Android APIs
public class

InputMethodService

extends AbstractInputMethodService
java.lang.Object
   ↳ android.content.Context
     ↳ android.content.ContextWrapper
       ↳ android.app.Service
         ↳ android.inputmethodservice.AbstractInputMethodService
           ↳ android.inputmethodservice.InputMethodService

Class Overview

InputMethodService provides a standard implementation of an InputMethod, which final implementations can derive from and customize. See the base class AbstractInputMethodService and the InputMethod interface for more information on the basics of writing input methods.

In addition to the normal Service lifecycle methods, this class introduces some new specific callbacks that most subclasses will want to make use of:

An input method has significant discretion in how it goes about its work: the InputMethodService provides a basic framework for standard UI elements (input view, candidates view, and running in fullscreen mode), but it is up to a particular implementor to decide how to use them. For example, one input method could implement an input area with a keyboard, another could allow the user to draw text, while a third could have no input area (and thus not be visible to the user) but instead listen to audio and perform text to speech conversion.

In the implementation provided here, all of these elements are placed together in a single window managed by the InputMethodService. It will execute callbacks as it needs information about them, and provides APIs for programmatic control over them. They layout of these elements is explicitly defined:

  • The soft input view, if available, is placed at the bottom of the screen.
  • The candidates view, if currently shown, is placed above the soft input view.
  • If not running fullscreen, the application is moved or resized to be above these views; if running fullscreen, the window will completely cover the application and its top part will contain the extract text of what is currently being edited by the application.

Soft Input View

Central to most input methods is the soft input view. This is where most user interaction occurs: pressing on soft keys, drawing characters, or however else your input method wants to generate text. Most implementations will simply have their own view doing all of this work, and return a new instance of it when onCreateInputView() is called. At that point, as long as the input view is visible, you will see user interaction in that view and can call back on the InputMethodService to interact with the application as appropriate.

There are some situations where you want to decide whether or not your soft input view should be shown to the user. This is done by implementing the onEvaluateInputViewShown() to return true or false based on whether it should be shown in the current environment. If any of your state has changed that may impact this, call updateInputViewShown() to have it re-evaluated. The default implementation always shows the input view unless there is a hard keyboard available, which is the appropriate behavior for most input methods.

Candidates View

Often while the user is generating raw text, an input method wants to provide them with a list of possible interpretations of that text that can be selected for use. This is accomplished with the candidates view, and like the soft input view you implement onCreateCandidatesView() to instantiate your own view implementing your candidates UI.

Management of the candidates view is a little different than the input view, because the candidates view tends to be more transient, being shown only when there are possible candidates for the current text being entered by the user. To control whether the candidates view is shown, you use setCandidatesViewShown(boolean). Note that because the candidate view tends to be shown and hidden a lot, it does not impact the application UI in the same way as the soft input view: it will never cause application windows to resize, only cause them to be panned if needed for the user to see the current focus.

Fullscreen Mode

Sometimes your input method UI is too large to integrate with the application UI, so you just want to take over the screen. This is accomplished by switching to full-screen mode, causing the input method window to fill the entire screen and add its own "extracted text" editor showing the user the text that is being typed. Unlike the other UI elements, there is a standard implementation for the extract editor that you should not need to change. The editor is placed at the top of the IME, above the input and candidates views.

Similar to the input view, you control whether the IME is running in fullscreen mode by implementing onEvaluateFullscreenMode() to return true or false based on whether it should be fullscreen in the current environment. If any of your state has changed that may impact this, call updateFullscreenMode() to have it re-evaluated. The default implementation selects fullscreen mode when the screen is in a landscape orientation, which is appropriate behavior for most input methods that have a significant input area.

When in fullscreen mode, you have some special requirements because the user can not see the application UI. In particular, you should implement onDisplayCompletions(CompletionInfo[]) to show completions generated by your application, typically in your candidates view like you would normally show candidates.

