@capgo/capacitor-sheets

Framework-agnostic sheets, drawers, dialogs, scroll helpers, and overlay primitives for Capacitor apps.

This package is inspired by the public Silk feature surface, but it is not a wrapper around Silk and does not include Silk source code. It uses platform web APIs and custom elements so the same primitives work in React, Vue, Angular, Svelte, Solid, or plain TypeScript.

Usecase Demos

Each usecase has its own animated WebP demo. These match the public Silk-style example set: long sheets, detents, sidebars, bottom/top sheets, keyboard-aware sheets, toasts, detached sheets, full pages, stacking, depth, parallax, lightboxes, persistent detents, and cards.

Long Sheet	Sheet with Detent
Sidebar	Bottom Sheet
Sheet with Keyboard	Toast
Detached Sheet	Page from Bottom
Top Sheet	Sheet with Stacking
Sheet with Depth	Parallax Page
Page	Lightbox
Persistent Sheet with Detent	Card

Online Playgrounds

Each framework example opens the same 16-usecase gallery, so StackBlitz is useful for testing the full surface instead of a single smoke-test sheet:

• React playground
• Vue playground
• Angular playground
• Svelte playground
• Solid playground

Mobile Test App

The repo includes a Capacitor app that wraps the React gallery so the sheets can be tested on real iOS and Android devices. The app id is app.capgo.capacitor.sheets. Capacitor 8 requires Node.js 22 or newer for local mobile commands.

npm run build:mobile
npx cap run ios
npx cap run android

Capgo OTA uploads use the same built gallery:

npx @capgo/cli@latest app add app.capgo.capacitor.sheets --name "Capgo Sheets"
npm run deploy:capgo:dev
npm run deploy:capgo

Create the Capgo app once before the first upload. GitHub Actions also include a Capgo deploy workflow. Tag builds deploy to production, alpha tags deploy to dev, and manual runs can choose either channel. Set CAPGO_TOKEN in repository secrets before running it.

Features

• Framework agnostic custom elements: no React runtime dependency in the core package.
• Bottom sheets, side drawers, top sheets, and centered dialogs through content-placement.
• Detents with em, rem, dvh, lvh, svh, calc(), and other modern CSS lengths.
• Touch, pointer, wheel, and trackpad gestures with dismissal, overshoot, and trap controls.
• Modal behavior: focus trap, focus restore, Escape dismissal, outside-click dismissal, and inert outside content.
• Capacitor safe-area defaults using env(safe-area-inset-*) plus Capacitor SystemBars --safe-area-inset-* fallbacks.
• Keyboard-aware layout using visualViewport resize/scroll events and preventScroll focus behavior.
• Overlay compatibility through cap-island and cap-external-overlay.
• Stacking and outlet animation hooks for depth effects and coordinated page motion.
• Scroll primitives with progress/distance helpers.
• Theme color dimming for Capacitor WebViews and mobile browsers.
• Modern CSS defaults authored with em-based sizing, with no design-system lock-in.

Usecase Coverage

Usecase	Capgo Sheets pattern
Long Sheet	cap-sheet + cap-scroll or naturally scrolling cap-sheet-content
Sheet with Detent	detents="18em 32em" and stepTo() / cap-sheet-trigger action="step"
Sidebar	content-placement="left" or content-placement="right"
Bottom Sheet	default content-placement="bottom"
Sheet with Keyboard	visual viewport offset support via native-focus-scroll-prevention
Toast	inert-outside="false", close-on-outside-click="false", focus-trap="false"
Detached Sheet	rounded content with margins and cap-sheet-special-wrapper composition
Page from Bottom	full-height bottom sheet content
Top Sheet	content-placement="top"
Sheet with Stacking	cap-sheet-stack, stack depth variables, and stacking animation hooks
Sheet with Depth	cap-sheet-outlet progress variables and travelAnimation
Parallax Page	cap-sheet-outlet + cap-scroll progress composition
Page	full-viewport sheet content or side-entering content-placement
Lightbox	content-placement="center" plus backdrop and media content
Persistent Sheet with Detent	default-presented, swipe-dismissal="false", inert-outside="false", close-on-outside-click="false"
Card	content-placement="center" with compact content

