# app
> 控制应用的生命周期。
下面的示例展示在最后的窗口被关闭时如何退出应用：
```javascript
const {app} = require('electron')
app.on('window-all-closed', () => {
app.quit()
})
```
## 事件
`app` 对象发出以下事件：
### Event: 'will-finish-launching'
当应用完成基本的启动时被发送。在 Windows 和 Linux 上， `will-finish-launching` 事件和 `ready` 事件是相同的；在 macOS 上，这个事件代表 `NSApplication` 的 `applicationWillFinishLaunching` 通知。这里一般可以为 `open-file` 和 `open-url` 事件装配监听器、开始崩溃报告和自动更新。
大多数情况，应该在 `ready` 事件处理程序中做所有事情。
### Event: 'ready'
返回：
* `launchInfo` Object _macOS_
当 Electron 完成初始化后被发送。在 macOS 上，如果它从通知中心被运行， `launchInfo` 保存了 `NSUserNotification` 的 `userInfo` ，用于打开应用。你可以调用 `app.isReady()` 来检查这个事件是否被触发了。
### Event: 'window-all-closed'
当所有窗口被关闭后发送。
如果你没有订阅这个事件并且所有窗口被关闭，默认的行为是退出应用；然而，如果你订阅了，可以控制应用是否退出。如果用户按下 `Cmd + Q`，或者开发者调用了 `app.quit()`， Electron 会首先尝试关闭所有的窗口，然后发送 `will-quit` 事件，这种情况下，`window-all-closed` 事件不会被发送。
### Event: 'before-quit'
返回：
* `event` Event
在应用开始关闭它的窗口之前发送。调用 `event.preventDefault()` 将会阻止默认的行为，即终止应用。
### Event: 'will-quit'
返回：
* `event` Event
当所有窗口被关闭了，而且应用即将退出时发送。
调用 `event.preventDefault()` 将阻止默认行为，即终止应用。
查看 `window-all-closed` 事件的描述，了解 `will-quit` 事件和 `window-all-closed` 事件的区别。
### Event: 'quit'
返回：
* `event` Event
* `exitCode` Integer
当应用退出时发送。
### Event: 'open-file' _macOS_
返回：
* `event` Event
* `path` String
当用户想要使用应用打开一个文件时发送。 `open-file` 事件通常在应用已经打开，操作系统想要恢复应用来打开文件时发送。 `open-file` 在一个文件被丢到 dock 并且应用还未运行时发送。确保在你的应用启动的早起监听 `open-file` 事件以处理这个情况（甚至在 `ready` 事件发送之前）。
如果想要处理这个事件，你可以调用 `event.preventDefault()` 。
在 Windows 上，必须解析 `process.argv` （在主进程中） 来获得文件路径。
### Event: 'open-url' _macOS_
返回：
* `event` Event
* `url` String
当用户想要使用应用打开一个 URL 时发送。URL 结构必须注册为被你的应用打开。
如果你想处理这个事件，可以调用 `event.preventDefault()`。
### Event: 'activate' _macOS_
返回：
* `event` Event
* `hasVisibleWindows` Boolean
当应用被激活时发送，通常在用户点击了应用的 dock 图标时发生。
### Event: 'continue-activity' _macOS_
返回：
* `event` Event
* `type` String —— 一个字符串标识活动。映射到 [`NSUserActivity.activityType`][activity-type]。
* `userInfo` Object —— 包括其它设备上的 activity 保存的 app 特定的状态。
当一个从其它不同设备的 activity 想要被恢复，[Handoff][handoff] 期间发送。如果你要处理这个事件，可以调用 `event.preventDefault()`。
用户的一个 activity 只有在一个有同样开发者团队 ID 作为 activity 的源 app 和 支持 activity 的类型的应用中 可以被继续。
支持的 activity 类型在应用的 `Info.plist` 中 `NSUserActivityTypes` key 上指定。
### Event: 'browser-window-blur'
返回：
* `event` Event
* `window` BrowserWindow
当一个 [browserWindow](browser-window.md) 失去焦点时发送。
### Event: 'browser-window-focus'
返回：
* `event` Event
* `window` BrowserWindow
当一个 [browserWindow](browser-window.md) 获得焦点时发送。
### Event: 'browser-window-created'
返回：
* `event` Event
* `window` BrowserWindow
当一个新的 [browserWindow](browser-window.md) 被创建时发送。
### Event: 'web-contents-created'
返回：
* `event` Event
* `webContents` WebContents
当一个新的 [webContents](web-contents.md) 被创建时发送。
### Event: 'certificate-error'
返回：
* `event` Event
* `webContents` [WebContents](web-contents.md)
* `url` URL
* `error` String —— 错误码
* `certificate` [Certificate](structures/certificate.md)
* `callback` Function
* `isTrusted` Boolean —— 是否认为证书是可信的。
当验证 `url` 的 `certificate` 失败的时候发送，要信任证书，你可以阻止默认的行为，通过调用 `event.preventDefault()` ，并调用 `callback(true)`。
