Frame

Frames are parent items that can group and hold together other items on a board, such as shapes, text, images, and so on.
When an item is a child of a parent frame, the child positioning reference is relative to the parent frame.

Frames help structure and organize board content:

  • They enable exporting board content to PDF, or to save it as a presentation.
  • They are indexed; they make it easier to search for and find board content.
  • When presentation mode is enabled on a board, indexed frames define the sequence of the slides in the presentation.

When creating or updating a frame item, you can define its dimensions in the following way:

  • Set or update only width.
    Default width: 100 dp
  • Set or update onlyheight.
    Default height: 100 dp
  • Set or update width and height at the same time.

ℹ️ Note:

  • If you resize a parent frame containing child items, the Web SDK throws an error if one or more children fall outside the parent frame after resizing it.
    This isn't allowed, because it would break the parent/child relationship between the items.
    To break the relationship, explicitly remove the child item(s) from the parent frame.

Example:

const frame = await miro.board.createFrame({
  title: 'This frame ratio is 16:9',
  style: {
    fillColor: '#ffffff',
  },
  x: 0, // Default value: horizontal center of the board
  y: 0, // Default value: vertical center of the board
  width: 800,
  height: 450,
});

// Output the created item to the developer console
console.log(frame);

Frame item:

A frame parent item containing a sticky note as a child item.
Figure 1. A frame parent item containing a sticky note as a child item.

Properties

width

number

Width of the item in dp.

See also:


height

number

Height of the item in dp.

See also:


title

string

A short text header for the frame.
The text must be shorter than 6000 characters.

title supports only plain text.


showContent

boolean

showContent enables to programmatically hide or reveal the content inside a frame.
The functionality works like the show frame and hide frame options available on the item context menu when the frame is selected on the board UI.

showContent is a boolean property:

  • showContent: true: all the content inside the frame is visible.
  • showContent: false: all the content inside the frame is hidden.
    On the board UI, an overlay is displayed over the frame to visually notify board users that they cannot view the frame content.

Default: true

ℹ️ Note:

  • Hiding and revealing the content inside frames is only available to board owners and co-owners on Consultant and Enterprise plans.
    If your app attempts to toggle the visibility of content inside a frame with showContent for users who are on different subscription plans and who aren't board owners or co-owners, the operation throws an error.


Figure 1. showContent: true reveals the content inside the frame.


Figure 2. showContent: false hides the content inside the frame.


childrenIds

Array<string>

An array of unique identifiers.
The IDs represent child items inside the frame.
They help retrieve child items inside a parent item.


style

{ fillColor: string }

The style object groups properties that define the layout, the look and feel of specific elements of an item, when it's displayed on the board.
For example: background color, font family, font type, horizontal and vertical alignment of the text, text color, and so on.

The Miro Web SDK doesn't support all standard style, yet. Additional styles will be included in future releases.

style data structure:

fillColor

Hex value representing the background color that fills the area of the frame.

Default: no fill (transparent background)


id

readonly string

Unique ID of the item, assigned automatically upon creation.

Example: 3658432978520043388


x

number

The x-axis coordinate of an item is the horizontal distance in dp of the center point of the item from the center point of the board.

The center point of the board has x: 0 and y: 0 coordinates.

Default: 0

See also:


y

number

The y-axis coordinate of an item is the vertical distance in dp of the center point of the item from the center point of the board.

The center point of the board has x: 0 and y: 0 coordinates.

Default: 0

See also:


type

readonly 'frame'

Defines the type of item.
Item type is useful to retrieve specific items from a board. For example, you can fetch all card and shape items from the board, and then carry out an action on them.

Example:

// Get all items from the board
const items = await miro.board.get();

// Count all card and shape items on the board
let cards = 0;
let shapes = 0;

items.forEach((items) => {
  switch (items.type) {
    case 'card':
      cards++;
    case 'shape':
      shapes++;
  }
});

// Output to the console the total amount of card and shape items
console.log(`The current board has ${cards} cards and ${shapes} shapes.`);

parentId

readonly 'null' | string

If an item is a child of another item, the child's parentId returns the unique identifier of the corresponding parent item.
If an item has no parent, its parentId is null.

