1 2<!--- 3 4This README is automatically generated from the comments in these files: 5iron-overlay-backdrop.html iron-overlay-behavior.html 6 7Edit those files, and our readme bot will duplicate them over here! 8Edit this file, and the bot will squash your changes :) 9 10The bot does some handling of markdown. Please file a bug if it does the wrong 11thing! https://github.com/PolymerLabs/tedium/issues 12 13--> 14 15[](https://travis-ci.org/PolymerElements/iron-overlay-behavior) 16 17_[Demo and API docs](https://elements.polymer-project.org/elements/iron-overlay-behavior)_ 18 19 20##Polymer.IronOverlayBehavior 21 22Use `Polymer.IronOverlayBehavior` to implement an element that can be hidden or shown, and displays 23on top of other content. It includes an optional backdrop, and can be used to implement a variety 24of UI controls including dialogs and drop downs. Multiple overlays may be displayed at once. 25 26### Closing and canceling 27 28A dialog may be hidden by closing or canceling. The difference between close and cancel is user 29intent. Closing generally implies that the user acknowledged the content on the overlay. By default, 30it will cancel whenever the user taps outside it or presses the escape key. This behavior is 31configurable with the `no-cancel-on-esc-key` and the `no-cancel-on-outside-click` properties. 32`close()` should be called explicitly by the implementer when the user interacts with a control 33in the overlay element. When the dialog is canceled, the overlay fires an 'iron-overlay-canceled' 34event. Call `preventDefault` on this event to prevent the overlay from closing. 35 36### Positioning 37 38By default the element is sized and positioned to fit and centered inside the window. You can 39position and size it manually using CSS. See `Polymer.IronFitBehavior`. 40 41### Backdrop 42 43Set the `with-backdrop` attribute to display a backdrop behind the overlay. The backdrop is 44appended to `<body>` and is of type `<iron-overlay-backdrop>`. See its doc page for styling 45options. 46 47### Limitations 48 49The element is styled to appear on top of other content by setting its `z-index` property. You 50must ensure no element has a stacking context with a higher `z-index` than its parent stacking 51context. You should place this element as a child of `<body>` whenever possible. 52 53 54 55##<iron-overlay-backdrop> 56 57`iron-overlay-backdrop` is a backdrop used by `Polymer.IronOverlayBehavior`. It should be a 58singleton. 59 60### Styling 61 62The following custom properties and mixins are available for styling. 63 64| Custom property | Description | Default | 65| --- | --- | --- | 66| `--iron-overlay-backdrop-background-color` | Backdrop background color | #000 | 67| `--iron-overlay-backdrop-opacity` | Backdrop opacity | 0.6 | 68| `--iron-overlay-backdrop` | Mixin applied to `iron-overlay-backdrop`. | {} | 69| `--iron-overlay-backdrop-opened` | Mixin applied to `iron-overlay-backdrop` when it is displayed | {} | 70 71 72
){kind=link}