Generating Text

The key part of an IME is of course generating text for the application. This is done through calls to the InputConnection interface to the application, which can be retrieved from getCurrentInputConnection(). This interface allows you to generate raw key events or, if the target supports it, directly edit in strings of candidates and committed text.

Information about what the target is expected and supports can be found through the EditorInfo class, which is retrieved with getCurrentInputEditorInfo() method. The most important part of this is EditorInfo.inputType; in particular, if this is EditorInfo.TYPE_NULL, then the target does not support complex edits and you need to only deliver raw key events to it. An input method will also want to look at other values here, to for example detect password mode, auto complete text views, phone number entry, etc.

When the user switches between input targets, you will receive calls to onFinishInput() and onStartInput(EditorInfo, boolean). You can use these to reset and initialize your input state for the current target. For example, you will often want to clear any input state, and update a soft keyboard to be appropriate for the new inputType.

Summary

Nested Classes
class InputMethodService.InputMethodImpl Concrete implementation of AbstractInputMethodService.AbstractInputMethodImpl that provides all of the standard behavior for an input method. 
class InputMethodService.InputMethodSessionImpl Concrete implementation of AbstractInputMethodService.AbstractInputMethodSessionImpl that provides all of the standard behavior for an input method session. 
class InputMethodService.Insets Information about where interesting parts of the input method UI appear. 
XML Attributes
Attribute Name Related Method Description
android:imeExtractEnterAnimation Animation to use when showing the fullscreen extract UI after it had previously been hidden. 
android:imeExtractExitAnimation Animation to use when hiding the fullscreen extract UI after it had previously been shown. 
android:imeFullscreenBackground Background to use for entire input method when it is being shown in fullscreen mode with the extract view, to ensure that it completely covers the application. 
Constants
int BACK_DISPOSITION_DEFAULT The back button will close the input window.
int BACK_DISPOSITION_WILL_DISMISS This input method will consume the back key.
int BACK_DISPOSITION_WILL_NOT_DISMISS This input method will not consume the back key.
[Expand]
Inherited Constants
From class android.app.Service
From class android.content.Context
From interface android.content.ComponentCallbacks2
Public Constructors
InputMethodService()
Public Methods
boolean enableHardwareAcceleration()
You can call this to try to enable hardware accelerated drawing for your IME.
int getBackDisposition()
int getCandidatesHiddenVisibility()
Returns the visibility mode (either View.INVISIBLE or View.GONE) of the candidates view when it is not shown.
InputBinding getCurrentInputBinding()
Return the currently active InputBinding for the input method, or null if there is none.
InputConnection getCurrentInputConnection()
Retrieve the currently active InputConnection that is bound to the input method, or null if there is none.
EditorInfo getCurrentInputEditorInfo()
boolean getCurrentInputStarted()
LayoutInflater getLayoutInflater()
int getMaxWidth()
Return the maximum width, in pixels, available the input method.
CharSequence getTextForImeAction(int imeOptions)
Return text that can be used as a button label for the given EditorInfo.imeOptions.
Dialog getWindow()
void hideStatusIcon()
void hideWindow()
boolean isExtractViewShown()
Return whether the fullscreen extract view is shown.
boolean isFullscreenMode()
Return whether the input method is currently running in fullscreen mode.
boolean isInputViewShown()
Return whether the soft input view is currently shown to the user.
boolean isShowInputRequested()
Returns true if we have been asked to show our input view.
void onAppPrivateCommand(String action, Bundle data)
void onBindInput()
Called when a new client has bound to the input method.
void onComputeInsets(InputMethodService.Insets outInsets)
Compute the interesting insets into your UI.
void onConfigurationChanged(Configuration newConfig)
Take care of handling configuration changes.
void onConfigureWindow(Window win, boolean isFullscreen, boolean isCandidatesOnly)
Update the given window's parameters for the given mode.
void onCreate()
Called by the system when the service is first created.
View onCreateCandidatesView()
Create and return the view hierarchy used to show candidates.
View onCreateExtractTextView()
Called by the framework to create the layout for showing extacted text.
AbstractInputMethodService.AbstractInputMethodImpl onCreateInputMethodInterface()
Implement to return our standard InputMethodService.InputMethodImpl.
AbstractInputMethodService.AbstractInputMethodSessionImpl onCreateInputMethodSessionInterface()
Implement to return our standard InputMethodService.InputMethodSessionImpl.
View onCreateInputView()
Create and return the view hierarchy used for the input area (such as a soft keyboard).
void onDestroy()
Called by the system to notify a Service that it is no longer used and is being removed.
void onDisplayCompletions(CompletionInfo[] completions)
Called when the application has reported auto-completion candidates that it would like to have the input method displayed.
boolean onEvaluateFullscreenMode()
Override this to control when the input method should run in fullscreen mode.
boolean onEvaluateInputViewShown()
Override this to control when the soft input area should be shown to the user.
boolean onExtractTextContextMenuItem(int id)
This is called when the user has selected a context menu item from the extracted text view, when running in fullscreen mode.
void onExtractedCursorMovement(int dx, int dy)
