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paramName
( optional enumerated Type 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 can ensure that your extension won't be run in an earlier browser version.
Parameters

Google Chrome Extensions (Labs)

chrome.experimental.extension

For information on how to use experimental APIs, see the chrome.experimental.* APIs page.

API reference: chrome.experimental.extension

Types

Preference

paramName
( Type array of object )
An object which allows access to a preference.
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 can ensure that your extension won't be run in an earlier browser version.

Methods of Preference

clear

void preference.clear(, object details, function callback)

Clears the setting in the user preferences. This way default settings can become effective again.

Parameters

details
( Type array of object )
What setting to clear.
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 can ensure that your extension won't be run in an earlier browser version.
incognito
( optional Type array of boolean )
Whether to clear the setting for the incognito session only (default false).
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 can ensure that your extension won't be run in an earlier browser version.
callback
( optional Type array of function )
Called after the preference has been cleared.
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 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() {...};

This function was added in version . If you require this function, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

get

void preference.get(, object details, function callback)

Get the setting from the user preferences.

Parameters

details
( Type array of object )
What setting to return.
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 can ensure that your extension won't be run in an earlier browser version.
incognito
( optional Type array of boolean )
Whether to return the setting that applies to the incognito session (default false).
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 can ensure that your extension won't be run in an earlier browser version.
callback
( Type array of function )
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 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(object details) {...};
details
( Type array of object )
Details of the currently effective preference value.
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 can ensure that your extension won't be run in an earlier browser version.
value
( Type array of any )
The value of the preference.
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 can ensure that your extension won't be run in an earlier browser version.
levelOfControl
( enumerated Type array of string ["NotControllable", "ControlledByOtherExtensions", "ControllableByThisExtension", "ControlledByThisExtension"] )
One of
NotControllable: cannot be controlled by any extension
ControlledByOtherExtensions: controlled by extensions with higher precedence
ControllableByThisExtension: can be controlled by this extension
ControlledByThisExtension: controlled by this extension
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 can ensure that your extension won't be run in an earlier browser version.
incognitoSpecific
( optional Type array of boolean )
Whether the effective value is specific to the incognito session.
This property will only be present if the incognito property in the details parameter of get() was true.
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 can ensure that your extension won't be run in an earlier browser version.

This function was added in version . If you require this function, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

set

void preference.set(, object details, function callback)

Set the setting in the user preferences

Parameters

details
( Type array of object )
What setting to change.
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 can ensure that your extension won't be run in an earlier browser version.
value
( Type array of any )
The value of the preference.
Note that every preference has a specific value type, which is described together with the preference. An extension should not set a preference value of a different type.
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 can ensure that your extension won't be run in an earlier browser version.
incognito
( optional Type array of boolean )
Whether to modify the setting for the incognito session only (default false).
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 can ensure that your extension won't be run in an earlier browser version.
callback
( optional Type array of function )
Called after the preference has been set.
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 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() {...};

This function was added in version . If you require this function, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

Events of Preference

onChange

preference.onChange.addListener(function(object details) {...});

Fired when the value of the preference changes.

Parameters

details
( 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 can ensure that your extension won't be run in an earlier browser version.
value
( Type array of any )
The value of the preference.
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 can ensure that your extension won't be run in an earlier browser version.
levelOfControl
( enumerated Type array of string ["NotControllable", "ControlledByOtherExtensions", "ControllableByThisExtension", "ControlledByThisExtension"] )
One of
NotControllable: cannot be controlled by any extension
ControlledByOtherExtensions: controlled by extensions with higher precedence
ControllableByThisExtension: can be controlled by this extension
ControlledByThisExtension: controlled by this extension
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 can ensure that your extension won't be run in an earlier browser version.
incognitoSpecific
( optional Type array of boolean )
Whether the value that has changed is specific to the incognito session.
This property will only be present if the user has enabled the extension in incognito mode.
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 can ensure that your extension won't be run in an earlier browser version.