chrome.input.ime

Description: Use the chrome.input.ime API to implement a custom IME for Chrome OS. This allows your extension to handle keystrokes, set the composition, and manage the candidate window.
Availability: Since Chrome 21.
Permissions: "input"

Manifest

You must declare the "input" permission in the extension manifest to use the input.ime API. For example:

      {
        "name": "My extension",
        ...
        "permissions": [
          "input"
        ],
        ...
      }

Examples

The following code creates an IME that converts typed letters to upper case.

      var context_id = -1;
      
      chrome.input.ime.onFocus.addListener(function(context) {
        context_id = context.contextID;
      });
      
      chrome.input.ime.onKeyEvent.addListener(
        function(engineID, keyData) {
          if (keyData.type == "keydown" && keyData.key.match(/^[a-z]$/)) {
            chrome.input.ime.commitText({"contextID": context_id,
                                         "text": keyData.key.toUpperCase()});
            return true;
          } else {
            return false;
          }
        });
      

For an example of using this API, see the basic input.ime sample. For other examples and for help in viewing the source code, see Samples.

Summary

Types
KeyboardEventType
KeyboardEvent
InputContextType
InputContext
MenuItemStyle
MenuItem
UnderlineStyle
WindowPosition
ScreenType
CallbackStyle
MouseButton
Methods
setComposition chrome.input.ime.setComposition(object parameters, function callback)
clearComposition chrome.input.ime.clearComposition(object parameters, function callback)
commitText chrome.input.ime.commitText(object parameters, function callback)
sendKeyEvents chrome.input.ime.sendKeyEvents(object parameters, function callback)
hideInputView chrome.input.ime.hideInputView()
setCandidateWindowProperties chrome.input.ime.setCandidateWindowProperties(object parameters, function callback)
setCandidates chrome.input.ime.setCandidates(object parameters, function callback)
setCursorPosition chrome.input.ime.setCursorPosition(object parameters, function callback)
setMenuItems chrome.input.ime.setMenuItems(object parameters, function callback)
updateMenuItems chrome.input.ime.updateMenuItems(object parameters, function callback)
deleteSurroundingText chrome.input.ime.deleteSurroundingText(object parameters, function callback)
keyEventHandled chrome.input.ime.keyEventHandled(string requestId, boolean response)
Events
onActivate
onDeactivated
onFocus
onBlur
onInputContextUpdate
onKeyEvent
onCandidateClicked
onMenuItemActivated
onSurroundingTextChanged
onReset

Types

KeyboardEventType

Enum
"keyup", or "keydown"

KeyboardEvent

See http://www.w3.org/TR/DOM-Level-3-Events/#events-KeyboardEvent
properties
KeyboardEventType type

One of keyup or keydown.

string requestId

The ID of the request.

string (optional) extensionId

Since Chrome 34.

The extension ID of the sender of this keyevent.

string key

Value of the key being pressed

string code

Since Chrome 26.

Value of the physical key being pressed. The value is not affected by current keyboard layout or modifier state.

integer (optional) keyCode

Since Chrome 37.

The deprecated HTML keyCode, which is system- and implementation-dependent numerical code signifying the unmodified identifier associated with the key pressed.

boolean (optional) altKey

Whether or not the ALT key is pressed.

boolean (optional) ctrlKey

Whether or not the CTRL key is pressed.

boolean (optional) shiftKey

Whether or not the SHIFT key is pressed.

boolean (optional) capsLock

Since Chrome 29.

Whether or not the CAPS_LOCK is enabled.

InputContextType

Type of value this text field edits, (Text, Number, URL, etc)
Enum
"text", "search", "tel", "url", "email", "number", or "password"

InputContext

Describes an input Context
properties
integer contextID

This is used to specify targets of text field operations. This ID becomes invalid as soon as onBlur is called.

InputContextType type

Type of value this text field edits, (Text, Number, URL, etc)

boolean autoCorrect

Since Chrome 40.

Whether the text field wants auto-correct.

boolean autoComplete

Since Chrome 40.

Whether the text field wants auto-complete.

boolean spellCheck

Since Chrome 40.

Whether the text field wants spell-check.

MenuItemStyle

The type of menu item. Radio buttons between separators are considered grouped.
Enum
"check", "radio", or "separator"

MenuItem

Since Chrome 30.

A menu item used by an input method to interact with the user from the language menu.
properties
string id

String that will be passed to callbacks referencing this MenuItem.

string (optional) label

Text displayed in the menu for this item.

MenuItemStyle (optional) style

The type of menu item.

boolean (optional) visible

Indicates this item is visible.

boolean (optional) checked

Indicates this item should be drawn with a check.

boolean (optional) enabled

Indicates this item is enabled.

UnderlineStyle

The type of the underline to modify this segment.
Enum
"underline", "doubleUnderline", or "noUnderline"

WindowPosition

Where to display the candidate window. If set to 'cursor', the window follows the cursor. If set to 'composition', the window is locked to the beginning of the composition.
Enum
"cursor", or "composition"

ScreenType

The screen type under which the IME is activated.
Enum
"normal", "login", "lock", or "secondary-login"

CallbackStyle

Enum
or "async"

MouseButton

Which mouse buttons was clicked.
Enum
"left", "middle", or "right"

Methods

setComposition

chrome.input.ime.setComposition(object parameters, function callback)

Set the current composition. If this extension does not own the active IME, this fails.