```javascript
const {app} = require('electron')
app.on('certificate-error', (event, webContents, url, error, certificate, callback) => {
if (url === 'https://github.com') {
// Verification logic.
event.preventDefault()
callback(true)
} else {
callback(false)
}
})
```
### Event: 'select-client-certificate'
返回：
* `event` Event
* `webContents` [WebContents](web-contents.md)
* `url` URL
* `certificateList` [Certificate[]](structures/certificate.md)
* `callback` Function
* `certificate` [Certificate](structures/certificate.md)
当一个客户端证书被请求时发送。
The `url` corresponds to the navigation entry requesting the client certificate
and `callback` needs to be called with an entry filtered from the list. Using
`event.preventDefault()` prevents the application from using the first
certificate from the store.
```javascript
const {app} = require('electron')
app.on('select-client-certificate', (event, webContents, url, list, callback) => {
event.preventDefault()
callback(list[0])
})
```
### Event: 'login'
Returns:
* `event` Event
* `webContents` [WebContents](web-contents.md)
* `request` Object
* `method` String
* `url` URL
* `referrer` URL
* `authInfo` Object
* `isProxy` Boolean
* `scheme` String
* `host` String
* `port` Integer
* `realm` String
* `callback` Function
* `username` String
* `password` String
Emitted when `webContents` wants to do basic auth.
The default behavior is to cancel all authentications, to override this you
should prevent the default behavior with `event.preventDefault()` and call
`callback(username, password)` with the credentials.
```javascript
const {app} = require('electron')
app.on('login', (event, webContents, request, authInfo, callback) => {
event.preventDefault()
callback('username', 'secret')
})
```
### Event: 'gpu-process-crashed'
返回：
* `event` Event
* `killed` Boolean
当 gpu 进程崩溃或者被杀死时发送。
### Event: 'accessibility-support-changed' _macOS_ _Windows_
Returns:
* `event` Event
* `accessibilitySupportEnabled` Boolean - `true` when Chrome's accessibility
support is enabled, `false` otherwise.
Emitted when Chrome's accessibility support changes. This event fires when
assistive technologies, such as screen readers, are enabled or disabled.
See https://www.chromium.org/developers/design-documents/accessibility for more
details.
## 方法
`app` 对象有以下方法：
**注意：** 一些方法只能在特定操作系统使用，文档中进行标记。
### `app.quit()`
Try to close all windows. The `before-quit` event will be emitted first. If all
windows are successfully closed, the `will-quit` event will be emitted and by
default the application will terminate.
This method guarantees that all `beforeunload` and `unload` event handlers are
correctly executed. It is possible that a window cancels the quitting by
returning `false` in the `beforeunload` event handler.
### `app.exit([exitCode])`
* `exitCode` Integer (optional)
Exits immediately with `exitCode`. `exitCode` defaults to 0.
All windows will be closed immediately without asking user and the `before-quit`
and `will-quit` events will not be emitted.
