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Viewport

The 💠component responsible for the Telegram Mini Apps viewport.

Mounting

Before using the component, it is necessary to mount it to work with properly configured properties. To do so, use the mount method. It will update the isMounted signal property.

ts
import { viewport } from '@telegram-apps/sdk';

if (viewport.mount.isAvailable()) {
  viewport.mount();
  viewport.isMounted(); // true
}
ts
import {
  mountViewport,
  isViewportMounted,
} from '@telegram-apps/sdk';

if (mountViewport.isAvailable()) {
  mountViewport();
  isViewportMounted(); // true
}

To unmount, use the unmount method:

ts
viewport.unmount();
viewport.isMounted(); // false
ts
import {
  unmountViewport,
  isViewportMounted,
} from '@telegram-apps/sdk';

unmountViewport();
isViewportMounted(); // false

Binding CSS Variables

To expose the viewport properties via CSS variables, use the bindCssVars method. The isCssVarsBound signal property is updated after the method is called.

This method optionally accepts a function that transforms the values width, height and stableHeight into CSS variable names. By default, values are converted to kebab case with the prefix --tg-viewport-.

ts
import { viewport } from '@telegram-apps/sdk';

if (viewport.bindCssVars.isAvailable()) {
  viewport.bindCssVars();
  // Creates CSS variables like:
  // --tg-viewport-height: 675px
  // --tg-viewport-width: 320px
  // --tg-viewport-stable-height: 675px

  viewport.bindCssVars(key => `--my-prefix-${key}`);
  // Creates CSS variables like:
  // --my-prefix-height: 675px
  // --my-prefix-width: 320px
  // --my-prefix-stableHeight: 675px

  viewport.isCssVarsBound(); // true
}
ts
import {
  bindViewportCssVars,
  isViewportCssVarsBound,
} from '@telegram-apps/sdk';

if (bindViewportCssVars.isAvailable()) {
  bindViewportCssVars();
  // Creates CSS variables like:
  // --tg-viewport-height: 675px
  // --tg-viewport-width: 320px
  // --tg-viewport-stable-height: 675px

  bindViewportCssVars(key => `--my-prefix-${key}`);
  // Creates CSS variables like:
  // --my-prefix-height: 675px
  // --my-prefix-width: 320px
  // --my-prefix-stableHeight: 675px

  isViewportCssVarsBound(); // true
}

Expanding

To expand the viewport, use the expand method.

ts
if (viewport.expand.isAvailable()) {
  viewport.expand();
}
ts
import { expandViewport } from '@telegram-apps/sdk';

if (expandViewport.isAvailable()) {
  expandViewport();
}

Released under the MIT License.