You can use the value to retrieve a tree structure when items are nested inside containers.
For example, sticky notes inside frames or text items inside mindmaps.


origin

'center'

origin marks:

  • The positioning reference point of a board item.
    This is the point used to calculate the x and y coordinates of an item when it's positioned on the board, or when it's a child inside a parent item.
  • The rotation pivot point of a board item that supports rotation.

origin accepts only one value: center.
Any other value throws an error.


relativeTo

'canvas_center' | 'parent_top_left' | 'parent_center'

The relativeTo property affects the x and y coordinate values of a board item.
relativeTo defines the positioning reference of a board item, which can be:

Depending on whether an item is a child of a parent item or not, relativeTo can have one of the following values:

ValueDescriptionOn the board UI
canvas_centerThe item is positioned on the board, and it's not a child of another item.
The x and y coordinate values of the item are relative to the center of the board.

Figure 1. The relativeTo property of the board item—a sticky note in the example image—is set to canvas_center. The same mechanism applies to and works in the same way for all supported board items.
parent_top_leftThe item is positioned on the board, and it is a child of a parent item. For example, a parent frame.
The x and y coordinate values of the child item are relative to the top-left corner of the parent item).

Figure 2. The relativeTo property of the board item—a sticky note in the example image—is set to parent_top_left. The same mechanism applies to and works in the same way for all supported board items.
parent_centerExperimental feature Experimental feature

The item is positioned on the board, and it is a child of a parent mind map node.
The x and y coordinate values of the item are relative to the center of the parent mind map node item.

Figure 3. The relativeTo property of the child mind map nodes is set to parent_center.

See also:


linkedTo?

string

linkedTo is the namespace that enables links to be associated to items on the board.

When this property is utilized, the associated item will display an arrow icon on its top right corner. On click, this icon will navigate to the associated link.

For links that point to another item on the same board, the viewport will automatically move to that item when true is returned.

For links that point to an item on a separate board or an external url, a new tab tab will be opened.

Note: Items of type tag do not support the linkedTo property.

To link an item to another item on the same board, a valid url with an item id must be specified:

const [geoCard] = await miro.board.get({type: 'card'});

const widgetId = `00000000000000000`;
const boardId = 'xxxxxxxxxxx';

// Generate url based on boardId and widgetId
geoCard.linkedTo = `https://miro.com/app/board/${xxxxxxxxxxx}/?moveToWidget=${widgetId}`;

// OR you can use relative URL
geoCard.linkedTo = `/app/board/${xxxxxxxxxxx}/?moveToWidget=${widgetId}`;

// OR you can generate url based on current URL by simply change of query param
const searchParams = new URLSearchParams(window.location.search);
searchParams.set('moveToWidget', widgetId);
const newRelativePathQuery = `${window.location.pathname}?${searchParams.toString()}`;
geoCard.linkedTo = newRelativePathQuery;

To unlink an item to the provided url, set the property to undefined or pass an empty string "":

const [geoCard] = await miro.board.get({type: 'card'});
// Unlink the widget
geoCard.linkedTo = '';
// or
geoCard.linkedTo = undefined;

await geoCard.sync();

console.log(geoCard.linkedTo); // will return empty string: ''

createdAt

readonly string

Timestamp

Date and time when the item was created.

Format: UTC, ISO 8601.
Includes a trailing Z offset.

Example: 2021-05-18T07:59:01Z

ℹ️ Note:

  • Timestamps indicating creation and update times are always in UTC time, regardless of the time offset configured on the machine where the app runs or where the code is executed.

createdBy

readonly string

Miro users are automatically assigned a unique ID.

createdBy contains the ID of the user who created the item.

Example: 3658432978520043388


modifiedAt

readonly string

Timestamp

Date and time when the item was last modified.

Format: UTC, ISO 8601.
Includes a trailing Z offset.

Example: 2021-05-18T07:59:01Z

ℹ️ Note:

  • Timestamps indicating creation and update times are always in UTC time, regardless of the time offset configured on the machine where the app runs or where the code is executed.

modifiedBy

readonly string

Miro users are automatically assigned a unique ID.

modifiedBy contains the ID of the user who applied the most recent edit to the item.

Example: 3658432978520043388

Methods

add(...)

(item: T) => Promise<T>
🔒 Requires scope: boards:write

Adds an item to a frame as a child.
The frame becomes the corresponding parent.