### `app.relaunch([options])`
* `options` Object (optional)
* `args` String[] (optional)
* `execPath` String (optional)
Relaunches the app when current instance exits.
By default the new instance will use the same working directory and command line
arguments with current instance. When `args` is specified, the `args` will be
passed as command line arguments instead. When `execPath` is specified, the
`execPath` will be executed for relaunch instead of current app.
Note that this method does not quit the app when executed, you have to call
`app.quit` or `app.exit` after calling `app.relaunch` to make the app restart.
When `app.relaunch` is called for multiple times, multiple instances will be
started after current instance exited.
An example of restarting current instance immediately and adding a new command
line argument to the new instance:
```javascript
const {app} = require('electron')
app.relaunch({args: process.argv.slice(1).concat(['--relaunch'])})
app.exit(0)
```
### `app.isReady()`
Returns `Boolean` - `true` if Electron has finished initializing, `false` otherwise.
### `app.focus()`
On Linux, focuses on the first visible window. On macOS, makes the application
the active app. On Windows, focuses on the application's first window.
### `app.hide()` _macOS_
Hides all application windows without minimizing them.
### `app.show()` _macOS_
Shows application windows after they were hidden. Does not automatically focus
them.
### `app.getAppPath()`
Returns `String` - The current application directory.
### `app.getPath(name)`
* `name` String
Returns `String` - A path to a special directory or file associated with `name`. On
failure an `Error` is thrown.
You can request the following paths by the name:
* `home` User's home directory.
* `appData` Per-user application data directory, which by default points to:
* `%APPDATA%` on Windows
* `$XDG_CONFIG_HOME` or `~/.config` on Linux
* `~/Library/Application Support` on macOS
* `userData` The directory for storing your app's configuration files, which by
default it is the `appData` directory appended with your app's name.
* `temp` Temporary directory.
* `exe` The current executable file.
* `module` The `libchromiumcontent` library.
* `desktop` The current user's Desktop directory.
* `documents` Directory for a user's "My Documents".
* `downloads` Directory for a user's downloads.
* `music` Directory for a user's music.
* `pictures` Directory for a user's pictures.
* `videos` Directory for a user's videos.
* `pepperFlashSystemPlugin` Full path to the system version of the Pepper Flash plugin.
### `app.setPath(name, path)`
* `name` String
* `path` String
Overrides the `path` to a special directory or file associated with `name`. If
the path specifies a directory that does not exist, the directory will be
created by this method. On failure an `Error` is thrown.
You can only override paths of a `name` defined in `app.getPath`.
By default, web pages' cookies and caches will be stored under the `userData`
directory. If you want to change this location, you have to override the
`userData` path before the `ready` event of the `app` module is emitted.
### `app.getVersion()`
Returns `String` - The version of the loaded application. If no version is found in the
application's `package.json` file, the version of the current bundle or
executable is returned.
### `app.getName()`
Returns `String` - The current application's name, which is the name in the application's
`package.json` file.
Usually the `name` field of `package.json` is a short lowercased name, according
to the npm modules spec. You should usually also specify a `productName`
field, which is your application's full capitalized name, and which will be
preferred over `name` by Electron.
### `app.setName(name)`
* `name` String
Overrides the current application's name.
### `app.getLocale()`
Returns `String` - The current application locale. Possible return values are documented
[here](locales.md).
**Note:** When distributing your packaged app, you have to also ship the
`locales` folder.
**Note:** On Windows you have to call it after the `ready` events gets emitted.
### `app.addRecentDocument(path)` _macOS_ _Windows_
* `path` String
Adds `path` to the recent documents list.
This list is managed by the OS. On Windows you can visit the list from the task
bar, and on macOS you can visit it from dock menu.
### `app.clearRecentDocuments()` _macOS_ _Windows_
Clears the recent documents list.
### `app.setAsDefaultProtocolClient(protocol[, path, args])` _macOS_ _Windows_
* `protocol` String - The name of your protocol, without `://`. If you want your
app to handle `electron://` links, call this method with `electron` as the
parameter.