Parameters
object parameters
integer contextID

ID of the context where the composition text will be set

string text

Text to set

integer (optional) selectionStart

Position in the text that the selection starts at.

integer (optional) selectionEnd

Position in the text that the selection ends at.

integer cursor

Position in the text of the cursor.

array of object (optional) segments

List of segments and their associated types.

Properties of each object

integer start

Index of the character to start this segment at

integer end

Index of the character to end this segment after.

UnderlineStyle style

The type of the underline to modify this segment.

function (optional) callback

Called when the operation completes with a boolean indicating if the text was accepted or not. On failure, chrome.runtime.lastError is set.

If you specify the callback parameter, it should be a function that looks like this:

function(boolean success) {...};
boolean success

clearComposition

chrome.input.ime.clearComposition(object parameters, function callback)

Clear the current composition. If this extension does not own the active IME, this fails.

Parameters
object parameters
integer contextID

ID of the context where the composition will be cleared

function (optional) callback

Called when the operation completes with a boolean indicating if the text was accepted or not. On failure, chrome.runtime.lastError is set.

If you specify the callback parameter, it should be a function that looks like this:

function(boolean success) {...};
boolean success

commitText

chrome.input.ime.commitText(object parameters, function callback)

Commits the provided text to the current input.

Parameters
object parameters
integer contextID

ID of the context where the text will be committed

string text

The text to commit

function (optional) callback

Called when the operation completes with a boolean indicating if the text was accepted or not. On failure, chrome.runtime.lastError is set.

If you specify the callback parameter, it should be a function that looks like this:

function(boolean success) {...};
boolean success

sendKeyEvents

chrome.input.ime.sendKeyEvents(object parameters, function callback)

Since Chrome 33.

Sends the key events. This function is expected to be used by virtual keyboards. When key(s) on a virtual keyboard is pressed by a user, this function is used to propagate that event to the system.

Parameters
object parameters
integer contextID

ID of the context where the key events will be sent, or zero to send key events to non-input field.

array of KeyboardEvent keyData

Data on the key event.

function (optional) callback

Called when the operation completes.

If you specify the callback parameter, it should be a function that looks like this:

function() {...};

hideInputView

chrome.input.ime.hideInputView()

Since Chrome 34.

Hides the input view window, which is popped up automatically by system. If the input view window is already hidden, this function will do nothing.

setCandidateWindowProperties

chrome.input.ime.setCandidateWindowProperties(object parameters, function callback)

Sets the properties of the candidate window. This fails if the extension doesn't own the active IME

Parameters
object parameters
string engineID

ID of the engine to set properties on.

object properties
boolean (optional) visible

True to show the Candidate window, false to hide it.

boolean (optional) cursorVisible

True to show the cursor, false to hide it.

boolean (optional) vertical

True if the candidate window should be rendered vertical, false to make it horizontal.

integer (optional) pageSize

The number of candidates to display per page.

string (optional) auxiliaryText

Text that is shown at the bottom of the candidate window.

boolean (optional) auxiliaryTextVisible

True to display the auxiliary text, false to hide it.

WindowPosition (optional) windowPosition

Since Chrome 28.

Where to display the candidate window.

function (optional) callback

Called when the operation completes.

If you specify the callback parameter, it should be a function that looks like this:

function(boolean success) {...};
boolean success

setCandidates

chrome.input.ime.setCandidates(object parameters, function callback)

Sets the current candidate list. This fails if this extension doesn't own the active IME

Parameters
object parameters
integer contextID

ID of the context that owns the candidate window.

array of object candidates

List of candidates to show in the candidate window

Properties of each object

string candidate

The candidate

integer id

The candidate's id

integer (optional) parentId

The id to add these candidates under

string (optional) label

Short string displayed to next to the candidate, often the shortcut key or index

string (optional) annotation

Additional text describing the candidate

object (optional) usage

The usage or detail description of word.

string title

The title string of details description.

string body

The body string of detail description.

function (optional) callback

Called when the operation completes.

If you specify the callback parameter, it should be a function that looks like this:

function(boolean success) {...};
boolean success

setCursorPosition

chrome.input.ime.setCursorPosition(object parameters, function callback)

Set the position of the cursor in the candidate window. This is a no-op if this extension does not own the active IME.

Parameters
object parameters
integer contextID

ID of the context that owns the candidate window.

integer candidateID

ID of the candidate to select.

function (optional) callback

Called when the operation completes

If you specify the callback parameter, it should be a function that looks like this:

function(boolean success) {...};
boolean success

setMenuItems

chrome.input.ime.setMenuItems(object parameters, function callback)

Adds the provided menu items to the language menu when this IME is active.

