add chrome.power/keep awake as an api sample

api-samples/power/README.md

@@ -0,0 +1,13 @@
+# chrome.power
+
+This extension demonstrates the `chrome.power` API by allowing users to override their system's power management features.
+
+## Overview
+
+The extension creates add a popup, that cycles different states when clicked. It will go though a mode that prevents the display from dimming or going to sleep, a mode that keeps the system awake but allows the screen to dim/go to sleep, and whatever the system's default is.
+
+## Running this extension
+
+1. Clone this repository.
+2. Load this directory in Chrome as an [unpacked extension](https://developer.chrome.com/docs/extensions/mv3/getstarted/development-basics/#load-unpacked).
+3. Pin the extension to the taskbar and click the action button.

api-samples/power/_locales/en/messages.json

@@ -0,0 +1,22 @@
+{
+  "extensionName": {
+    "message": "Keep Awake",
+    "description": "Extension name."
+  },
+  "extensionDescription": {
+    "message": "Override system power-saving settings.",
+    "description": "Extension description."
+  },
+  "disabledTitle": {
+    "message": "Default power-saving settings",
+    "description": "Browser action title when disabled."
+  },
+  "displayTitle": {
+    "message": "Screen will be kept on",
+    "description": "Browser action title when preventing screen-off."
+  },
+  "systemTitle": {
+    "message": "System will stay awake",
+    "description": "Browser action title when preventing system sleep."
+  }
+}

api-samples/power/background.js

@@ -0,0 +1,99 @@
+// Copyright (c) 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+/**
+ * States that the extension can be in.
+ */
+let StateEnum = {
+  DISABLED: 'disabled',
+  DISPLAY: 'display',
+  SYSTEM: 'system'
+};
+
+/**
+ * Key used for storing the current state in {localStorage}.
+ */
+let STATE_KEY = 'state';
+
+/**
+ * Loads the locally-saved state asynchronously.
+ * @param {function} callback Callback invoked with the loaded {StateEnum}.
+ */
+function loadSavedState(callback) {
+  chrome.storage.local.get(STATE_KEY, function (items) {
+    let savedState = items[STATE_KEY];
+    for (let key in StateEnum) {
+      if (savedState == StateEnum[key]) {
+        callback(savedState);
+        return;
+      }
+    }
+    callback(StateEnum.DISABLED);
+  });
+}
+
+/**
+ * Switches to a new state.
+ * @param {string} newState New {StateEnum} to use.
+ */
+function setState(newState) {
+  let imagePrefix = 'night';
+  let title = '';
+
+  switch (newState) {
+    case StateEnum.DISABLED:
+      chrome.power.releaseKeepAwake();
+      imagePrefix = 'night';
+      title = chrome.i18n.getMessage('disabledTitle');
+      break;
+    case StateEnum.DISPLAY:
+      chrome.power.requestKeepAwake('display');
+      imagePrefix = 'day';
+      title = chrome.i18n.getMessage('displayTitle');
+      break;
+    case StateEnum.SYSTEM:
+      chrome.power.requestKeepAwake('system');
+      imagePrefix = 'sunset';
+      title = chrome.i18n.getMessage('systemTitle');
+      break;
+    default:
+      throw 'Invalid state "' + newState + '"';
+  }
+
+  let items = {};
+  items[STATE_KEY] = newState;
+  chrome.storage.local.set(items);
+
+  chrome.action.setIcon({
+    path: {
+      19: 'images/' + imagePrefix + '-19.png',
+      38: 'images/' + imagePrefix + '-38.png'
+    }
+  });
+  chrome.action.setTitle({ title: title });
+}
+
+chrome.action.onClicked.addListener(function () {
+  loadSavedState(function (state) {
+    switch (state) {
+      case StateEnum.DISABLED:
+        setState(StateEnum.DISPLAY);
+        break;
+      case StateEnum.DISPLAY:
+        setState(StateEnum.SYSTEM);
+        break;
+      case StateEnum.SYSTEM:
+        setState(StateEnum.DISABLED);
+        break;
+      default:
+        throw 'Invalid state "' + state + '"';
+    }
+  });
+});
+
+chrome.runtime.onStartup.addListener(function () {
+  loadSavedState(function (state) {
+    setState(state);
+  });
+});

api-samples/power/manifest.json

@@ -0,0 +1,26 @@
+{
+  "manifest_version": 3,
+
+  "name": "__MSG_extensionName__",
+  "description": "__MSG_extensionDescription__",
+  "version": "1.9",
+  "icons": {
+    "16": "images/icon-16.png",
+    "48": "images/icon-48.png",
+    "128": "images/icon-128.png"
+  },
+
+  "permissions": ["power", "storage"],
+  "action": {
+    "default_title": "__MSG_disabledTitle__",
+    "default_icon": {
+      "19": "images/night-19.png",
+      "38": "images/night-38.png"
+    }
+  },
+  "background": {
+    "service_worker": "background.js"
+  },
+
+  "default_locale": "en"
+}