InputMethod

public interface InputMethod

android.view.inputmethod.InputMethod

The InputMethod interface represents an input method which can generate key events and text, such as digital, email addresses, CJK characters, other language characters, and etc., while handling various input events, and send the text back to the application that requests text input. See InputMethodManager for more general information about the architecture.

Applications will not normally use this interface themselves, instead relying on the standard interaction provided by TextView and EditText.

Those implementing input methods should normally do so by deriving from InputMethodService or one of its subclasses. When implementing an input method, the service component containing it must also supply a SERVICE_META_DATA meta-data field, referencing an XML resource providing details about the input method. All input methods also must require that clients hold the Manifest.permission.BIND_INPUT_METHOD in order to interact with the service; if this is not required, the system will not use that input method, because it can not trust that it is not compromised.

The InputMethod interface is actually split into two parts: the interface here is the top-level interface to the input method, providing all access to it, which only the system can access (due to the BIND_INPUT_METHOD permission requirement). In addition its method createSession(android.view.inputmethod.InputMethod.SessionCallback) can be called to instantate a secondary InputMethodSession interface which is what clients use to communicate with the input method.

Summary

Nested classes

interface InputMethod.SessionCallback

 

Constants

String SERVICE_INTERFACE

This is the interface name that a service implementing an input method should say that it supports -- that is, this is the action it uses for its intent filter.

String SERVICE_META_DATA

Name under which an InputMethod service component publishes information about itself.

int SHOW_EXPLICIT

Flag for showSoftInput(int, ResultReceiver): this show has been explicitly requested by the user.

int SHOW_FORCED

This constant was deprecated in API level 35. InputMethodManager#SHOW_FORCED is deprecated and should no longer be used by apps. IMEs likewise should no longer react to this flag.

Public methods

abstract void attachToken(IBinder token)

Called first thing after an input method is created, this supplies a unique token for the session it has with the system service.

abstract void bindInput(InputBinding binding)

Bind a new application environment in to the input method, so that it can later start and stop input processing.

abstract void changeInputMethodSubtype(InputMethodSubtype subtype)

Notify that the input method subtype is being changed in the same input method.

abstract void createSession(InputMethod.SessionCallback callback)

Create a new InputMethodSession that can be handed to client applications for interacting with the input method.

abstract void hideSoftInput(int flags, ResultReceiver resultReceiver)

Request that any soft input part of the input method be hidden from the user.

abstract void restartInput(InputConnection inputConnection, EditorInfo editorInfo)

This method is called when the state of this input method needs to be reset.

abstract void revokeSession(InputMethodSession session)

Disable and destroy a session that was previously created with createSession(android.view.inputmethod.InputMethod.SessionCallback).

abstract void setSessionEnabled(InputMethodSession session, boolean enabled)

Control whether a particular input method session is active.

abstract void showSoftInput(int flags, ResultReceiver resultReceiver)

Request that any soft input part of the input method be shown to the user.

abstract void startInput(InputConnection inputConnection, EditorInfo editorInfo)

This method is called when the application starts to receive text and it is ready for this input method to process received events and send result text back to the application.

abstract void unbindInput()

Unbind an application environment, called when the information previously set by bindInput(InputBinding) is no longer valid for this input method.

Constants

SERVICE_INTERFACE

Added in API level 3 
public static final String SERVICE_INTERFACE

This is the interface name that a service implementing an input method should say that it supports -- that is, this is the action it uses for its intent filter. To be supported, the service must also require the Manifest.permission.BIND_INPUT_METHOD permission so that other applications can not abuse it.

Constant Value: "android.view.InputMethod"

SERVICE_META_DATA

Added in API level 3 
public static final String SERVICE_META_DATA

Name under which an InputMethod service component publishes information about itself. This meta-data must reference an XML resource containing an <ERROR(input-method/android.R.styleable#InputMethod input-method)> tag.

Constant Value: "android.view.im"

SHOW_EXPLICIT

Added in API level 3 
public static final int SHOW_EXPLICIT

Flag for showSoftInput(int, ResultReceiver): this show has been explicitly requested by the user. If not set, the system has decided it may be a good idea to show the input method based on a navigation operation in the UI.

Constant Value: 1 (0x00000001)

SHOW_FORCED

Added in API level 3
Deprecated in API level 35 
public static final int SHOW_FORCED

This constant was deprecated in API level 35.
InputMethodManager#SHOW_FORCED is deprecated and should no longer be used by apps. IMEs likewise should no longer react to this flag.

Flag for showSoftInput(int, ResultReceiver): this show has been forced to happen by the user. If set, the input method should remain visible until deliberated dismissed by the user in its UI.

