Add demo for Window Management API

README.md

@@ -5,11 +5,11 @@ Code examples that accompany various MDN DOM and Web API documentation pages.
 
 * The "audiocontext-setsinkid" directory contains an example of how to use the [`AudioContext.setSinkId()`](https://developer.mozilla.org/en-US/docs/Web/API/AudioContext/setSinkId) method and related features. [Run the example live](https://mdn.github.io/dom-examples/audiocontext-setsinkid/).
 
-* The "auxclick" directory contains a simple example demonstrating the new <code>auxclick</code> event type. See [GlobalEventHandlers.auxclick](https://developer.mozilla.org/en-US/docs/Web/API/GlobalEventHandlers/onauxclick) for more details, or [run the example live](https://mdn.github.io/dom-examples/auxclick/).
+* The "auxclick" directory contains a basic example demonstrating the new <code>auxclick</code> event type. See [GlobalEventHandlers.auxclick](https://developer.mozilla.org/en-US/docs/Web/API/GlobalEventHandlers/onauxclick) for more details, or [run the example live](https://mdn.github.io/dom-examples/auxclick/).
 
 * The "canvas" directory contains an example "chroma-keying" demonstrating how to use the Canvas API to manipulate videos: see [Manipulating video using canvas](https://developer.mozilla.org/en-US/docs/Web/API/Canvas_API/Manipulating_video_using_canvas) or [run the example live](https://mdn.github.io/dom-examples/canvas/chroma-keying/).
 
-* The "channel-messaging-basic" directory contains a simple example demonstrating the basics of channel messaging; see [Channel Messaging API](https://developer.mozilla.org/en-US/docs/Web/API/Channel_Messaging_API) or [run the example live](https://mdn.github.io/dom-examples/channel-messaging-basic/).
+* The "channel-messaging-basic" directory contains a basic example demonstrating the basics of channel messaging; see [Channel Messaging API](https://developer.mozilla.org/en-US/docs/Web/API/Channel_Messaging_API) or [run the example live](https://mdn.github.io/dom-examples/channel-messaging-basic/).
 
 * The "channel-messaging-multimessage" directory contains another channel messaging demo, showing how multiple messages can be sent between browsing contexts. See [Channel Messaging API](https://developer.mozilla.org/en-US/docs/Web/API/Channel_Messaging_API) for more details. [Run the demo live](https://mdn.github.io/dom-examples/channel-messaging-multimessage/).
 
@@ -21,48 +21,50 @@ Code examples that accompany various MDN DOM and Web API documentation pages.
 
 * The "indexeddb-api" directory contains a demo for the [IndexedDB API](https://mdn.github.io/dom-examples/indexeddb-api/index.html).
 
-* The "insert-adjacent" directory contains simple demos for [insertAdjacentElement](https://mdn.github.io/dom-examples/insert-adjacent/insertAdjacentElement.html) and [insertAdjacentText](https://mdn.github.io/dom-examples/insert-adjacent/insertAdjacentText.html).
+* The "insert-adjacent" directory contains basic demos for [insertAdjacentElement](https://mdn.github.io/dom-examples/insert-adjacent/insertAdjacentElement.html) and [insertAdjacentText](https://mdn.github.io/dom-examples/insert-adjacent/insertAdjacentText.html).
 
-* The "matchmedia" directory contains a simple demo to test matchMedia functionality. See [Window.matchMedia](https://developer.mozilla.org/en-US/docs/Web/API/Window/matchMedia) for more details. [Run the demo live](https://mdn.github.io/dom-examples/matchmedia/).
+* The "matchmedia" directory contains a basic demo to test matchMedia functionality. See [Window.matchMedia](https://developer.mozilla.org/en-US/docs/Web/API/Window/matchMedia) for more details. [Run the demo live](https://mdn.github.io/dom-examples/matchmedia/).
 