The add() method takes a board item as an argument.
To add a board item to a frame with add(), the item to add must:

  • Exist on the board.
  • Be located inside the frame.

add() establishes a parent/child relationship between the containing frame and the items inside it.
After calling add():

This enables repositioning a frame on the board along with its children, as they keep the same relative position inside the parent frame.
It also affects the positioning reference of the child item, because its x and y values are no longer relative to the center of the board.
After adding an item to a frame, the x and y coordinates of the child item inside the parent frame mark the center point of the child, relative to the top-left corner of the parent frame.

Adding a board item to a frame as a child can fail if:

  • The parent frame doesn't exist.
  • The child item is located outside the bounds of the parent frame.
  • The child item is already a child inside a different frame.

remove(...)

(item: T) => Promise<void>
🔒 Requires scope: boards:write

Removes a child item from a frame.
The method removes the parent-child relationship between the items.
Both items still exist on the board as independent, detached items.

This affects the positioning reference of the item, because its x and y values are no longer relative to the top-left corner of the frame.
After removing an item from a frame, the item's x and y coordinates mark the center point of the item, relative to the center of the board.

The frame.remove() method takes an item as an argument.
The promise that the method returns can fail if:

  • The child item you're trying to remove doesn't exist.
  • The item you're trying to remove isn't a child of the frame.
  • The frame doesn't exist.

Example:

// Create a frame.
const frame = await miro.board.createFrame({
  title: 'this frame ratio is 16:9',
  style: {
    fillColor: '#FFFFFF',
  },
  width: 800,
  height: 450,
  x: 4100,
  y: 4200,
});

// Create a text item, and position it inside the frame.
const text = await miro.board.createText({
  content: 'this is a piece of text',
  style: {
    fillColor: '#fff9b1', // Light yellow
  },
  x: frame.x + 180,
  y: frame.y + 10,
});

// Create a shape item, and position it inside the frame.
const shape = await miro.board.createShape({
  width: 200,
  height: 250,
  x: frame.x + 20,
  y: frame.y + 50,
  style: {
    fillColor: '#FF0000',
  },
});

// Add the text and the shape items as children of the parent frame.
await frame.add(text);
await frame.add(shape);

// Move the frame on the board.
// The children items move along with the frame:
// their coordinates are relative to the top-left corner of the frame.
frame.x = -400;
frame.y = -500;
await frame.sync();

// Update the child shape position inside the frame
// by specifying relative coordinates.
const shapes = await miro.board.get({type: 'shape'});
await Promise.all(
  shapes.map((child) => {
    child.x += 150;
    child.y += 200;
    return child.sync();
  }),
);

// Remove the parent/child relationship between frame and text item.
await frame.remove(text);

// Move the frame on the board.
// The text item doesn't move along with the frame:
// its coordinates are relative to the center of the board.
frame.x += 400;
frame.y += 500;
await frame.sync();

// Remove the text item from the board
await miro.board.remove(text);

// Remove the frame from the board
await miro.board.remove(frame);

getChildren(...)

() => Promise<Array<Item | Group>>
🔒 Requires scope: boards:read
🚦 Rate limit: Level 3

Returns an array containing all the child items inside a parent frame.
If a frame has no children, the method returns an empty array.

Example:

// Specify all frame items on the board
let frames = await miro.board.get({type: 'frame'});

// Log to the console the child items of the frames
for (const frame of frames) {
  const children = await frame.getChildren();
  console.log(children);
}

sync(...)

() => Promise<void>
🔒 Requires scope: boards:write

sync propagates to the board any changes to item and tag properties.
After updating the properties of an item or a tag, sync it with the board to:

  • Propagate to the board the changes applied to the item or to the tag.
  • Make the changes visible on the board.

All board items and tags require sync to make any changes to their properties visible on the board.

For more information and examples, see Update and sync item properties.

Example:
(The code example updates a text item using sync.
The same mechanism applies to and works in the same way for all supported board items.)

// Create an item.
// In this case, a text item.
const text = await miro.board.createText({
  content: '<p>This is a piece of text to remind me that I always finish what I ...</p>',
  style: {
    fillColor: 'transparent',
    textAlign: 'left',
  },
  x: 0,
  y: 0,
  width: 450,
  rotation: 0.0,
});

// Update the board item by modifying the values of its properties.
// In the text item case, the updated properties modify content, background color, and rotation of the item.
text.content = 'A fourteneer is "A line that rumbles on like this for being a bit too long."';
text.style.fillColor = '#a9fe65';
text.rotation = 180.0;

// Call 'sync' to make the changed board item properties visible on the board.
await text.sync();

// Output the updated board item to the developer console.
console.log(text);

Example:
(The code example updates a tag using sync.
The same mechanism applies to and works in the same way for all supported board items.)