This is called when the user has performed a cursor movement in the extracted text view, when it is running in fullscreen mode.
void onExtractedSelectionChanged(int start, int end)
This is called when the user has moved the cursor in the extracted text view, when running in fullsreen mode.
void onExtractedTextClicked()
This is called when the user has clicked on the extracted text view, when running in fullscreen mode.
void onExtractingInputChanged(EditorInfo ei)
This is called when, while currently displayed in extract mode, the current input target changes.
void onFinishCandidatesView(boolean finishingInput)
Called when the candidates view is being hidden from the user.
void onFinishInput()
Called to inform the input method that text input has finished in the last editor.
void onFinishInputView(boolean finishingInput)
Called when the input view is being hidden from the user.
boolean onGenericMotionEvent(MotionEvent event)
Override this to intercept generic motion events before they are processed by the application.
void onInitializeInterface()
This is a hook that subclasses can use to perform initialization of their interface.
boolean onKeyDown(int keyCode, KeyEvent event)
Override this to intercept key down events before they are processed by the application.
boolean onKeyLongPress(int keyCode, KeyEvent event)
Default implementation of KeyEvent.Callback.onKeyLongPress(): always returns false (doesn't handle the event).
boolean onKeyMultiple(int keyCode, int count, KeyEvent event)
Override this to intercept special key multiple events before they are processed by the application.
boolean onKeyUp(int keyCode, KeyEvent event)
Override this to intercept key up events before they are processed by the application.
boolean onShowInputRequested(int flags, boolean configChange)
The system has decided that it may be time to show your input method.
void onStartCandidatesView(EditorInfo info, boolean restarting)
Called when only the candidates view has been shown for showing processing as the user enters text through a hard keyboard.
void onStartInput(EditorInfo attribute, boolean restarting)
Called to inform the input method that text input has started in an editor.
void onStartInputView(EditorInfo info, boolean restarting)
Called when the input view is being shown and input has started on a new editor.
boolean onTrackballEvent(MotionEvent event)
Override this to intercept trackball motion events before they are processed by the application.
void onUnbindInput()
Called when the previous bound client is no longer associated with the input method.
void onUpdateCursor(Rect newCursor)
Called when the application has reported a new location of its text cursor.
void onUpdateExtractedText(int token, ExtractedText text)
Called when the application has reported new extracted text to be shown due to changes in its current text state.
void onUpdateExtractingViews(EditorInfo ei)
Called when the fullscreen-mode extracting editor info has changed, to update the state of its UI such as the action buttons shown.
void onUpdateExtractingVisibility(EditorInfo ei)
Called when the fullscreen-mode extracting editor info has changed, to determine whether the extracting (extract text and candidates) portion of the UI should be shown.
void onUpdateSelection(int oldSelStart, int oldSelEnd, int newSelStart, int newSelEnd, int candidatesStart, int candidatesEnd)
Called when the application has reported a new selection region of the text.
void onViewClicked(boolean focusChanged)
Called when the user tapped or clicked a text view.
void onWindowHidden()
Called when the input method window has been hidden from the user, after previously being visible.
void onWindowShown()
Called when the input method window has been shown to the user, after previously not being visible.
void requestHideSelf(int flags)
Close this input method's soft input area, removing it from the display.
boolean sendDefaultEditorAction(boolean fromEnterKey)
Ask the input target to execute its default action via InputConnection.performEditorAction().
void sendDownUpKeyEvents(int keyEventCode)
Send the given key event code (as defined by KeyEvent) to the current input connection is a key down + key up event pair.
void sendKeyChar(char charCode)
Send the given UTF-16 character to the current input connection.
void setBackDisposition(int disposition)
void setCandidatesView(View view)
Replaces the current candidates view with a new one.
void setCandidatesViewShown(boolean shown)
Controls the visibility of the candidates display area.
void setExtractView(View view)
void setExtractViewShown(boolean shown)
Controls the visibility of the extracted text area.
void setInputView(View view)
Replaces the current input view with a new one.
void setTheme(int theme)
You can call this to customize the theme used by your IME's window.
void showStatusIcon(int iconResId)
void showWindow(boolean showInput)
void switchInputMethod(String id)
Force switch to a new input method, as identified by id.
void updateFullscreenMode()
Re-evaluate whether the input method should be running in fullscreen mode, and update its UI if this has changed since the last time it was evaluated.
void updateInputViewShown()
Re-evaluate whether the soft input area should currently be shown, and update its UI if this has changed since the last time it was evaluated.
Protected Methods
void dump(FileDescriptor fd, PrintWriter fout, String[] args)
Performs a dump of the InputMethodService's internal state.
void onCurrentInputMethodSubtypeChanged(InputMethodSubtype newSubtype)
Called when the subtype was changed.
[Expand]
Inherited Methods
From class android.inputmethodservice.AbstractInputMethodService
From class android.app.Service
From class android.content.ContextWrapper
From class android.content.Context
From class java.lang.Object
From interface android.content.ComponentCallbacks
From interface android.content.ComponentCallbacks2
From interface android.view.KeyEvent.Callback