-* The "mediaquerylist" directory contains a simple demo to test more advanced matchMedia/mediaquerylist functionality. See [MediaQueryList](https://developer.mozilla.org/en-US/docs/Web/API/MediaQueryList) for more details. [Run the demo live](https://mdn.github.io/dom-examples/mediaquerylist/index.html).
+* The "mediaquerylist" directory contains a basic demo to test more advanced matchMedia/mediaquerylist functionality. See [MediaQueryList](https://developer.mozilla.org/en-US/docs/Web/API/MediaQueryList) for more details. [Run the demo live](https://mdn.github.io/dom-examples/mediaquerylist/index.html).
 
 * The "media" directory contains examples and demos showing how to use HTML and DOM [media elements and APIs](https://developer.mozilla.org/en-US/docs/Web/Media).
 
 * The "payment-request" directory contains examples of the [Payment Request API](https://developer.mozilla.org/en-US/docs/Web/API/Payment_Request_API).
 
 * The "pointerevents" directory is for examples and demos of the [Pointer Events](https://developer.mozilla.org/en-US/docs/Web/API/Pointer_events) standard.
 
-* The "pointer-lock" directory contains a simple demo to show usage of the Pointer Lock API. You can find more explanation of how the demo works at the main MDN [Pointer Lock API](https://developer.mozilla.org/en-US/docs/Web/API/Pointer_Lock_API) page. [Run the demo live](https://mdn.github.io/dom-examples/pointer-lock/).
+* The "pointer-lock" directory contains a basic demo to show usage of the Pointer Lock API. You can find more explanation of how the demo works at the main MDN [Pointer Lock API](https://developer.mozilla.org/en-US/docs/Web/API/Pointer_Lock_API) page. [Run the demo live](https://mdn.github.io/dom-examples/pointer-lock/).
 
 * The "popover-api" directory is for examples and demos of the [Popover API](https://developer.mozilla.org/en-US/docs/Web/API/Popover_API) standard. Go to the [Popover API demo index](popover-api/) to see what's available.
 
-* The "reporting-api" directory contains a couple of simple demos to show usage of the Reprting API. You can find more explanation of how the API works in the main MDN [Reporting API](https://developer.mozilla.org/en-US/docs/Web/API/Reporting_API) docs. [Run the deprecation report demo live](https://mdn.github.io/dom-examples/reporting-api/deprecation_report.html).
+* The "reporting-api" directory contains a couple of basic demos to show usage of the Reprting API. You can find more explanation of how the API works in the main MDN [Reporting API](https://developer.mozilla.org/en-US/docs/Web/API/Reporting_API) docs. [Run the deprecation report demo live](https://mdn.github.io/dom-examples/reporting-api/deprecation_report.html).
 
-* The "resize-event" directory contains a simple demo to show how you can use the [resize event](https://developer.mozilla.org/en-US/docs/Web/API/Window/resize_event). Resize the browser window either by height or width to see the size of your current window. [Run the demo live](https://mdn.github.io/dom-examples/resize-event).
+* The "resize-event" directory contains a basic demo to show how you can use the [resize event](https://developer.mozilla.org/en-US/docs/Web/API/Window/resize_event). Resize the browser window either by height or width to see the size of your current window. [Run the demo live](https://mdn.github.io/dom-examples/resize-event).
 
 * The "screenleft-screentop" directory contains a demo to show how you could use the [Window.screenLeft](https://developer.mozilla.org/en-US/docs/Web/API/Window/screenLeft) and [Window.screenTop](https://developer.mozilla.org/en-US/docs/Web/API/Window/screenTop) properties to draw a circle on a canvas that always stays in the same physical place on the screen when you move your browser window. [Run the demo live](https://mdn.github.io/dom-examples/screenleft-screentop/).
 
 * The "scrolltooptions" directory contains a demo to show how you could use the [ScrollToOptions](https://developer.mozilla.org/en-US/docs/Web/API/ScrollToOptions) dictionary along with the [Window.ScrollTo()](https://developer.mozilla.org/en-US/docs/Web/API/Window/scrollTo) method to programmatically scroll a web page. [Run the demo live](https://mdn.github.io/dom-examples/scrolltooptions/).
 