Parameters
object parameters
string engineID

ID of the engine to use

array of MenuItem items

MenuItems to add. They will be added in the order they exist in the array.

function (optional) callback

If you specify the callback parameter, it should be a function that looks like this:

function() {...};

updateMenuItems

chrome.input.ime.updateMenuItems(object parameters, function callback)

Updates the state of the MenuItems specified

Parameters
object parameters
string engineID

ID of the engine to use

array of MenuItem items

Array of MenuItems to update

function (optional) callback

Called when the operation completes

If you specify the callback parameter, it should be a function that looks like this:

function() {...};

deleteSurroundingText

chrome.input.ime.deleteSurroundingText(object parameters, function callback)

Since Chrome 27.

Deletes the text around the caret.

Parameters
object parameters
string engineID

ID of the engine receiving the event.

integer contextID

ID of the context where the surrounding text will be deleted.

integer offset

The offset from the caret position where deletion will start. This value can be negative.

integer length

The number of characters to be deleted

function (optional) callback

Called when the operation completes.

If you specify the callback parameter, it should be a function that looks like this:

function() {...};

keyEventHandled

chrome.input.ime.keyEventHandled(string requestId, boolean response)

Since Chrome 25.

Indicates that the key event received by onKeyEvent is handled. This should only be called if the onKeyEvent listener is asynchronous.

Parameters
string requestId

Request id of the event that was handled. This should come from keyEvent.requestId

boolean response

True if the keystroke was handled, false if not

Events

onActivate

This event is sent when an IME is activated. It signals that the IME will be receiving onKeyPress events.

addListener

chrome.input.ime.onActivate.addListener(function callback)
Parameters
function callback

The callback parameter should be a function that looks like this:

function(string engineID, ScreenType screen) {...};
string engineID

ID of the engine receiving the event

ScreenType screen

Since Chrome 38.

The screen type under which the IME is activated.

onDeactivated

This event is sent when an IME is deactivated. It signals that the IME will no longer be receiving onKeyPress events.

addListener

chrome.input.ime.onDeactivated.addListener(function callback)
Parameters
function callback

The callback parameter should be a function that looks like this:

function(string engineID) {...};
string engineID

ID of the engine receiving the event

onFocus

This event is sent when focus enters a text box. It is sent to all extensions that are listening to this event, and enabled by the user.

addListener

chrome.input.ime.onFocus.addListener(function callback)
Parameters
function callback

The callback parameter should be a function that looks like this:

function( InputContext context) {...};
InputContext context

Describes the text field that has acquired focus.

onBlur

This event is sent when focus leaves a text box. It is sent to all extensions that are listening to this event, and enabled by the user.

addListener

chrome.input.ime.onBlur.addListener(function callback)
Parameters
function callback

The callback parameter should be a function that looks like this:

function(integer contextID) {...};
integer contextID

The ID of the text field that has lost focus. The ID is invalid after this call

onInputContextUpdate

This event is sent when the properties of the current InputContext change, such as the the type. It is sent to all extensions that are listening to this event, and enabled by the user.

addListener

chrome.input.ime.onInputContextUpdate.addListener(function callback)
Parameters
function callback

The callback parameter should be a function that looks like this:

function( InputContext context) {...};
InputContext context

An InputContext object describing the text field that has changed.

onKeyEvent

This event is sent if this extension owns the active IME.

addListener

chrome.input.ime.onKeyEvent.addListener(function callback)
Parameters
function callback

The callback parameter should be a function that looks like this:

function(string engineID, KeyboardEvent keyData) {...};
string engineID

ID of the engine receiving the event

KeyboardEvent keyData

Data on the key event

onCandidateClicked

This event is sent if this extension owns the active IME.

addListener

chrome.input.ime.onCandidateClicked.addListener(function callback)
Parameters
function callback

The callback parameter should be a function that looks like this:

function(string engineID, integer candidateID, MouseButton button) {...};
string engineID

ID of the engine receiving the event

integer candidateID

ID of the candidate that was clicked.

MouseButton button

Which mouse buttons was clicked.

onMenuItemActivated

Called when the user selects a menu item

addListener

chrome.input.ime.onMenuItemActivated.addListener(function callback)
Parameters
function callback

The callback parameter should be a function that looks like this:

function(string engineID, string name) {...};
string engineID

ID of the engine receiving the event

string name

Name of the MenuItem which was activated

onSurroundingTextChanged

Since Chrome 27.

Called when the editable string around caret is changed or when the caret position is moved. The text length is limited to 100 characters for each back and forth direction.

addListener

chrome.input.ime.onSurroundingTextChanged.addListener(function callback)
Parameters
function callback

The callback parameter should be a function that looks like this:

function(string engineID, object surroundingInfo) {...};
string engineID

ID of the engine receiving the event

object surroundingInfo

The surrounding information.

string text

The text around cursor.

integer focus

The ending position of the selection. This value indicates caret position if there is no selection.

integer anchor

The beginning position of the selection. This value indicates caret position if is no selection.

onReset

Since Chrome 29.

This event is sent when chrome terminates ongoing text input session.

addListener

chrome.input.ime.onReset.addListener(function callback)
Parameters
function callback

The callback parameter should be a function that looks like this:

function(string engineID) {...};
string engineID

ID of the engine receiving the event