* `path` String (optional) _Windows_ - Defaults to `process.execPath`
* `args` String[] (optional) _Windows_ - Defaults to an empty array
Returns `Boolean` - Whether the call succeeded.
This method sets the current executable as the default handler for a protocol
(aka URI scheme). It allows you to integrate your app deeper into the operating
system. Once registered, all links with `your-protocol://` will be opened with
the current executable. The whole link, including protocol, will be passed to
your application as a parameter.
On Windows you can provide optional parameters path, the path to your executable,
and args, an array of arguments to be passed to your executable when it launches.
**Note:** On macOS, you can only register protocols that have been added to
your app's `info.plist`, which can not be modified at runtime. You can however
change the file with a simple text editor or script during build time.
Please refer to [Apple's documentation][CFBundleURLTypes] for details.
The API uses the Windows Registry and LSSetDefaultHandlerForURLScheme internally.
### `app.removeAsDefaultProtocolClient(protocol[, path, args])` _macOS_ _Windows_
* `protocol` String - The name of your protocol, without `://`.
* `path` String (optional) _Windows_ - Defaults to `process.execPath`
* `args` String[] (optional) _Windows_ - Defaults to an empty array
Returns `Boolean` - Whether the call succeeded.
This method checks if the current executable as the default handler for a
protocol (aka URI scheme). If so, it will remove the app as the default handler.
### `app.isDefaultProtocolClient(protocol[, path, args])` _macOS_ _Windows_
* `protocol` String - The name of your protocol, without `://`.
* `path` String (optional) _Windows_ - Defaults to `process.execPath`
* `args` String[] (optional) _Windows_ - Defaults to an empty array
Returns `Boolean`
This method checks if the current executable is the default handler for a protocol
(aka URI scheme). If so, it will return true. Otherwise, it will return false.
**Note:** On macOS, you can use this method to check if the app has been
registered as the default protocol handler for a protocol. You can also verify
this by checking `~/Library/Preferences/com.apple.LaunchServices.plist` on the
macOS machine. Please refer to
[Apple's documentation][LSCopyDefaultHandlerForURLScheme] for details.
The API uses the Windows Registry and LSCopyDefaultHandlerForURLScheme internally.
### `app.setUserTasks(tasks)` _Windows_
* `tasks` [Task[]](structures/task.md) - Array of `Task` objects
Adds `tasks` to the [Tasks][tasks] category of the JumpList on Windows.
`tasks` is an array of `Task` objects in the following format:
`Task` Object:
* `program` String - Path of the program to execute, usually you should
specify `process.execPath` which opens the current program.
* `arguments` String - The command line arguments when `program` is
executed.
* `title` String - The string to be displayed in a JumpList.
* `description` String - Description of this task.
* `iconPath` String - The absolute path to an icon to be displayed in a
JumpList, which can be an arbitrary resource file that contains an icon. You
can usually specify `process.execPath` to show the icon of the program.
* `iconIndex` Integer - The icon index in the icon file. If an icon file
consists of two or more icons, set this value to identify the icon. If an
icon file consists of one icon, this value is 0.
Returns `Boolean` - Whether the call succeeded.
**Note:** If you'd like to customize the Jump List even more use
`app.setJumpList(categories)` instead.
### `app.getJumpListSettings()` _Windows_
Returns `Object`:
* `minItems` Integer - The minimum number of items that will be shown in the
Jump List (for a more detailed description of this value see the
[MSDN docs][JumpListBeginListMSDN]).
* `removedItems` [JumpListItem[]](structures/jump-list-item.md) - Array of `JumpListItem` objects that correspond to
items that the user has explicitly removed from custom categories in the
Jump List. These items must not be re-added to the Jump List in the **next**
call to `app.setJumpList()`, Windows will not display any custom category
that contains any of the removed items.