// Create a tag.
const todo = await miro.board.createTag({
  title: 'todo',
  color: 'yellow',
});

// Create a sticky note and attach the tag to it.
const stickyNote = await miro.board.createStickyNote({
  content: 'sticky note with tag: "todo"',
  tagIds: [todo.id],
});
console.log(stickyNote.tagIds); // => ['3074457345627244742']

// Update the tag properties: title and color.
todo.title = "won't fix";
todo.color = 'green';

// Call 'sync' to make the changed tag properties visible on the board.
await todo.sync();

// Output the updated tag to the developer console.
console.log(todo);

getMetadata(...)

(key?: string) => Promise<T>
🔒 Requires scope: boards:read
🚦 Rate limit: Level 1

Fetches board item metadata, stored per app, for the specified metadata key.
The response contains the metadata value assigned to the requested key.

To fetch all the metadata for a board item, invoke the method without passing any arguments.
The response contains all the metadata associated with the board item as key/value pairs.

An app can access only the metadata that it sets.
It cannot access metadata set by other apps.

getMetadata and setMetadata are available for the following board items:

  • Card
  • Connector
  • Embed
  • Image
  • Preview
  • Shape
  • Sticky note
  • Text

The methods aren't available for the following board items:

ℹ️ Note:

⚠️ Warning:

  • Total ItemMetadata storage limit: 6 KB per item.

Example:

// Get the board item you want to retrieve metadata from.
const [geoCard] = await miro.board.get({type: 'card'});

// Set item metadata for an imaginary geocaching game, and store it to the retrieved card item.
await geoCard.setMetadata('leaderboard', ['Ziltoid', 'Howard', 'Paul']);

// Get the specific 'leaderboard' metadata from the card item.
const leaderboard = await geoCard.getMetadata('leaderboard');

// Get all the metadata from the card item by passing no arguments.
await geoCard.getMetadata();

setMetadata(...)

(key: string, value?: title="Json">Json) => Promise<T>
🔒 Requires scope: boards:write

Adds board item metadata to make it available on the board that the app runs on.
An app can access only the board item metadata that it sets.
It cannot access metadata set by other apps.

Board item metadata is stored in the item it refers to. Therefore:

  • When duplicating an item, the metadata is copied to the new item.
  • When deleting an item, the corresponding metadata is removed with the deleted item.

Board item metadata is synced across, and available to, all the users who can:

  • Access and view the board that the app is running on, AND
  • Run the app on the board.

ItemMetadata is a key/value-pair object. It can contain values with the following data types:

  • string
  • number
  • boolean
  • Object
  • Array
  • null
  • undefined

getMetadata and setMetadata are available for the following board items:

  • Card
  • Connector
  • Embed
  • Image
  • Preview
  • Shape
  • Sticky note
  • Text

The methods aren't available for the following board items:

To overwrite an existing key inside ItemMetadata:

  • Pass the same key multiple times with different values. Only the last/most recent value is stored with the key.

To remove a key from ItemMetadata:

  • Set the value of the existing key to either null, or undefined.
    This clears the key. If you call getMetadata(key) to retrieve a key that has been set to null or undefined, the method returns undefined.

ℹ️ Note:

⚠️ Warning:

  • Total ItemMetadata storage limit: 6 KB per item.

Example:

// Get the board item you want to set metadata to.
const [geoCard] = await miro.board.get({type: 'card'});

// Set item metadata for an imaginary geocaching game, and store it to the retrieved card item.
await geoCard.setMetadata('geoData', {
  name: 'null',
  coordinates: {
    latitude: '33.950278',
    longitude: '-105.314167',
  },
  lastFound: '1947-07-08',
  content: true,
  difficulty: 5,
  keywords: ['x-files', 'truth-is-out-there', 'area-51', 'roswell', 'aliens'],
  geoCache: [
    {
      name: 'UFO',
      description: 'Severely damaged unidentified flying object. ',
    },
    {
      name: 'Alien',
      description: 'Remains of an alien life form.',
    },
    {
      name: 'Artifacts',
      description: 'Tools, equipment, and other items found at the crash site.',
    },
    {
      name: 'Edibles',
      description: 'The alien was likely as high as a kite when they crashed. Typical.',
    },
  ],
});