XML Attributes

android:imeExtractEnterAnimation

Animation to use when showing the fullscreen extract UI after it had previously been hidden.

Must be a reference to another resource, in the form "@[+][package:]type:name" or to a theme attribute in the form "?[package:][type:]name".

This corresponds to the global attribute resource symbol imeExtractEnterAnimation.

Related Methods

android:imeExtractExitAnimation

Animation to use when hiding the fullscreen extract UI after it had previously been shown.

Must be a reference to another resource, in the form "@[+][package:]type:name" or to a theme attribute in the form "?[package:][type:]name".

This corresponds to the global attribute resource symbol imeExtractExitAnimation.

Related Methods

android:imeFullscreenBackground

Background to use for entire input method when it is being shown in fullscreen mode with the extract view, to ensure that it completely covers the application. This allows, for example, the candidate view to be hidden while in fullscreen mode without having the application show through behind it.

May be a reference to another resource, in the form "@[+][package:]type:name" or to a theme attribute in the form "?[package:][type:]name".

May be a color value, in the form of "#rgb", "#argb", "#rrggbb", or "#aarrggbb".

This corresponds to the global attribute resource symbol imeFullscreenBackground.

Related Methods

Constants

public static final int BACK_DISPOSITION_DEFAULT

Added in API level 11

The back button will close the input window.

Constant Value: 0 (0x00000000)

public static final int BACK_DISPOSITION_WILL_DISMISS

Added in API level 11

This input method will consume the back key.