-* The "server-sent-events" directory contains a very simple SSE demo that uses PHP to create the server. You can find more information in our [Using server-sent events](https://developer.mozilla.org/en-US/docs/Web/API/Server-sent_events/Using_server-sent_events) article. To run the demo you'll need to serve the files from a server that supports PHP; [MAMP](https://www.mamp.info/en/) is a good PHP test server environment.
+* The "server-sent-events" directory contains a very basic SSE demo that uses PHP to create the server. You can find more information in our [Using server-sent events](https://developer.mozilla.org/en-US/docs/Web/API/Server-sent_events/Using_server-sent_events) article. To run the demo you'll need to serve the files from a server that supports PHP; [MAMP](https://www.mamp.info/en/) is a good PHP test server environment.
 
 * The "streams" directory contains demos of the Streams API for using low-level I/O processing.
 
 * The "touchevents" directory is for examples and demos of the [Touch Events](https://developer.mozilla.org/en-US/docs/Web/API/Touch_events) standard.
 
 * The "web-animations-api" directory contains [Web Animation API](https://developer.mozilla.org/en-US/docs/Web/API/Web_Animations_API) demos. See the [web animations README](web-animations-api/README.md) for more information.
 
-* The "web-storage" directory contains a simple demo to show usage of the Web Storage API. For more detail on how it works, read [Using the Web Storage API](https://developer.mozilla.org/en-US/docs/Web/API/Web_Storage_API/Using_the_Web_Storage_API). [View the demo live](https://mdn.github.io/dom-examples/web-storage/).
+* The "web-storage" directory contains a basic demo to show usage of the Web Storage API. For more detail on how it works, read [Using the Web Storage API](https://developer.mozilla.org/en-US/docs/Web/API/Web_Storage_API/Using_the_Web_Storage_API). [View the demo live](https://mdn.github.io/dom-examples/web-storage/).
 
-* The "view-transitions" directory contains a simple demo to show usage of the [View Transitions API](https://developer.mozilla.org/en-US/docs/Web/API/View_Transitions_API). [View the demo live](https://mdn.github.io/dom-examples/view-transitions/).
+* The "view-transitions" directory contains a basic demo to show usage of the [View Transitions API](https://developer.mozilla.org/en-US/docs/Web/API/View_Transitions_API). [View the demo live](https://mdn.github.io/dom-examples/view-transitions/).
 
-* The "web-share" directory contains a simple demo to show usage of the [Web Share API](https://developer.mozilla.org/en-US/docs/Web/API/Navigator/share). [View the demo live](https://mdn.github.io/dom-examples/web-share/).
+* The "web-share" directory contains a basic demo to show usage of the [Web Share API](https://developer.mozilla.org/en-US/docs/Web/API/Navigator/share). [View the demo live](https://mdn.github.io/dom-examples/web-share/).
 
-* The "web-workers" directory contains a simple web worker to demonstrate how [Web Workers](https://developer.mozilla.org/en-US/docs/Web/API/Web_Workers_API) work. [View the demo live](https://mdn.github.io/dom-examples/web-workers/simple-web-worker/).
+* The "web-workers" directory contains a basic web worker to demonstrate how [Web Workers](https://developer.mozilla.org/en-US/docs/Web/API/Web_Workers_API) work. [View the demo live](https://mdn.github.io/dom-examples/web-workers/simple-web-worker/).
 
 * The ["webgl-examples"](webgl-examples/README.md) directory contains a number of WebGL examples that demonstrate the [WebGL API](https://developer.mozilla.org/en-US/docs/Web/API/WebGL_API), which is used for 2D and 3D graphics on the web.
 
 * The "webgpu-compute-demo" directory contains an example that demonstrates basic usage of the [WebGPU API](https://developer.mozilla.org/en-US/docs/Web/API/WebGPU_API) compute pipeline, which is used for performing general computation on the GPU. [View the demo live](https://mdn.github.io/dom-examples/webgpu-compute-demo/).
 