// Get the specific 'geoData' metadata from the card item.
// The response contains the metadata value assigned to the key.
const geoCardGeoData = await geoCard.getMetadata('geoData');

// Get all the metadata from the card item.
// The response contains all the metadata assigned to the board item as key/value pairs.
const geoCardAllMetaData = await geoCard.getMetadata();

// Clear the metadata about the imaginary geocaching game in one of the following ways:
// 1. Assign 'geoData' an empty object.
await miro.board.setMetadata('geoData', {});
// 2. Set 'geoData' to 'undefined'.
await miro.board.setMetadata('geoData', undefined);
// 3. Set 'geoData' to 'null'.
await miro.board.setMetadata('geoData', null);

goToLink(...)

() => Promise<boolean>
🔒 Requires scope: boards:read

goToLink navigates to the provided link associated with the item on a board.

For links that point to another item on the same board, the viewport will automatically move to that item when true is returned.

For links that point to an item on a separate board or an external url, a new tab tab will be opened.

Returns:

Promise<boolean>

  • true: Link is successfully associated with the item, navigation is triggered, and the linkedTo property contains a valid value.
  • false: Link is not successfully associated to the item due to an invalid or missing linkedTo property, and no navigation is triggered.

Example:

const [geoCard] = await miro.board.get({type: 'card'});

// Link item to some url
geoCard.linkedTo = 'https://google.com';

// Update widget props and apply changes
await geoCard.sync();

// Navigate to https://google.com (value of `linkedTo` property)
await geoCard.goToLink();

bringToFront(...)

() => Promise<void>
🔒 Requires scope: boards:write
🚦 Rate limit: Level 1

In a stack of items, this method brings an item to the front so that it is at the top of the stack.
When the item is at the front, it is fully visible; The item can partially or completely hide underlying items in the same stack.

ℹ️ Note:

  • Frame items don't support the bringToFront() method.
    As a frame item acts as a parent that can contain other items, a frame item is always at the back, relative to any other items on the board.
    The only object behind a frame is the board itself.

Example:

// Create three sticky notes
const first = await miro.board.createStickyNote({
  content: 'first',
});

const second = await miro.board.createStickyNote({
  content: 'second',
});

const third = await miro.board.createStickyNote({
  content: 'third',
});

// Bring the first sticky note to the front of the board.
await first.bringToFront();

sendToBack(...)

() => Promise<void>
🔒 Requires scope: boards:write
🚦 Rate limit: Level 1

In a stack of items, it sends an item to the back so that it is at the bottom of the stack.
When it is at the back, item is partially or completely hidden by overlying items in the same stack.

ℹ️ Note:

  • Frame items don't support the sendToBack() method.
    As a frame item acts as a parent that can contain other items, a frame item is always at the back, relative to any other items on the board.
    The only object behind a frame is the board itself.

Example:

// Create three sticky notes
const first = await miro.board.createStickyNote({
  content: 'first',
});

const second = await miro.board.createStickyNote({
  content: 'second',
});

const third = await miro.board.createStickyNote({
  content: 'third',
});

// Send the third sticky note to the back of the board
await third.sendToBack();

bringInFrontOf(...)

(target: BaseMixin) => Promise<void>
🔒 Requires scope: boards:write
🚦 Rate limit: Level 1

In a stack of items, this method sends an item in front of another item (target).
When an item is moved to the front, the item can partially or completely hide underlying items in the same stack.

ℹ️ Note:

  • As this method implements relative positioning, you can use this method to place items in front or behind other items.
    If you want to send an item all the way to the front,
    you can use the method bringToFront(), which places the item at the top of the stack.
  • Frame items don't support the bringInFrontOf() method.
    As a frame item acts as a parent that can contain other items, a frame item is always at the back, relative to any other items on the board.
    The only object behind a frame is the board itself.

Example:

// Create three sticky notes
const first = await miro.board.createStickyNote({
  content: 'first',
});

const second = await miro.board.createStickyNote({
  content: 'second',
});

const third = await miro.board.createStickyNote({
  content: 'third',
});

// Bring the first sticky note in front of second.
await first.bringInFrontOf(second);

sendBehindOf(...)