### `app.setJumpList(categories)` _Windows_
* `categories` [JumpListCategory[]](structures/jump-list-category.md) or `null` - Array of `JumpListCategory` objects.
Sets or removes a custom Jump List for the application, and returns one of the
following strings:
* `ok` - Nothing went wrong.
* `error` - One or more errors occurred, enable runtime logging to figure out
the likely cause.
* `invalidSeparatorError` - An attempt was made to add a separator to a
custom category in the Jump List. Separators are only allowed in the
standard `Tasks` category.
* `fileTypeRegistrationError` - An attempt was made to add a file link to
the Jump List for a file type the app isn't registered to handle.
* `customCategoryAccessDeniedError` - Custom categories can't be added to the
Jump List due to user privacy or group policy settings.
If `categories` is `null` the previously set custom Jump List (if any) will be
replaced by the standard Jump List for the app (managed by Windows).
`JumpListCategory` objects should have the following properties:
* `type` String - One of the following:
* `tasks` - Items in this category will be placed into the standard `Tasks`
category. There can be only one such category, and it will always be
displayed at the bottom of the Jump List.
* `frequent` - Displays a list of files frequently opened by the app, the
name of the category and its items are set by Windows.
* `recent` - Displays a list of files recently opened by the app, the name
of the category and its items are set by Windows. Items may be added to
this category indirectly using `app.addRecentDocument(path)`.
* `custom` - Displays tasks or file links, `name` must be set by the app.
* `name` String - Must be set if `type` is `custom`, otherwise it should be
omitted.
* `items` Array - Array of `JumpListItem` objects if `type` is `tasks` or
`custom`, otherwise it should be omitted.
**Note:** If a `JumpListCategory` object has neither the `type` nor the `name`
property set then its `type` is assumed to be `tasks`. If the `name` property
is set but the `type` property is omitted then the `type` is assumed to be
`custom`.
**Note:** Users can remove items from custom categories, and Windows will not
allow a removed item to be added back into a custom category until **after**
the next successful call to `app.setJumpList(categories)`. Any attempt to
re-add a removed item to a custom category earlier than that will result in the
entire custom category being omitted from the Jump List. The list of removed
items can be obtained using `app.getJumpListSettings()`.
`JumpListItem` objects should have the following properties:
* `type` String - One of the following:
* `task` - A task will launch an app with specific arguments.
* `separator` - Can be used to separate items in the standard `Tasks`
category.
* `file` - A file link will open a file using the app that created the
Jump List, for this to work the app must be registered as a handler for
the file type (though it doesn't have to be the default handler).
* `path` String - Path of the file to open, should only be set if `type` is
`file`.
* `program` String - Path of the program to execute, usually you should
specify `process.execPath` which opens the current program. Should only be
set if `type` is `task`.
* `args` String - The command line arguments when `program` is executed. Should
only be set if `type` is `task`.
* `title` String - The text to be displayed for the item in the Jump List.
Should only be set if `type` is `task`.
* `description` String - Description of the task (displayed in a tooltip).
Should only be set if `type` is `task`.
* `iconPath` String - The absolute path to an icon to be displayed in a
Jump List, which can be an arbitrary resource file that contains an icon
(e.g. `.ico`, `.exe`, `.dll`). You can usually specify `process.execPath` to
show the program icon.
* `iconIndex` Integer - The index of the icon in the resource file. If a
resource file contains multiple icons this value can be used to specify the
zero-based index of the icon that should be displayed for this task. If a
resource file contains only one icon, this property should be set to zero.
Here's a very simple example of creating a custom Jump List:
```javascript
const {app} = require('electron')
app.setJumpList([
{
type: 'custom',
name: 'Recent Projects',
items: [
{ type: 'file', path: 'C:\\Projects\\project1.proj' },
{ type: 'file', path: 'C:\\Projects\\project2.proj' }
]
},
{ // has a name so `type` is assumed to be "custom"
name: 'Tools',
items: [
{
type: 'task',
title: 'Tool A',
program: process.execPath,
args: '--run-tool-a',
icon: process.execPath,
iconIndex: 0,
description: 'Runs Tool A'
},
{
type: 'task',
title: 'Tool B',
program: process.execPath,
args: '--run-tool-b',
icon: process.execPath,
iconIndex: 0,
description: 'Runs Tool B'
}
]
},
{ type: 'frequent' },
{ // has no name and no type so `type` is assumed to be "tasks"
items: [
{
type: 'task',
title: 'New Project',
program: process.execPath,
args: '--new-project',
description: 'Create a new project.'
