push = function(iframe) {
			iframe.style.display = "";
			if (dojo.isIE) {
				iframe.style.removeExpression("width");
				iframe.style.removeExpression("height");
			}
			queue.push(iframe);
		}
	}();

	// fill the queue
	if (dojo.isIE && dojo.isIE < 7) {
		dojo.addOnLoad(function() {
					var f = dijit._frames;
					dojo.forEach([f.pop()], f.push);
				});
	}

	dijit.BackgroundIframe = function(/* DomNode */node) {
		// summary:
		// For IE z-index schenanigans. id attribute is required.
		//
		// description:
		// new dijit.BackgroundIframe(node)
		// Makes a background iframe as a child of node, that fills
		// area (and position) of node

		if (!node.id) {
			throw new Error("no id");
		}
		if ((dojo.isIE && dojo.isIE < 7)
				|| (dojo.isFF && dojo.isFF < 3 && dojo.hasClass(dojo.body(),
						"dijit_a11y"))) {
			var iframe = dijit._frames.pop();
			node.appendChild(iframe);
			if (dojo.isIE) {
				iframe.style.setExpression("width", "document.getElementById('"
								+ node.id + "').offsetWidth");
				iframe.style.setExpression("height",
						"document.getElementById('" + node.id
								+ "').offsetHeight");
			}
			this.iframe = iframe;
		}
	};

	dojo.extend(dijit.BackgroundIframe, {
				destroy : function() {
					// summary: destroy the iframe
					if (this.iframe) {
						dijit._frames.push(this.iframe);
						delete this.iframe;
					}
				}
			});

}