-* The "webgpu-render-demo" directory contains an example that demonstrates basic usage of the [WebGPU API](https://developer.mozilla.org/en-US/docs/Web/API/WebGPU_API) render pipeline, which is used for rendering high-performance graphics via the GPU. [View the demo live](https://mdn.github.io/dom-examples/webgpu-render-demo/).
+* The "webgpu-render-demo" directory contains an example that demonstrates basic usage of the [WebGPU API](https://developer.mozilla.org/en-US/docs/Web/API/WebGPU_API) render pipeline, which is used for rendering high-performance graphics via the GPU. [View the demo live](https://mdn.github.io/dom-examples/webgpu-render-demo/).
+
+* The "window-management-api" directory contains a basic demo to show usage of the [Window Management API](https://developer.mozilla.org/en-US/docs/Web/API/Window_Management_API). [View the demo live](https://mdn.github.io/dom-examples/window-management-api/).

window-management-api/index.css

@@ -0,0 +1,21 @@
+html {
+  font-family: Arial, Helvetica, sans-serif;
+  font-size: 1.1rem;
+}
+
+body {
+  width: 70%;
+  max-width: 800px;
+  margin: 0 auto;
+}
+
+p,
+li {
+  letter-spacing: 0.5px;
+  line-height: 1.5;
+}
+
+hr {
+  color: gray;
+  border-width: 3px;
+}

window-management-api/index.html

@@ -0,0 +1,33 @@
+<!doctype html>
+<html lang="en">
+
+<head>
+  <meta charset="utf-8">
+  <title>Window Management API demo</title>
+
+  <link href="index.css" rel="stylesheet">
+  <script defer src="index.js"></script>
+</head>
+
+<body>
+  <h1>Window Management API demo</h1>
+
+  <p>This page provides a basic demo of the <a
+      href="https://developer.mozilla.org/en-US/docs/Web/API/Window_Management_API">Window Management API</a>, which in
+    <a href="https://developer.mozilla.org/en-US/docs/Web/API/Window_Management_API#browser_compatibility">supporting
+      browsers</a> provides a button to open multiple windows to provide an HTML, CSS, and JavaScript learning
+    environment, tailored to whether you have one, two, or more screens available.
+  </p>
+
+  <p>On non-supporting browsers it will provide links to the different windows instead, so users of those browsers can
+    have access to that content, and can choose to arrange the opened pages in new tabs or windows as they see fit.</p>
+
+  <hr>
+
+  <section>
+
+
+  </section>
+</body>
+
+</html>