Constant Value: 2 (0x00000002)

public static final int BACK_DISPOSITION_WILL_NOT_DISMISS

Added in API level 11

This input method will not consume the back key.

Constant Value: 1 (0x00000001)

Public Constructors

public InputMethodService ()

Added in API level 3

Public Methods

public boolean enableHardwareAcceleration ()

Added in API level 17

You can call this to try to enable hardware accelerated drawing for your IME. This must be set before onCreate(), so you will typically call it in your constructor. It is not always possible to use hardware acclerated drawing in an IME (for example on low-end devices that do not have the resources to support this), so the call returns true if it succeeds otherwise false if you will need to draw in software. You must be able to handle either case.

public int getBackDisposition ()

Added in API level 11

public int getCandidatesHiddenVisibility ()

Added in API level 3

Returns the visibility mode (either View.INVISIBLE or View.GONE) of the candidates view when it is not shown. The default implementation returns GONE when isExtractViewShown() returns true, otherwise VISIBLE. Be careful if you change this to return GONE in other situations -- if showing or hiding the candidates view causes your window to resize, this can cause temporary drawing artifacts as the resize takes place.

public InputBinding getCurrentInputBinding ()

Added in API level 3

Return the currently active InputBinding for the input method, or null if there is none.

public InputConnection getCurrentInputConnection ()

Added in API level 3

Retrieve the currently active InputConnection that is bound to the input method, or null if there is none.

public EditorInfo getCurrentInputEditorInfo ()

Added in API level 3

public boolean getCurrentInputStarted ()

Added in API level 3

public LayoutInflater getLayoutInflater ()

Added in API level 3

public int getMaxWidth ()

Added in API level 3

Return the maximum width, in pixels, available the input method. Input methods are positioned at the bottom of the screen and, unless running in fullscreen, will generally want to be as short as possible so should compute their height based on their contents. However, they can stretch as much as needed horizontally. The function returns to you the maximum amount of space available horizontally, which you can use if needed for UI placement.

In many cases this is not needed, you can just rely on the normal view layout mechanisms to position your views within the full horizontal space given to the input method.

Note that this value can change dynamically, in particular when the screen orientation changes.

public CharSequence getTextForImeAction (int imeOptions)

Added in API level 3

Return text that can be used as a button label for the given EditorInfo.imeOptions. Returns null if there is no action requested. Note that there is no guarantee that the returned text will be relatively short, so you probably do not want to use it as text on a soft keyboard key label.

Parameters
imeOptions The value from @link EditorInfo#imeOptions EditorInfo.imeOptions}.
Returns
  • Returns a label to use, or null if there is no action.

public Dialog getWindow ()

Added in API level 3

public void hideStatusIcon ()

Added in API level 3

public void hideWindow ()

Added in API level 3

public boolean isExtractViewShown ()

Added in API level 3

Return whether the fullscreen extract view is shown. This will only return true if isFullscreenMode() returns true, and in that case its value depends on the last call to setExtractViewShown(boolean). This effectively lets you determine if the application window is entirely covered (when this returns true) or if some part of it may be shown (if this returns false, though if isFullscreenMode() returns true in that case then it is probably only a sliver of the application).

public boolean isFullscreenMode ()

Added in API level 3

Return whether the input method is currently running in fullscreen mode. This is the mode that was last determined and applied by updateFullscreenMode().

public boolean isInputViewShown ()

Added in API level 3

Return whether the soft input view is currently shown to the user. This is the state that was last determined and applied by updateInputViewShown().

public boolean isShowInputRequested ()

Added in API level 3

Returns true if we have been asked to show our input view.

public void onAppPrivateCommand (String action, Bundle data)

Added in API level 3

public void onBindInput ()

Added in API level 3

Called when a new client has bound to the input method. This may be followed by a series of onStartInput(EditorInfo, boolean) and onFinishInput() calls as the user navigates through its UI. Upon this call you know that getCurrentInputBinding() and getCurrentInputConnection() return valid objects.

public void onComputeInsets (InputMethodService.Insets outInsets)

Added in API level 3

Compute the interesting insets into your UI. The default implementation uses the top of the candidates frame for the visible insets, and the top of the input frame for the content insets. The default touchable insets are TOUCHABLE_INSETS_VISIBLE.

