PopupButton

The class, tag, or template used for the backdrop part - the optional element shown behind the popup.

This can help focus the user's attention on the overlay content. Additionally, a backdrop can be used to absorb clicks on background page elements. For example, Dialog uses ModalBackdrop as an overlay backdrop in such a way.

Close the component (if not already closed).

Some components like AlertDialog want to indicate why or how they were closed. To support such scenarios, you can supply a value to the optional closeResult parameter. This closeResult will be made available in the whenClosed promise and the state.closeResult member.

True if the element is currently closed.

Raised when the component closes.

True if the element has completely closed.

For components not using asynchronous open/close effects, this property returns the same value as the closed property. For elements that have a true value of state.openCloseEffects (e.g., elements using TransitionEffectMixin), this property returns true only if state.effect is "close" and state.effectPhase is "after".

True if the component is disabled, false (the default) if not.

The value of this property will be reflected to the disabled attribute so that it can be referenced in CSS. Note that this non-native implementation of the disabled attribute will not trigger the :disabled CSS pseudo-class, so your style rules will have to reference the presence or absence of the disabled attribute. That is, instead of writing

my-component:disabled { ... }

write this instead

my-component[disabled] { ... }

Like the native disabled attribute, this attribute is boolean. That means that it's existence in markup sets the attribute, even if set to an empty string or a string like "false".

The class, tag, or template used to create the frame part – the popup's primary content.

The frame element can be used to provide a border around the popup content, and to provide visual effects such as a drop-shadow to help distinguish popup content from background page elements.

The alignment of the popup with respect to the source button.

• start: popup and source are aligned on the leading edge according to the text direction
• end: popup and source are aligned on the trailing edge according to the text direction
• left: popup and source are left-aligned
• right: popup and source are right-aligned
• `stretch: both left and right edges are aligned

The default state for the component. This can be extended by mixins and classes to provide additional default state.

A convenient shortcut for looking up an element by ID in the component's Shadow DOM subtree.

Example: if component's template contains a shadow element <button id="foo">, you can use the reference this[internal.ids].foo to obtain the corresponding button in the component instance's shadow tree. The ids property is simply a shorthand for getElementById, so this[internal.ids].foo is the same as this.shadowRoot.getElementById('foo').

See the symbols documentation for details.

Render the indicated changes in state to the DOM.

The default implementation of this method does nothing. Override this method in your component to update your component's host element and any shadow elements to reflect the component's new state. See the rendering example.

Be sure to call super in your method implementation so that your component's base classes and mixins have a chance to perform their own render work.

Render any pending component changes to the DOM.

This method does nothing if the state has not changed since the last render call.

ReactiveMixin will invoke this method following a setState call; you should not need to invoke this method yourself.

This method invokes all internal render methods, then invokes componentDidMount (for first render) or componentDidUpdate (for subsequent renders).

Update the component's state by merging the specified changes on top of the existing state. If the component is connected to the document, and the new state has changed, this returns a promise to asynchronously render the component. Otherwise, this returns a resolved promise.

The component's current state.

The returned state object is immutable. To update it, invoke internal.setState.

It's extremely useful to be able to inspect component state while debugging. If you append ?elixdebug=true to a page's URL, then ReactiveMixin will conditionally expose a public state property that returns the component's state. You can then access the state in your browser's debug console.

Open the element (if not already opened).

True if the element is currently opened.

Raised when the component opens.

Raised when the opened/closed state of the component changes.

The class, tag, or template used to create the popup part – the element responsible for displaying the popup and handling overlay behavior.

The preferred direction for the popup.

• above: popup should appear above the source
• below: popup should appear below the source

The class, tag, or template used to create the source part - the button (or other element) the user can tap/click to invoke the popup.

Temporarily suppress visibility of the keyboard focus until the next keydown event.

This can be useful in components like Menu that actively manage where the focus is in response to mouse hover activity. If the user uses the keyboard to invoke a menu, then changes to using the mouse, it can be distracting to see the focus indicator moving as well. In such situations, the component can invoke this method (e.g., in response to mousemove) to temporarily suppress focus visibility.

Toggle the open/close state of the element.

This method can be used as an alternative to listening to the "opened-changed" event, particularly in situations where you want to only handle the next time the component is closed.