Add example extension using Font Settings API.

chrome/common/extensions/docs/examples/api/fontSettings/popup.js

+// Copyright (c) 2012 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.
+
+var scriptList;
+
+// Mapping between font list ids and the generic family setting they
+// represent.
+var genericFamilies = [
+  { fontList: 'standardFontList', name: 'standard' },
+  { fontList: 'serifFontList', name: 'serif' },
+  { fontList: 'sansSerifFontList', name: 'sansserif' },
+  { fontList: 'fixedFontList', name: 'fixed' }
+];
+
+function getSelectedScript() {
+  return scriptList.options[scriptList.selectedIndex].value;
+}
+
+function getSelectedFont(fontList) {
+  return fontList.options[fontList.selectedIndex].value;
+}
+
+// Populates the font lists with the list of system fonts from |fonts|.
+function populateLists(fonts) {
+  for (var i = 0; i < genericFamilies.length; i++) {
+    var list = document.getElementById(genericFamilies[i].fontList);
+
+    // Add special "(none)" item to indicate fallback to the non-per-script
+    // font setting. The Font Settings API uses the empty string to indicate
+    // fallback.
+    var noneItem = document.createElement('option');
+    noneItem.value = '';
+    noneItem.text = '(none)';
+    list.add(noneItem);
+
+    for (var j = 0; j < fonts.length; j++) {
+      var item = document.createElement('option');
+      item.value = fonts[j].fontName;
+      item.text = fonts[j].localizedName;
+      list.add(item);
+    }
+  }
+
+  updateListSelections();
+}
+
+// Returns a function that updates the font setting for |genericFamily|
+// to match the selected value in |fontList|. It can be used as an event
+// handler for selection changes in |fontList|.
+function getFontChangeHandler(fontList, genericFamily) {
+  return function() {
+    var script = getSelectedScript();
+    var font = getSelectedFont(fontList);
+
+    chrome.experimental.fontSettings.setFontName({
+      script: script,
+      genericFamily: genericFamily,
+      fontName: font
+    });
+  };
+}
+
+// Sets the selected value of |fontList| to |fontName|.
+function setSelectedFont(fontList, fontName) {
+  var script = getSelectedScript();
+
+  for (var i = 0; i < fontList.length; i++) {
+    if (fontName == fontList.options[i].value) {
+      fontList.selectedIndex = i;
+      break;
+    }
+  }
+  if (i == fontList.length) {
+    console.warn("font '" + fontName + "' for " + fontList.id + ' for ' +
+        script + ' is not on the system');
+  }
+}
+
+// Returns a callback function that sets the selected value of |list| to the
+// font returned from |chrome.experimental.fontSettings.getFontName|.
+function getFontNameHandler(list) {
+  return function(details) {
+    setSelectedFont(list, details.fontName);
+  };
+}
+
+// Sets the selected value of each font list to the current font setting.
+function updateListSelections() {
+  var script = getSelectedScript();
+
+  for (var i = 0; i < genericFamilies.length; i++) {
+    var list = document.getElementById(genericFamilies[i].fontList);
+    var family = genericFamilies[i].name;
+
+    chrome.experimental.fontSettings.getFontName({
+      genericFamily: family,
+      script: script
+    }, getFontNameHandler(list));
+  }
+}
+
+function init() {
+  scriptList = document.getElementById('scriptList');
+  scriptList.addEventListener('change', updateListSelections);
+
+  // Populate the font lists.
+  chrome.experimental.fontSettings.getFontList(populateLists);
+
+  // Add change handlers to the font lists.
+  for (var i = 0; i < genericFamilies.length; i++) {
+    var list = document.getElementById(genericFamilies[i].fontList);
+    var handler = getFontChangeHandler(list, genericFamilies[i].name);
+    list.addEventListener('change', handler);
+  }
+}
+
+document.addEventListener('DOMContentLoaded', init);