# Page Actions
## Contents
1. [Manifest](pageAction.html#manifest)
2. [UI的组成部分](pageAction.html#ui)
3. [提示](pageAction.html#tips)
4. [示例](pageAction.html#examples)
5. [API reference: chrome.pageAction](pageAction.html#apiReference)
1. [Methods](pageAction.html#global-methods)
1. [hide](pageAction.html#method-hide)
2. [setIcon](pageAction.html#method-setIcon)
3. [setPopup](pageAction.html#method-setPopup)
4. [setTitle](pageAction.html#method-setTitle)
5. [show](pageAction.html#method-show)
2. [Events](pageAction.html#global-events)
1. [onClicked](pageAction.html#event-onClicked)
使用page actions把图标放置到地址栏里。page actions定义需要处理的页面的事件，但是它们不是适用于所有页面的。下面是一些page actions的示例：
* 订阅该页面的RSS feed
* 为页面的图片做一个幻灯片
在下面的屏幕截图中的RSS图标，提供了一个可以让用户订阅当前页面RSS Feed的page action。
想让扩展图标总是可见，则使用[browser action](browserAction.html)。
**注意：** 打包的应用程序不能使用page actions。
## Manifest
在 [extension manifest](manifest.html) 中用下面的方式注册你的page action：
```
{
"name": "My extension",
...
**"page_action": {
"default_icon": "icons/foo.png", _// optional_
"default_title": "Do action", _// optional; shown in tooltip_
"default_popup": "popup.html" _// optional_
}**,
...
}
```
## UI的组成部分
同browser actions一样，page actions 可以有图标、提示信息、 弹出窗口。但没有badge，也因此，作为辅助，page actions可以有显示和消失两种状态。阅读[browser action UI](browserAction.html#ui). 可以找到图标、提示信息、 弹出窗口相关信息。
使用方法 [show()](#method-show) 和 [hide()](#method-hide) 可以显示和隐藏page action。缺省情况下page action是隐藏的。当要显示时，需要指定图标所在的标签页，图标显示后会一直可见，直到该标签页关闭或开始显示不同的URL （如：用户点击了一个连接）
## 提示
为了获得最佳的视觉效果，请遵循下列指导方针：
* **要**只对少数页面使用page action；
* **不要**对大多数页面使用它，如果功能需要，使用 [browser actions](browserAction.html)代替。
* **没事别总让图标出现动画，那会让人很烦。**
## 示例
你可以在[examples/api/pageAction](http://src.chromium.org/viewvc/chrome/trunk/src/chrome/common/extensions/docs/examples/api/pageAction/) 找到使用page action的简单示例，其它例子和源代码帮助查看[Samples](sample.html)。
## API reference: chrome.pageAction
### Properties
<a></a>
#### getLastError
chrome.extensionlastError
### Methods
#### hide
void chrome.pageAction.hide(, integer `tabId`)
Undocumented.
隐藏page action.
#### Parameters
`tabId`_( optional enumerated Type array of integer )_
Undocumented.
要执行这个动作的标签ID。
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key [minimum_chrome_version](manifest.html#minimum_chrome_version) can ensure that your extension won't be run in an earlier browser version.
#### Returns
#### Callback function
The callback _parameter_ should specify a function that looks like this:
If you specify the _callback_ parameter, it should specify a function that looks like this:
```
function(Type param1, Type param2) {...};
```
This function was added in version . If you require this function, the manifest key [minimum_chrome_version](manifest.html#minimum_chrome_version) can ensure that your extension won't be run in an earlier browser version.
#### setIcon
void chrome.pageAction.setIcon(, object `details`)
Undocumented.
为page aciton设置图标。图标可以是一个图片的路径或者是从一个canvas元素提取的像素信息.。无论是**图标路径**还是canvas的 **imageData**，这个属性必须被指定。
#### Parameters
`details`_( optional enumerated Type array of object )_
Undocumented.
Description of this parameter from the json schema.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key [minimum_chrome_version](manifest.html#minimum_chrome_version) can ensure that your extension won't be run in an earlier browser version.
`tabId`_( optional enumerated Type array of integer )_
Undocumented.
要执行这个动作的标签ID。
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key [minimum_chrome_version](manifest.html#minimum_chrome_version) can ensure that your extension won't be run in an earlier browser version.
`imageData`_( optional enumerated Type array of ImageData )_
Undocumented.
图片的像素信息。必须是一个ImageData 对象(例如：一个canvas元素)。
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key [minimum_chrome_version](manifest.html#minimum_chrome_version) can ensure that your extension won't be run in an earlier browser version.
`path`_( optional enumerated Type array of string )_
Undocumented.
图片在扩展中的的相对路径。
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key [minimum_chrome_version](manifest.html#minimum_chrome_version) can ensure that your extension won't be run in an earlier browser version.
`iconIndex`_( optional enumerated Type array of integer )_
Undocumented.