Installation

npm install @capgo/capacitor-sheets
npx cap sync

Capacitor Setup

Add viewport-fit=cover so iOS exposes safe-area insets to CSS:

<meta name="viewport" content="width=device-width, initial-scale=1.0, viewport-fit=cover" />

Safe areas are enabled by default. cap-sheet-view reads standard env(safe-area-inset-*) values and Capacitor SystemBars fallback variables such as --safe-area-inset-bottom, then applies them to the sheet viewport in em-based layout. You can opt out or choose edges per sheet:

<cap-sheet safe-area="none"></cap-sheet>
<cap-sheet safe-area="bottom left right"></cap-sheet>

For Capacitor apps with overlay status/system bars, keep the platform plugins responsible for exposing correct insets:

import type { CapacitorConfig } from '@capacitor/cli';

const config: CapacitorConfig = {
  plugins: {
    StatusBar: {
      overlaysWebView: true,
    },
    Keyboard: {
      resize: 'body',
      resizeOnFullScreen: true,
    },
    SystemBars: {
      insetsHandling: 'css',
    },
  },
};

export default config;

Keyboard handling is on by default through native-focus-scroll-prevention. It listens to visualViewport changes, keeps focused controls visible above the keyboard, and restores the sheet offset when the keyboard closes.

Vanilla Usage

<script type="module">
  import '@capgo/capacitor-sheets';
</script>

<cap-sheet-trigger for="booking-sheet" action="present">Open</cap-sheet-trigger>

<cap-sheet id="booking-sheet" detents="18em 32em" content-placement="bottom">
  <cap-sheet-portal>
    <cap-sheet-view>
      <cap-sheet-backdrop></cap-sheet-backdrop>
      <cap-sheet-content class="sheet">
        <cap-sheet-bleeding-background></cap-sheet-bleeding-background>
        <cap-sheet-handle></cap-sheet-handle>
        <cap-sheet-title>Evening route</cap-sheet-title>
        <cap-sheet-description>Choose a route and confirm pickup.</cap-sheet-description>
        <cap-sheet-trigger action="dismiss">Done</cap-sheet-trigger>
      </cap-sheet-content>
    </cap-sheet-view>
  </cap-sheet-portal>
</cap-sheet>

.sheet {
  width: min(100%, 34em);
  padding: 0 1.25em 1.25em;
}

Five Framework Examples

Full runnable examples live in:

• examples/react-app
• examples/vue-app
• examples/angular-app
• examples/svelte-app
• examples/solid-app

All five apps mount the shared usecase gallery from examples/shared/usecase-gallery.ts. That gallery covers Long Sheet, Sheet with Detent, Sidebar, Bottom Sheet, Sheet with Keyboard, Toast, Detached Sheet, Page from Bottom, Top Sheet, Sheet with Stacking, Sheet with Depth, Parallax Page, Page, Lightbox, Persistent Sheet with Detent, and Card.

React

import { setupSheet } from '@capgo/capacitor-sheets/react';
import { useEffect, useRef } from 'react';
import '@capgo/capacitor-sheets';
import { mountUsecaseGallery } from '../../shared/usecase-gallery';

export function App() {
  const galleryRef = useRef<HTMLDivElement>(null);

  useEffect(() => {
    if (!galleryRef.current) return;
    return mountUsecaseGallery(galleryRef.current, {
      framework: 'React',
      setupSheet,
    });
  }, []);

  return <div ref={galleryRef} />;
}

Vue

<script setup lang="ts">
import { onMounted, onUnmounted, ref } from 'vue';
import { setupSheet } from '@capgo/capacitor-sheets/vue';
import '@capgo/capacitor-sheets';
import { mountUsecaseGallery } from '../../shared/usecase-gallery';

const galleryRef = ref<HTMLElement | null>(null);
let cleanup: (() => void) | undefined;

onMounted(() => {
  if (galleryRef.value) {
    cleanup = mountUsecaseGallery(galleryRef.value, {
      framework: 'Vue',
      setupSheet,
    });
  }
});

onUnmounted(() => cleanup?.());
</script>

<template>
  <div ref="galleryRef"></div>
</template>

Angular

import type { AfterViewInit, ElementRef, OnDestroy } from '@angular/core';
import { Component, CUSTOM_ELEMENTS_SCHEMA, ViewChild } from '@angular/core';
import { setupSheet } from '@capgo/capacitor-sheets/angular';
import '@capgo/capacitor-sheets';
import { mountUsecaseGallery } from '../../../shared/usecase-gallery';