},
{ type: 'separator' },
{
type: 'task',
title: 'Recover Project',
program: process.execPath,
args: '--recover-project',
description: 'Recover Project'
}
]
}
])
```
### `app.makeSingleInstance(callback)`
* `callback` Function
* `argv` String[] - An array of the second instance's command line arguments
* `workingDirectory` String - The second instance's working directory
This method makes your application a Single Instance Application - instead of
allowing multiple instances of your app to run, this will ensure that only a
single instance of your app is running, and other instances signal this
instance and exit.
`callback` will be called with `callback(argv, workingDirectory)` when a second
instance has been executed. `argv` is an Array of the second instance's command
line arguments, and `workingDirectory` is its current working directory. Usually
applications respond to this by making their primary window focused and
non-minimized.
The `callback` is guaranteed to be executed after the `ready` event of `app`
gets emitted.
This method returns `false` if your process is the primary instance of the
application and your app should continue loading. And returns `true` if your
process has sent its parameters to another instance, and you should immediately
quit.
On macOS the system enforces single instance automatically when users try to open
a second instance of your app in Finder, and the `open-file` and `open-url`
events will be emitted for that. However when users start your app in command
line the system's single instance mechanism will be bypassed and you have to
use this method to ensure single instance.
An example of activating the window of primary instance when a second instance
starts:
```javascript
const {app} = require('electron')
let myWindow = null
const shouldQuit = app.makeSingleInstance((commandLine, workingDirectory) => {
// Someone tried to run a second instance, we should focus our window.
if (myWindow) {
if (myWindow.isMinimized()) myWindow.restore()
myWindow.focus()
}
})
if (shouldQuit) {
app.quit()
}
// Create myWindow, load the rest of the app, etc...
app.on('ready', () => {
})
```
### `app.releaseSingleInstance()`
Releases all locks that were created by `makeSingleInstance`. This will allow
multiple instances of the application to once again run side by side.
### `app.setUserActivity(type, userInfo[, webpageURL])` _macOS_
* `type` String - Uniquely identifies the activity. Maps to
[`NSUserActivity.activityType`][activity-type].
* `userInfo` Object - App-specific state to store for use by another device.
* `webpageURL` String - The webpage to load in a browser if no suitable app is
installed on the resuming device. The scheme must be `http` or `https`.
Creates an `NSUserActivity` and sets it as the current activity. The activity
is eligible for [Handoff][handoff] to another device afterward.
### `app.getCurrentActivityType()` _macOS_
Returns `String` - The type of the currently running activity.
### `app.setAppUserModelId(id)` _Windows_
* `id` String
Changes the [Application User Model ID][app-user-model-id] to `id`.
### `app.importCertificate(options, callback)` _LINUX_
* `options` Object
* `certificate` String - Path for the pkcs12 file.
* `password` String - Passphrase for the certificate.
* `callback` Function
* `result` Integer - Result of import.
Imports the certificate in pkcs12 format into the platform certificate store.
`callback` is called with the `result` of import operation, a value of `0`
indicates success while any other value indicates failure according to chromium [net_error_list](https://code.google.com/p/chromium/codesearch#chromium/src/net/base/net_error_list.h).
### `app.disableHardwareAcceleration()`
Disables hardware acceleration for current app.
This method can only be called before app is ready.
### `app.setBadgeCount(count)` _Linux_ _macOS_
* `count` Integer
Returns `Boolean` - Whether the call succeeded.