(target: BaseMixin) => Promise<void>
🔒 Requires scope: boards:write
🚦 Rate limit: Level 1

In a stack of items, this method sends an item behind another item (target).
When an item is moved to the back, the item can be partially or completely hidden by the overlying items in the top of the same stack.

ℹ️ Note:

  • As this method implements relative positioning, you can use this method to place items in front or behind other items.
    If you want to send an item all the way to the back,
    you can use the method sendToBack(), which places the item at the bottom of the stack.
  • Frame items don't support the sendBehindOf() method.
    As a frame item acts as a parent that can contain other items, a frame item is always at the back, relative to any other items on the board.
    The only object behind a frame is the board itself.

Example:

// Create three sticky notes
const first = await miro.board.createStickyNote({
  content: 'first',
});

const second = await miro.board.createStickyNote({
  content: 'second',
});

const third = await miro.board.createStickyNote({
  content: 'third',
});

// Send the third sticky note behind the second one
await third.sendBehindOf(second);

getLayerIndex(...)

() => Promise<number>
🔒 Requires scope: boards:read

The getLayerIndex() method returns the position of an item in the item stack.

Items in a stack are layered on top of each other based on their layer index value. An item with a higher layer index appears above items with lower layer index values.

Each item on the board has a layer index position in the stack. The higher the layer index value, the "closer" to the user the item appears.

For example, with three items on the board - first, second, and third - their initial layer index values might be:
first[0], second[1], third[2].

The item with layerIndex === 2 (third) will be fully visible at the top of the stack. The item with layerIndex === 1 (second) may be partially hidden by the item above it. And the item with layerIndex === 0 (first) may be fully hidden by the items above it.

Returns:

  • Promise<number> - calling getLayerIndex() allows you get the position of a specific item in the stack.

ℹ️ Note:

  • The item stack is zero indexed.
  • Frame items don't support the getLayerIndex() method.
    As a frame item acts as a parent that can contain other items, a frame item is always at the back, relative to any other items on the board.
    The only object behind a frame is the board itself.

Example:

// Create three sticky notes.
// Sticky notes are created on top of each other in the creation order, with the layer index equal to the creation index.
const first = await miro.board.createStickyNote({
  content: 'first',
});

const second = await miro.board.createStickyNote({
  content: 'second',
});

const third = await miro.board.createStickyNote({
  content: 'third',
});

await third.getLayerIndex(); // returns 2

getConnectors(...)

() => Promise<Array<Connector>>
🔒 Requires scope: boards:read
🚦 Rate limit: Level 3

The getConnectors() method returns an array of connector items attached to the current item. The connectors returned correspond to the ids in the connectorIds property of the item.

Example:

// Create two sticky notes linked by a connector.
const startItem = await miro.board.createStickyNote({
  content: 'start',
});

const endItem = await miro.board.createStickyNote({
  content: 'end',
  x: 500,
});

const connector = await miro.board.createConnector({
  start: {
    item: startItem.id,
  },
  end: {
    item: endItem.id,
  },
});

// sync() updates the connectorIds property in startItem
await startItem.sync();

const connectors = await startItem.getConnectors(); // returns [connector]

All properties

PropertyType
childrenIds
Array<string>
createdAt
readonly string
createdBy
readonly string
groupId?
readonly string
height
number
id
readonly string
linkedTo?
string
modifiedAt
readonly string
modifiedBy
readonly string
origin
'center'
parentId
readonly 'null' | string
relativeTo
'canvas_center' | 'parent_top_left' | 'parent_center'
showContent
boolean
style
{ fillColor: string }
title
string
type
readonly 'frame'
width
number
x
number
y
number
add(...)
(item: T) => Promise<T>
bringInFrontOf(...)
(target: BaseMixin) => Promise<void>
bringToFront(...)
() => Promise<void>
getChildren(...)
() => Promise<Array<Item | Group>>
getConnectors(...)
() => Promise<Array<Connector>>
getLayerIndex(...)
() => Promise<number>
getMetadata(...)
(key?: string) => Promise<T>
goToLink(...)
() => Promise<boolean>
remove(...)
(item: T) => Promise<void>
sendBehindOf(...)
(target: BaseMixin) => Promise<void>
sendToBack(...)
() => Promise<void>
setMetadata(...)
(key: string, value?: title="Json">Json) => Promise<T>
sync(...)
() => Promise<void>