##<iron-selector>
iron-selector is an element which can be used to manage a list of elements
that can be selected. Tapping on the item will make the item selected. The selected indicates
which item is being selected. The default is to use the index of the item.
Example:
<iron-selector selected="0">
<div>Item 1</div>
<div>Item 2</div>
<div>Item 3</div>
</iron-selector>If you want to use the attribute value of an element for selected instead of the index,
set attrForSelected to the name of the attribute. For example, if you want to select item by
name, set attrForSelected to name.
Example:
<iron-selector attr-for-selected="name" selected="foo">
<div name="foo">Foo</div>
<div name="bar">Bar</div>
<div name="zot">Zot</div>
</iron-selector>You can specify a default fallback with fallbackSelection in case the selected attribute does
not match the attrForSelected attribute of any elements.
Example:
<iron-selector attr-for-selected="name" selected="non-existing"
fallback-selection="default">
<div name="foo">Foo</div>
<div name="bar">Bar</div>
<div name="default">Default</div>
</iron-selector>Note: When the selector is multi, the selection will set to fallbackSelection iff
the number of matching elements is zero.
iron-selector is not styled. Use the iron-selected CSS class to style the selected element.
Example:
<style>
.iron-selected {
background: #eee;
}
</style>
...
<iron-selector selected="0">
<div>Item 1</div>
<div>Item 2</div>
<div>Item 3</div>
</iron-selector>