@Component({
  selector: 'app-root',
  standalone: true,
  schemas: [CUSTOM_ELEMENTS_SCHEMA],
  template: `<div #gallery></div>`,
})
export class AppComponent implements AfterViewInit, OnDestroy {
  @ViewChild('gallery', { static: true }) gallery?: ElementRef<HTMLElement>;
  private cleanup?: () => void;

  ngAfterViewInit(): void {
    if (this.gallery?.nativeElement) {
      this.cleanup = mountUsecaseGallery(this.gallery.nativeElement, {
        framework: 'Angular',
        setupSheet,
      });
    }
  }

  ngOnDestroy(): void {
    this.cleanup?.();
  }
}

Svelte

<script lang="ts">
  import { onMount } from 'svelte'
  import { setupSheet } from '@capgo/capacitor-sheets/svelte'
  import '@capgo/capacitor-sheets'
  import { mountUsecaseGallery } from '../../shared/usecase-gallery'

  let gallery: HTMLDivElement

  onMount(() =>
    mountUsecaseGallery(gallery, {
      framework: 'Svelte',
      setupSheet,
    }),
  )
</script>

<div bind:this={gallery}></div>

Solid

import { onCleanup, onMount } from 'solid-js';
import { setupSheet } from '@capgo/capacitor-sheets/solid';
import '@capgo/capacitor-sheets';
import { mountUsecaseGallery } from '../../shared/usecase-gallery';

export function App() {
  let galleryEl!: HTMLDivElement;

  onMount(() => {
    const cleanup = mountUsecaseGallery(galleryEl, {
      framework: 'Solid',
      setupSheet,
    });
    onCleanup(cleanup);
  });

  return <div ref={galleryEl} />;
}

API Surface

Core elements:

• cap-sheet: state, detents, placement, gestures, modal behavior, lifecycle events.
• cap-sheet-trigger: declarative present, dismiss, toggle, and step actions.
• cap-sheet-portal: optional body portal for overlay layering.
• cap-sheet-view: viewport overlay host.
• cap-sheet-backdrop: progress-synced modal backdrop.
• cap-sheet-content: accessible sheet surface.
• cap-sheet-bleeding-background: background extension for rounded edge sheets.
• cap-sheet-handle: draggable and keyboard-accessible detent handle.
• cap-sheet-title and cap-sheet-description: accessible naming.
• cap-sheet-special-wrapper and cap-sheet-special-wrapper-content: composition hooks for detached sheets, cards, lightboxes, and custom page layouts.
• cap-sheet-stack: groups sheets for stacked depth.
• cap-sheet-outlet: receives sheet progress variables and optional travelAnimation.
• cap-scroll and cap-scroll-content: scroll progress helpers.
• cap-fixed, cap-island, cap-external-overlay, cap-visually-hidden, cap-auto-focus-target: composition and accessibility helpers.

Important events:

• cap-sheet-presented-change
• cap-sheet-active-detent-change
• cap-sheet-travel
• cap-sheet-travel-status-change
• cap-sheet-travel-range-change
• cap-sheet-drag-start
• cap-sheet-drag-end
• cap-scroll

Imperative methods on cap-sheet:

const sheet = document.querySelector('cap-sheet')!;
await sheet.present();
await sheet.dismiss();
await sheet.toggle();
await sheet.stepTo(2);
await sheet.step('down');

The public TypeScript API is documented with TSDoc in src/core/types.ts, and generated declarations are emitted during npm run build.

Development

npm install
npm run render:demos
npm run build
npm run dev:examples -- react vue svelte angular solid

In the Capgo monorepo, use bun and bunx for local commands.