Note that this method is not called when isExtractViewShown() returns true, since in that case the application is left as-is behind the input method and not impacted by anything in its UI.

Parameters
outInsets Fill in with the current UI insets.

public void onConfigurationChanged (Configuration newConfig)

Added in API level 3

Take care of handling configuration changes. Subclasses of InputMethodService generally don't need to deal directly with this on their own; the standard implementation here takes care of regenerating the input method UI as a result of the configuration change, so you can rely on your onCreateInputView() and other methods being called as appropriate due to a configuration change.

When a configuration change does happen, onInitializeInterface() is guaranteed to be called the next time prior to any of the other input or UI creation callbacks. The following will be called immediately depending if appropriate for current state: onStartInput(EditorInfo, boolean) if input is active, and onCreateInputView() and onStartInputView(EditorInfo, boolean) and related appropriate functions if the UI is displayed.

Parameters
newConfig The new device configuration.

public void onConfigureWindow (Window win, boolean isFullscreen, boolean isCandidatesOnly)

Added in API level 3

Update the given window's parameters for the given mode. This is called when the window is first displayed and each time the fullscreen or candidates only mode changes.

The default implementation makes the layout for the window MATCH_PARENT x MATCH_PARENT when in fullscreen mode, and MATCH_PARENT x WRAP_CONTENT when in non-fullscreen mode.

Parameters
win The input method's window.
isFullscreen If true, the window is running in fullscreen mode and intended to cover the entire application display.
isCandidatesOnly If true, the window is only showing the candidates view and none of the rest of its UI. This is mutually exclusive with fullscreen mode.

public void onCreate ()

Added in API level 3

Called by the system when the service is first created. Do not call this method directly.

public View onCreateCandidatesView ()

Added in API level 3

Create and return the view hierarchy used to show candidates. This will be called once, when the candidates are first displayed. You can return null to have no candidates view; the default implementation returns null.

To control when the candidates view is displayed, use setCandidatesViewShown(boolean). To change the candidates view after the first one is created by this function, use setCandidatesView(View).

public View onCreateExtractTextView ()

Added in API level 3

Called by the framework to create the layout for showing extacted text. Only called when in fullscreen mode. The returned view hierarchy must have an ExtractEditText whose ID is inputExtractEditText.

public AbstractInputMethodService.AbstractInputMethodImpl onCreateInputMethodInterface ()

Added in API level 3

Implement to return our standard InputMethodService.InputMethodImpl. Subclasses can override to provide their own customized version.

public AbstractInputMethodService.AbstractInputMethodSessionImpl onCreateInputMethodSessionInterface ()

Added in API level 3

Implement to return our standard InputMethodService.InputMethodSessionImpl. Subclasses can override to provide their own customized version.

public View onCreateInputView ()

Added in API level 3

Create and return the view hierarchy used for the input area (such as a soft keyboard). This will be called once, when the input area is first displayed. You can return null to have no input area; the default implementation returns null.

To control when the input view is displayed, implement onEvaluateInputViewShown(). To change the input view after the first one is created by this function, use setInputView(View).

public void onDestroy ()

Added in API level 3

Called by the system to notify a Service that it is no longer used and is being removed. The service should clean up any resources it holds (threads, registered receivers, etc) at this point. Upon return, there will be no more calls in to this Service object and it is effectively dead. Do not call this method directly.

public void onDisplayCompletions (CompletionInfo[] completions)

Added in API level 3

Called when the application has reported auto-completion candidates that it would like to have the input method displayed. Typically these are only used when an input method is running in full-screen mode, since otherwise the user can see and interact with the pop-up window of completions shown by the application.

