为程序制作辅助功能是很重要的。在这里，我们很高兴地向你们介绍Devtron和Spectron。这两个新功能有机会使开发者们让他们的应用程序更加可用。

Electron 应用中有关辅助功能的开发和网站是相似的，因为两者最终使用的都是HTML. 然而, 对于Electron应用, 你不能使用在线的辅助功能审查者, 因为你的应用没有一个URL可以提供给审查者.

然而这些新功能将这些审查工具带到您的Electron应用中。您可以选择使用 Spectron 将审核添加到您的测试中, 或者在 DevTools 中使用 Devtron。 详见各工具的文档.

Accessibility

Making accessible applications is important and we're happy to introduce new functionality to Devtron and Spectron that gives developers the opportunity to make their apps better for everyone.

Accessibility concerns in Electron applications are similar to those of websites because they're both ultimately HTML. With Electron apps, however, you can't use the online resources for accessibility audits because your app doesn't have a URL to point the auditor to.

These new features bring those auditing tools to your Electron app. You can choose to add audits to your tests with Spectron or use them within DevTools with Devtron. Read on for a summary of the tools.

Spectron

在测试框架Spectron中，你可以审查应用程序中的每个window和<webview>标签。例如：

app.client.auditAccessibility().then(function (audit) {
  if (audit.failed) {
    console.error(audit.message)
  }
})

你可以从这里Spectron文档阅读到更多有关于这个功能的信息。

Spectron

In the testing framework Spectron, you can now audit each window and <webview> tag in your application. For example:

app.client.auditAccessibility().then(function (audit) {
  if (audit.failed) {
    console.error(audit.message)
  }
})

You can read more about this feature in Spectron's documentation.

Devtron

在 Devtron 中, 有一个新的辅助功能选项卡, 允许您对应用程序中的某一个页面进行审核, 并对审核结果进行排序和筛选。

这两种工具都使用了Google 为 Chrome 所构建的 辅助功能开发工具 库。 您可以在 repository's wiki 上了解到更加详细的辅助功能审核规则。

如果你知道其他适用于Electron的辅助功能开发工具, 请通过pull request添加到本文档中.

Devtron

In Devtron, there is a new accessibility tab which will allow you to audit a page in your app, sort and filter the results.

Both of these tools are using the Accessibility Developer Tools library built by Google for Chrome. You can learn more about the accessibility audit rules this library uses on that repository's wiki.

If you know of other great accessibility tools for Electron, add them to the accessibility documentation with a pull request.

启用辅助功能

由于性能原因, Electron应用程序在默认情况下禁用了辅助功能, 不过你可以通过多种方法启用它们。

Enabling Accessibility

Electron applications keep accessibility disabled by default for performance reasons but there are multiple ways to enable it.

应用程序内部

通过使用 app.setAccessibilitySupportEnabled(enabled), 可以在应用程序首选项中向用户开放辅助功能的开关。 用户的系统的辅助实用程序优先于此设置, 并将覆盖它。

Inside Application

By using app.setAccessibilitySupportEnabled(enabled), you can expose accessibility switch to users in the application preferences. User's system assistive utilities have priority over this setting and will override it.

辅助功能技术

Electron应用在检测到辅助功能技术(Windows) 或VoiceOver(macOS) 时会自动启用辅助功能 有关详细信息, 请参阅 Chrome 的 辅助功能文档 。

在 macOS 上, 在Electron应用中，可以通过 AXManualAccessibility来切换第三方的辅助功能：

CFStringRef kAXManualAccessibility = CFSTR("AXManualAccessibility");
+ (void)enableAccessibility:(BOOL)enable inElectronApplication:(NSRunningApplication *)app
{
    AXUIElementRef appRef = AXUIElementCreateApplication(app.processIdentifier);
    if (appRef == nil)  return;
    CFBooleanRef value = enable ? kCFBooleanTrue : kCFBooleanFalse;
    AXUIElementSetAttributeValue(appRef, kAXManualAccessibility, value);
    CFRelease(appRef);
}

Assistive Technology

Electron application will enable accessibility automatically when it detects assistive technology (Windows) or VoiceOver (macOS). See Chrome's accessibility documentation for more details.

On macOS, third-party assistive technology can switch accessibility inside Electron applications by setting the attribute AXManualAccessibility programmatically:

CFStringRef kAXManualAccessibility = CFSTR("AXManualAccessibility");
+ (void)enableAccessibility:(BOOL)enable inElectronApplication:(NSRunningApplication *)app
{
    AXUIElementRef appRef = AXUIElementCreateApplication(app.processIdentifier);
    if (appRef == nil)  return;
    CFBooleanRef value = enable ? kCFBooleanTrue : kCFBooleanFalse;
    AXUIElementSetAttributeValue(appRef, kAXManualAccessibility, value);
    CFRelease(appRef);
}