Added to options page to let users change keyboard mappings.

chrome/browser/resources/chromeos/switch_access/keyboard_handler.js

 // Copyright 2017 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.
 
-// TODO(elichtenberg): Move into custom logger class or somewhere else.
-let debuggingEnabled = true;
-
 /**
  * Class to handle keyboard input.
  *
  * @constructor
  * @param {SwitchAccessInterface} switchAccess
  */
 function KeyboardHandler(switchAccess) {
   /**
    * SwitchAccess reference.
+   *
    * @private {SwitchAccessInterface}
    */
   this.switchAccess_ = switchAccess;
 
   this.init_();
 }
 
 KeyboardHandler.prototype = {
   /**
    * Set up key listener.
    *
    * @private
    */
   init_: function() {
-    // Capture keycodes for keys 1 through 4, and 6 through 9.
-    let keyCodes =
-        ['1', '2', '3', '4', '6', '7', '8', '9'].map(key => key.charCodeAt(0));
-    chrome.accessibilityPrivate.setSwitchAccessKeys(keyCodes);
+    this.updateSwitchAccessKeys();
     document.addEventListener('keyup', this.handleKeyEvent_.bind(this));
   },
 
   /**
-   * Handle a keyboard event by calling the appropriate SwitchAccess functions.
+   * Update the keyboard keys captured by Switch Access to those stored in
+   * prefs.
+   */
+  updateSwitchAccessKeys: function() {
+    let keyCodes = [];
+    for (let command of this.switchAccess_.getCommands()) {
+      let keyCode = this.keyCodeFor_(command);
+      if ((keyCode >= '0'.charCodeAt(0) && keyCode <= '9'.charCodeAt(0)) ||
+          (keyCode >= 'A'.charCodeAt(0) && keyCode <= 'Z'.charCodeAt(0)))
+        keyCodes.push(keyCode);
+    }
+    chrome.accessibilityPrivate.setSwitchAccessKeys(keyCodes);
+  },
+
+  /**
+   * Return the key code that |command| maps to.
+   *
+   * @param {string} command
+   * @return {number}
+   */
+  keyCodeFor_: function(command) {
+    return this.switchAccess_.getNumberPref(command);
+  },
+
+  /**
+   * Run the command associated with the passed keyboard event.
    *
    * @param {!Event} event
    * @private
    */
   handleKeyEvent_: function(event) {
-    switch (event.key) {
-      case '1':
-        console.log('1 = go to next element');
-        this.switchAccess_.moveToNode(true);
-        break;
-      case '2':
-        console.log('2 = go to previous element');
-        this.switchAccess_.moveToNode(false);
-        break;
-      case '3':
-        console.log('3 = select element');
-        this.switchAccess_.selectCurrentNode();
-        break;
-      case '4':
-        this.switchAccess_.showOptionsPage();
-        break;
-    }
-    if (debuggingEnabled) {
-      switch (event.key) {
-        case '6':
-          console.log('6 = go to next element (debug mode)');
-          this.switchAccess_.debugMoveToNext();
-          break;
-        case '7':
-          console.log('7 = go to previous element (debug mode)');
-          this.switchAccess_.debugMoveToPrevious();
-          break;
-        case '8':
-          console.log('8 = go to child element (debug mode)');
-          this.switchAccess_.debugMoveToFirstChild();
-          break;
-        case '9':
-          console.log('9 = go to parent element (debug mode)');
-          this.switchAccess_.debugMoveToParent();
-          break;
+    for (let command of this.switchAccess_.getCommands()) {
+      if (this.keyCodeFor_(command) === event.keyCode) {
+        let key = event.key.toUpperCase();
+        console.log('\'' + key + '\' pressed for command: ' + command);
+        this.switchAccess_.runCommand(command);
+        this.switchAccess_.performedUserAction();
+        return;
       }
     }
-    this.switchAccess_.performedUserAction();
-  }
+  },
 };