Sets the counter badge for current app. Setting the count to `0` will hide the
badge.
On macOS it shows on the dock icon. On Linux it only works for Unity launcher,
**Note:** Unity launcher requires the exsistence of a `.desktop` file to work,
for more information please read [Desktop Environment Integration][unity-requiremnt].
### `app.getBadgeCount()` _Linux_ _macOS_
Returns `Integer` - The current value displayed in the counter badge.
### `app.isUnityRunning()` _Linux_
Returns `Boolean` - Whether the current desktop environment is Unity launcher.
### `app.getLoginItemSettings()` _macOS_ _Windows_
Returns `Object`:
* `openAtLogin` Boolean - `true` if the app is set to open at login.
* `openAsHidden` Boolean - `true` if the app is set to open as hidden at login.
This setting is only supported on macOS.
* `wasOpenedAtLogin` Boolean - `true` if the app was opened at login
automatically. This setting is only supported on macOS.
* `wasOpenedAsHidden` Boolean - `true` if the app was opened as a hidden login
item. This indicates that the app should not open any windows at startup.
This setting is only supported on macOS.
* `restoreState` Boolean - `true` if the app was opened as a login item that
should restore the state from the previous session. This indicates that the
app should restore the windows that were open the last time the app was
closed. This setting is only supported on macOS.
**Note:** This API has no effect on
[MAS builds][mas-builds].
### `app.setLoginItemSettings(settings)` _macOS_ _Windows_
* `settings` Object
* `openAtLogin` Boolean - `true` to open the app at login, `false` to remove
the app as a login item. Defaults to `false`.
* `openAsHidden` Boolean - `true` to open the app as hidden. Defaults to
`false`. The user can edit this setting from the System Preferences so
`app.getLoginItemStatus().wasOpenedAsHidden` should be checked when the app
is opened to know the current value. This setting is only supported on
macOS.
Set the app's login item settings.
**Note:** This API has no effect on
[MAS builds][mas-builds].
### `app.isAccessibilitySupportEnabled()` _macOS_ _Windows_
Returns `Boolean` - `true` if Chrome's accessibility support is enabled,
`false` otherwise. This API will return `true` if the use of assistive
technologies, such as screen readers, has been detected. See
https://www.chromium.org/developers/design-documents/accessibility for more
details.
### `app.setAboutPanelOptions(options)` _macOS_
* `options` Object
* `applicationName` String (optional) - The app's name.
* `applicationVersion` String (optional) - The app's version.
* `copyright` String (optional) - Copyright information.
* `credits` String (optional) - Credit information.
* `version` String (optional) - The app's build version number.
Set the about panel options. This will override the values defined in the app's
`.plist` file. See the [Apple docs][about-panel-options] for more details.
### `app.commandLine.appendSwitch(switch[, value])`
* `switch` String - A command-line switch
* `value` String (optional) - A value for the given switch
Append a switch (with optional `value`) to Chromium's command line.
**Note:** This will not affect `process.argv`, and is mainly used by developers
to control some low-level Chromium behaviors.
### `app.commandLine.appendArgument(value)`
* `value` String - The argument to append to the command line
Append an argument to Chromium's command line. The argument will be quoted
correctly.
**Note:** This will not affect `process.argv`.
### `app.dock.bounce([type])` _macOS_
* `type` String (optional) - Can be `critical` or `informational`. The default is
`informational`
When `critical` is passed, the dock icon will bounce until either the
application becomes active or the request is canceled.
When `informational` is passed, the dock icon will bounce for one second.
However, the request remains active until either the application becomes active
or the request is canceled.
Returns an ID representing the request.
### `app.dock.cancelBounce(id)` _macOS_
* `id` Integer
Cancel the bounce of `id`.
### `app.dock.downloadFinished(filePath)` _macOS_
* `filePath` String
Bounces the Downloads stack if the filePath is inside the Downloads folder.
### `app.dock.setBadge(text)` _macOS_
* `text` String
Sets the string to be displayed in the dock’s badging area.