Constant Value: 2 (0x00000002)

Public methods

attachToken

Added in API level 3 
public abstract void attachToken (IBinder token)

Called first thing after an input method is created, this supplies a unique token for the session it has with the system service. It is needed to identify itself with the service to validate its operations. This token must not be passed to applications, since it grants special priviledges that should not be given to applications.

The system guarantees that this method is called back between InputMethodService#onCreate() and InputMethodService#onDestroy() at most once.
This method must be called from the main thread of your app.

Parameters
token IBinder

bindInput

Added in API level 3 
public abstract void bindInput (InputBinding binding)

Bind a new application environment in to the input method, so that it can later start and stop input processing. Typically this method is called when this input method is enabled in an application for the first time.
This method must be called from the main thread of your app.

Parameters
binding InputBinding: Information about the application window that is binding to the input method.

changeInputMethodSubtype

Added in API level 11 
public abstract void changeInputMethodSubtype (InputMethodSubtype subtype)

Notify that the input method subtype is being changed in the same input method.
This method must be called from the main thread of your app.

Parameters
subtype InputMethodSubtype: New subtype of the notified input method

createSession

Added in API level 3 
public abstract void createSession (InputMethod.SessionCallback callback)

Create a new InputMethodSession that can be handed to client applications for interacting with the input method. You can later use revokeSession(android.view.inputmethod.InputMethodSession) to destroy the session so that it can no longer be used by any clients.
This method must be called from the main thread of your app.

Parameters
callback InputMethod.SessionCallback: Interface that is called with the newly created session.

hideSoftInput

Added in API level 3 
public abstract void hideSoftInput (int flags, 
                ResultReceiver resultReceiver)

Request that any soft input part of the input method be hidden from the user.
This method must be called from the main thread of your app.

Parameters
flags int: Provides additional information about the hide request. Currently always 0.
resultReceiver ResultReceiver: The client requesting the show may wish to be told the impact of their request, which should be supplied here. The result code should be InputMethodManager.RESULT_UNCHANGED_SHOWN, InputMethodManager.RESULT_UNCHANGED_HIDDEN, InputMethodManager.RESULT_SHOWN, or InputMethodManager.RESULT_HIDDEN.

restartInput

Added in API level 3 
public abstract void restartInput (InputConnection inputConnection, 
                EditorInfo editorInfo)

This method is called when the state of this input method needs to be reset.

Typically, this method is called when the input focus is moved from one text box to another.
This method must be called from the main thread of your app.

Parameters
inputConnection InputConnection: Optional specific input connection for communicating with the text box; if null, you should use the generic bound input connection.
editorInfo EditorInfo: The attribute of the text box (typically, a EditText) that requests input.

See also:

revokeSession

Added in API level 3 
public abstract void revokeSession (InputMethodSession session)

Disable and destroy a session that was previously created with createSession(android.view.inputmethod.InputMethod.SessionCallback). After this call, the given session interface is no longer active and calls on it will fail.
This method must be called from the main thread of your app.

Parameters
session InputMethodSession: The InputMethodSession previously provided through SessionCallback.sessionCreated() that is to be revoked.

setSessionEnabled

Added in API level 3 
public abstract void setSessionEnabled (InputMethodSession session, 
                boolean enabled)

Control whether a particular input method session is active.
This method must be called from the main thread of your app.

Parameters
session InputMethodSession: The InputMethodSession previously provided through SessionCallback.sessionCreated() that is to be changed.
enabled boolean

showSoftInput

Added in API level 3 
public abstract void showSoftInput (int flags, 
                ResultReceiver resultReceiver)

Request that any soft input part of the input method be shown to the user.
This method must be called from the main thread of your app.

Parameters
flags int: Value is either 0 or a combination of SHOW_EXPLICIT, and SHOW_FORCED
resultReceiver ResultReceiver: The client requesting the show may wish to be told the impact of their request, which should be supplied here. The result code should be InputMethodManager.RESULT_UNCHANGED_SHOWN, InputMethodManager.RESULT_UNCHANGED_HIDDEN, InputMethodManager.RESULT_SHOWN, or InputMethodManager.RESULT_HIDDEN.

startInput

Added in API level 3 
public abstract void startInput (InputConnection inputConnection, 
                EditorInfo editorInfo)

This method is called when the application starts to receive text and it is ready for this input method to process received events and send result text back to the application.
This method must be called from the main thread of your app.

Parameters
inputConnection InputConnection: Optional specific input connection for communicating with the text box; if null, you should use the generic bound input connection.
editorInfo EditorInfo: Information about the text box (typically, an EditText) that requests input.

See also:

unbindInput

Added in API level 3 
public abstract void unbindInput ()

Unbind an application environment, called when the information previously set by bindInput(InputBinding) is no longer valid for this input method.

Typically this method is called when the application changes to be non-foreground.
This method must be called from the main thread of your app.