How this sample is created

Create a polymer project
```
polymer init polymer-3-starter-kit
```

Add dwt library reference and global variables in index.html

<script src="https://unpkg.com/dwt@16.2.4/dist/dynamsoft.webtwain.min.js"></script>
<script type="text/javascript">
var DWObject;
window.onload = function () {
    Dynamsoft.WebTwainEnv.ProductKey = 't00921wAAAFYTYbgeiIdPK/NgJGUa+hoxpIV23O5q0c3iJmgz9SNsUIdL+FXtlfepBdbdSwiOHFSHPHA8y+SbtM5LGx2Bq+HeJUMV3kCdQNkBuiQoux/EPZaxC1UGK3k=';
    Dynamsoft.WebTwainEnv.ResourcesPath = 'https://unpkg.com/dwt@16.2.4/dist/';
};
</script>

Modify src/my-app.js

from

<a name="view1" href="[[rootPath]]view1">View One</a>

<a name="view1" href="[[rootPath]]view1">Scan Documents</a>

Modify my-view1.js

Add functions

ready(){
    super.ready();
    this.showDWT();
}
showDWT() {
    Dynamsoft.WebTwainEnv.CreateDWTObjectEx({ WebTwainId: 'shadowDom' }, (obj) => {
    this.shadowRoot.querySelector('#showDWT').style.display = "none";
    this.shadowRoot.querySelector('#scanbtn').style.display = "";
    DWObject = obj;
    DWObject.Viewer.bind(this.shadowRoot.querySelector('#dwtcontrolContainer'));
    DWObject.Viewer.width = 560;
    DWObject.Viewer.height = 600;
    DWObject.Viewer.show();
    }, function (e) {
    console.log(e)
    });
}
handleClick() {
    if (DWObject) {
    DWObject.SelectSource(function () {
        DWObject.AcquireImage(function () {

        }, function (err) { console.log(err); });
    }, function (err) { console.log(err); });
    }
}

Change HTML

from

<div class="card">
    <div class="circle">1</div>
    <h1>View One</h1>
    <p>Ut labores minimum atomorum pro. Laudem tibique ut has.</p>
    <p>Lorem ipsum dolor sit amet, per in nusquam nominavi periculis, sit elit oportere ea.Lorem ipsum dolor sit amet, per in nusquam nominavi periculis, sit elit oportere ea.Cu mei vide viris gloriatur, at populo eripuit sit.</p>
</div>

<div class="card">
    <div class="circle">1</div>
    <h1>Use Dynamic Web TWAIN to Scan</h1>
    <div id="dwtcontrolContainer"></div>
    <button id="showDWT" on-click="showDWT">Start</button>
    <button id="scanbtn" on-click="handleClick" style="display:none">scan</button>
</div>

------The following is the original readme from the polymer template------

Polymer App Toolbox - Starter Kit

This template is a starting point for building apps using a drawer-based layout. The layout is provided by app-layout elements.

This template, along with the polymer-cli toolchain, also demonstrates use of the "PRPL pattern" This pattern allows fast first delivery and interaction with the content at the initial route requested by the user, along with fast subsequent navigation by pre-caching the remaining components required by the app and progressively loading them on-demand as the user navigates through the app.

The PRPL pattern, in a nutshell:

Push components required for the initial route
Render initial route ASAP
Pre-cache components for remaining routes
Lazy-load and progressively upgrade next routes on-demand

Setup

Prerequisites

Install Polymer CLI using npm (we assume you have pre-installed node.js).

npm install -g polymer-cli@next

Initialize project from template

mkdir my-app
cd my-app
polymer init polymer-3-starter-kit

Start the development server

This command serves the app at http://127.0.0.1:8081 and provides basic URL routing for the app:

npm start

Build

The npm run build command builds your Polymer application for production, using build configuration options provided by the command line or in your project's polymer.json file.

You can configure your polymer.json file to create multiple builds. This is necessary if you will be serving different builds optimized for different browsers. You can define your own named builds, or use presets. See the documentation on building your project for production for more information.

The Polymer Starter Kit is configured to create three builds. These builds will be output to a subdirectory under the build/ directory as follows:

build/
  es5-bundled/
  es6-bundled/
  esm-bundled/

es5-bundled is a bundled, minified build with a service worker. ES6 code is compiled to ES5 for compatibility with older browsers.
es6-bundled is a bundled, minified build with a service worker. ES6 code is served as-is. This build is for browsers that can handle ES6 code - see building your project for production for a list.
esm-bundled is a bundled, minified build with a service worker. It uses standard ES module import/export statements for browsers that support them.

Run polymer help build for the full list of available options and optimizations. Also, see the documentation on the polymer.json specification and building your Polymer application for production.

Preview the build

This command serves your app. Replace build-folder-name with the folder name of the build you want to serve.

npm start build/build-folder-name/

Run tests

This command will run Web Component Tester against the browsers currently installed on your machine:

npm test

If running Windows you will need to set the following environment variables:

LAUNCHPAD_BROWSERS
LAUNCHPAD_CHROME

dynamsoft-dwt/dwt-polymer-simple