**不建议。**manifest中定义的，0开始的图标数组下标。
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key [minimum_chrome_version](manifest.html#minimum_chrome_version) can ensure that your extension won't be run in an earlier browser version.
#### Returns
#### Callback function
The callback _parameter_ should specify a function that looks like this:
If you specify the _callback_ parameter, it should specify a function that looks like this:
```
function(Type param1, Type param2) {...};
```
This function was added in version . If you require this function, the manifest key [minimum_chrome_version](manifest.html#minimum_chrome_version) can ensure that your extension won't be run in an earlier browser version.
#### setPopup
void chrome.pageAction.setPopup(, object `details`)
Undocumented.
设置一个点击page actions时显示在popup中的HTML。
#### Parameters
`details`_( optional enumerated Type array of object )_
Undocumented.
Description of this parameter from the json schema.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key [minimum_chrome_version](manifest.html#minimum_chrome_version) can ensure that your extension won't be run in an earlier browser version.
`tabId`_( optional enumerated Type array of integer )_
Undocumented.
要设置popup的标签ID。
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key [minimum_chrome_version](manifest.html#minimum_chrome_version) can ensure that your extension won't be run in an earlier browser version.
`popup`_( optional enumerated Type array of string )_
Undocumented.
popup中显示的html文件。如果设置为空字符('')，将不显示popup。
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key [minimum_chrome_version](manifest.html#minimum_chrome_version) can ensure that your extension won't be run in an earlier browser version.
#### Returns
#### Callback function
The callback _parameter_ should specify a function that looks like this:
If you specify the _callback_ parameter, it should specify a function that looks like this:
```
function(Type param1, Type param2) {...};
```
这个功能已经在**chromium 5.0.316.0版本**添加。如果你需要这个功能，可以通过manifest的[minimum_chrome_version](manifest.html#minimum_chrome_version)键值来确认你的扩展不会运行在早期的浏览器版本。
#### setTitle
void chrome.pageAction.setTitle(, object `details`)
Undocumented.
设置page action的标题，这将显示在tooltip中。
#### Parameters
`details`_( optional enumerated Type array of object )_
Undocumented.
Description of this parameter from the json schema.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key [minimum_chrome_version](manifest.html#minimum_chrome_version) can ensure that your extension won't be run in an earlier browser version.
`tabId`_( optional enumerated Type array of integer )_
Undocumented.
要设置标题的标签ID。
`title`_( optional enumerated Type array of string )_
Undocumented.
提示信息字符串。
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key [minimum_chrome_version](manifest.html#minimum_chrome_version) can ensure that your extension won't be run in an earlier browser version.
#### Returns
#### Callback function
The callback _parameter_ should specify a function that looks like this:
If you specify the _callback_ parameter, it should specify a function that looks like this:
```
function(Type param1, Type param2) {...};
```
This function was added in version . If you require this function, the manifest key [minimum_chrome_version](manifest.html#minimum_chrome_version) can ensure that your extension won't be run in an earlier browser version.
#### show
void chrome.pageAction.show(, integer `tabId`)
Undocumented.
显示page action，无论标签是否被选中。
#### Parameters
`tabId`_( optional enumerated Type array of integer )_
Undocumented.
要执行这个动作的标签ID。
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key [minimum_chrome_version](manifest.html#minimum_chrome_version) can ensure that your extension won't be run in an earlier browser version.
#### Returns
#### Callback function
The callback _parameter_ should specify a function that looks like this:
If you specify the _callback_ parameter, it should specify a function that looks like this:
```
function(Type param1, Type param2) {...};
```
This function was added in version . If you require this function, the manifest key [minimum_chrome_version](manifest.html#minimum_chrome_version) can ensure that your extension won't be run in an earlier browser version.
### Events
#### onClicked
chrome.pageAction.onClicked.addListener(function(Tab tab) {...});
Undocumented.
当page action图标被点击的时候调用，如果page action是一个popup，这个事件将不会触发。Fi
#### Parameters
`tab`_( optional enumerated [Tab](tabs.html#type-Tab) array of paramType )_
Undocumented.
Description of this parameter from the json schema.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key [minimum_chrome_version](manifest.html#minimum_chrome_version) can ensure that your extension won't be run in an earlier browser version.
### Types
<a></a>
#### type name
- 基础文档
- 综述
- 调试
- 格式：Manifest文件
- 模式匹配
- 改变浏览器外观
- Browser Actions
- Context Menus
- 桌面通知
- Omnibox
- Override替代页
- Page Actions
- 主题
- 与浏览器交互
- 书签
- Cookies
- chrome.devtools.* APIs
- Events
- chrome.history
- Management
- 标签
- 视窗
- 实现扩展
- 无障碍性(a11y)
- 背景页
- Content Scripts
- 跨域 XMLHttpRequest 请求
- 国际化 (i18n)
- 消息传递
- Optional Permissions
- NPAPI 插件
- 完成并发布应用
- 自动升级
- 托管
- 打包
- 规范和协议
- 应用设计规范
- 开发人员协议
- 免责声明