window-management-api/index.js

@@ -0,0 +1,190 @@
+// Data for the sites to open
+const sites = [
+  {
+    "name": "MDN code playground",
+    "url": "https://developer.mozilla.org/en-US/play"
+  },
+  {
+    "name": "MDN HTML reference",
+    "url": "https://developer.mozilla.org/en-US/docs/Web/HTML"
+  },
+  {
+    "name": "MDN CSS reference",
+    "url": "https://developer.mozilla.org/en-US/docs/Web/CSS"
+  },
+  {
+    "name": "MDN JavaScript reference",
+    "url": "https://developer.mozilla.org/en-US/docs/Web/JavaScript"
+  }
+]
+
+const outputElem = document.querySelector("section");
+
+// Array to hold references to the currently open windows
+let windowRefs = [];
+
+// Constants to represent the width and height of the Chrome UI when calculating the window size to open 
+const WINDOW_CHROME_Y = 51;
+const WINDOW_CHROME_X = 1;
+
+// Feature detection: we'll open windows in sites that support the API
+// and create links in sites that do not
+if ("getScreenDetails" in window) {
+  // The Window Management API is supported
+  createButton();
+} else {
+  // The Window Management API is not supported
+  createLinks(sites);
+}
+
+// Functions for creating the links or the button
+
+function createLinks(sites) {
+  const list = document.createElement("ul");
+
+  sites.forEach(site => {
+    const listItem = document.createElement("li");
+    const link = document.createElement("a");
+
+    link.textContent = site.name;
+    link.href = site.url;
+
+    listItem.appendChild(link);
+    list.appendChild(listItem);
+  });
+
+  outputElem.appendChild(list);
+}
+
+function createButton() {
+  const btn = document.createElement("button");
+  btn.textContent = "Open learning environment"
+  outputElem.appendChild(btn);
+
+  btn.addEventListener("click", openWindows);
+}
+
+// Functions for creating the windows
+
+function openWindow(left, top, width, height, url) {
+  const windowFeatures = `left=${left},top=${top},width=${width},height=${height}`;
+  const windowRef = window.open(
+    url,
+    "_blank", // needed for it to open in a new window
+    windowFeatures,
+  );
+
+  // Store a reference to the window in the windowRefs array
+  windowRefs.push(windowRef);
+
+}
+
+function closeAllWindows() {
+  // Loop through all window refs and close each one 
+  windowRefs.forEach(windowRef => {
+    windowRef.close();
+  });
+  windowRefs = [];
+}
+
+async function openWindows() {
+  const screenDetails = await window.getScreenDetails();
+
+  // Return the number of screens
+  const noOfScreens = screenDetails.screens.length;
+
+  if (noOfScreens === 1) {
+    // Only one screen
+    const screen1 = screenDetails.screens[0];
+    // Windows will be half the width and half the height of the screen
+    let windowWidth = Math.floor((screen1.availWidth - 2 * WINDOW_CHROME_X) / 2);
+    let windowHeight = Math.floor((screen1.availHeight - 2 * WINDOW_CHROME_Y) / 2);
+
+    openWindow(screen1.availLeft,
+      screen1.availTop,
+      windowWidth,
+      windowHeight,
+      sites[0].url);
+    openWindow(windowWidth + screen1.availLeft + WINDOW_CHROME_X,
+      screen1.availTop,
+      windowWidth,
+      windowHeight,
+      sites[1].url);
+    openWindow(screen1.availLeft,
+      windowHeight + screen1.availHeight + WINDOW_CHROME_Y,
+      windowWidth,
+      windowHeight,
+      sites[2].url);
+    openWindow(windowWidth + screen1.availLeft + WINDOW_CHROME_X,
+      windowHeight + screen1.availHeight + WINDOW_CHROME_Y,
+      windowWidth,
+      windowHeight,
+      sites[3].url);
+
+  } else {
+    // Two screens or more
+    const screen1 = screenDetails.screens[0];
+    const screen2 = screenDetails.screens[1];
+    // Windows will be a third the width and the full height of the screen
+    let windowWidth = Math.floor((screen1.availWidth - 3 * WINDOW_CHROME_X) / 3);
+    let windowHeight = Math.floor(screen1.availHeight - WINDOW_CHROME_Y);
+
+    // Open the reference windows in thirds across the entire height of the primary screen
+    openWindow(screen1.availLeft,
+      screen1.availTop,
+      windowWidth,
+      windowHeight,
+      sites[1].url);
+    openWindow(screen1.availLeft + windowWidth + WINDOW_CHROME_X,
+      screen1.availTop,
+      windowWidth,
+      windowHeight,
+      sites[2].url);
+    openWindow(screen1.availLeft + ((windowWidth + WINDOW_CHROME_X) * 2),
+      screen1.availTop,
+      windowWidth,
+      windowHeight,
+      sites[3].url);
+
+    // Open the code editor the full size of the secondary screen
+    openWindow(screen2.availLeft,
+      screen2.availTop,
+      screen2.availWidth,
+      screen2.availHeight,
+      sites[0].url);
+  }
+
+  // Check whether one of our popup windows has been closed
+  // If so, close them all
+
+  closeMonitor = setInterval(checkWindowClose, 250);
+
+  function checkWindowClose() {
+    if (windowRefs.some(windowRef => windowRef.closed)) {
+      closeAllWindows();
+      clearInterval(closeMonitor);
+    }
+  }
+
+  // Also close our popup windows if the main app window is closed
+
+  window.addEventListener("beforeunload", () => {
+    closeAllWindows();
+  });
+
+  screenDetails.addEventListener("screenschange", () => {
+    // If the new number of screens is different to the old number of screens, report the difference
+    if (screenDetails.screens.length !== noOfScreens) {
+      console.log(
+        `The screen count changed from ${noOfScreens} to ${screenDetails.screens.length}`,
+      );
+    }
+
+    // If the windows are open, close them and then open them again
+    // So that they fit with the new screen configuration
+    if (windowRefs.length > 0) {
+      closeAllWindows();
+      openWindows();
+    }
+  });
+}