### `app.dock.getBadge()` _macOS_
Returns `String` - The badge string of the dock.
### `app.dock.hide()` _macOS_
Hides the dock icon.
### `app.dock.show()` _macOS_
Shows the dock icon.
### `app.dock.isVisible()` _macOS_
Returns `Boolean` - Whether the dock icon is visible.
The `app.dock.show()` call is asynchronous so this method might not
return true immediately after that call.
### `app.dock.setMenu(menu)` _macOS_
* `menu` [Menu](menu.md)
Sets the application's [dock menu][dock-menu].
### `app.dock.setIcon(image)` _macOS_
* `image` [NativeImage](native-image.md)
Sets the `image` associated with this dock icon.
[dock-menu]:https://developer.apple.com/library/mac/documentation/Carbon/Conceptual/customizing_docktile/concepts/dockconcepts.html#//apple_ref/doc/uid/TP30000986-CH2-TPXREF103
[tasks]:http://msdn.microsoft.com/en-us/library/windows/desktop/dd378460(v=vs.85).aspx#tasks
[app-user-model-id]: https://msdn.microsoft.com/en-us/library/windows/desktop/dd378459(v=vs.85).aspx
[CFBundleURLTypes]: https://developer.apple.com/library/ios/documentation/General/Reference/InfoPlistKeyReference/Articles/CoreFoundationKeys.html#//apple_ref/doc/uid/TP40009249-102207-TPXREF115
[LSCopyDefaultHandlerForURLScheme]: https://developer.apple.com/library/mac/documentation/Carbon/Reference/LaunchServicesReference/#//apple_ref/c/func/LSCopyDefaultHandlerForURLScheme
[handoff]: https://developer.apple.com/library/ios/documentation/UserExperience/Conceptual/Handoff/HandoffFundamentals/HandoffFundamentals.html
[activity-type]: https://developer.apple.com/library/ios/documentation/Foundation/Reference/NSUserActivity_Class/index.html#//apple_ref/occ/instp/NSUserActivity/activityType
[unity-requiremnt]: ../tutorial/desktop-environment-integration.md#unity-launcher-shortcuts-linux
[mas-builds]: ../tutorial/mac-app-store-submission-guide.md
[JumpListBeginListMSDN]: https://msdn.microsoft.com/en-us/library/windows/desktop/dd378398(v=vs.85).aspx
[about-panel-options]: https://developer.apple.com/reference/appkit/nsapplication/1428479-orderfrontstandardaboutpanelwith?language=objc
- 索引
- 前言.关于Electron
- 第一部分 开发指南
- 第1章.平台支持
- 第2章.安全、原生功能和你的责任
- 第3章.版本说明
- 第4章.发行应用
- 第5章.Mac App商店提交指南
- 第6章.Windows商店指南
- 第7章.应用打包
- 第8章.使用Node原生模块
- 第9章.调试主进程
- 9.1.在VSCode中调试
- 9.2.在node-inspector中调试
- 第10章.使用Selenium和WebDriver
- 第11章.DevTools扩展
- 第12章.使用Pepper Flash插件
- 第13章.使用Widevine CDM插件
- 第14章.通过自动化持续集成系统进行测试
- 第15章.离屏渲染
- 第二部分 使用教程
- 第16章.快速入门
- 第17章.桌面环境集成
- 第18章.在线/离线事件探测
- 第19章.应答式编译器（REPL）
- 第三部分 API参考
- 第20章.API简介
- 第21章.进程对象
- 第22章.Chrome的命令行开关
- 第23章.环境变量
- 第24章.定制的DOM元素
- 24.1.File 对象
- 24.2.webview 标签
- 第25章.主进程模块
- 25.1.app
- 25.2.BrowserWindow
- 25.3.无框架窗口
- 第26章.渲染进程模块
- 第27章.两种进程可用的模块
- 第四部分 高级主题
- 附 FAQ
- 附 文档规范
- 附 示例用例
- 1.无边框窗口