The default implementation here does nothing.

public boolean onEvaluateFullscreenMode ()

Added in API level 3

Override this to control when the input method should run in fullscreen mode. The default implementation runs in fullsceen only when the screen is in landscape mode. If you change what this returns, you will need to call updateFullscreenMode() yourself whenever the returned value may have changed to have it re-evaluated and applied.

public boolean onEvaluateInputViewShown ()

Added in API level 3

Override this to control when the soft input area should be shown to the user. The default implementation only shows the input view when there is no hard keyboard or the keyboard is hidden. If you change what this returns, you will need to call updateInputViewShown() yourself whenever the returned value may have changed to have it re-evaluated and applied.

public boolean onExtractTextContextMenuItem (int id)

Added in API level 3

This is called when the user has selected a context menu item from the extracted text view, when running in fullscreen mode. The default implementation sends this action to the current InputConnection's performContextMenuAction(int), for it to be processed in underlying "real" editor. Re-implement this to provide whatever behavior you want.

public void onExtractedCursorMovement (int dx, int dy)

Added in API level 3

This is called when the user has performed a cursor movement in the extracted text view, when it is running in fullscreen mode. The default implementation hides the candidates view when a vertical movement happens, but only if the extracted text editor has a vertical scroll bar because its text doesn't fit. Re-implement this to provide whatever behavior you want.

Parameters
dx The amount of cursor movement in the x dimension.
dy The amount of cursor movement in the y dimension.

public void onExtractedSelectionChanged (int start, int end)

Added in API level 3

This is called when the user has moved the cursor in the extracted text view, when running in fullsreen mode. The default implementation performs the corresponding selection change on the underlying text editor.

public void onExtractedTextClicked ()

Added in API level 3

This is called when the user has clicked on the extracted text view, when running in fullscreen mode. The default implementation hides the candidates view when this happens, but only if the extracted text editor has a vertical scroll bar because its text doesn't fit. Re-implement this to provide whatever behavior you want.

public void onExtractingInputChanged (EditorInfo ei)

Added in API level 3

This is called when, while currently displayed in extract mode, the current input target changes. The default implementation will auto-hide the IME if the new target is not a full editor, since this can be a confusing experience for the user.

public void onFinishCandidatesView (boolean finishingInput)

Added in API level 3

Called when the candidates view is being hidden from the user. This will be called either prior to hiding the window, or prior to switching to another target for editing.

The default implementation uses the InputConnection to clear any active composing text; you can override this (not calling the base class implementation) to perform whatever behavior you would like.

Parameters
finishingInput If true, onFinishInput() will be called immediately after.

public void onFinishInput ()

Added in API level 3

Called to inform the input method that text input has finished in the last editor. At this point there may be a call to onStartInput(EditorInfo, boolean) to perform input in a new editor, or the input method may be left idle. This method is not called when input restarts in the same editor.

The default implementation uses the InputConnection to clear any active composing text; you can override this (not calling the base class implementation) to perform whatever behavior you would like.

public void onFinishInputView (boolean finishingInput)

Added in API level 3

Called when the input view is being hidden from the user. This will be called either prior to hiding the window, or prior to switching to another target for editing.

The default implementation uses the InputConnection to clear any active composing text; you can override this (not calling the base class implementation) to perform whatever behavior you would like.

Parameters
finishingInput If true, onFinishInput() will be called immediately after.

public boolean onGenericMotionEvent (MotionEvent event)

Added in API level 17

Override this to intercept generic motion events before they are processed by the application. If you return true, the application will not itself process the event. If you return false, the normal application processing will occur as if the IME had not seen the event at all.

Parameters
event The motion event being received.
Returns
  • True if the event was handled in this function, false otherwise.

public void onInitializeInterface ()

Added in API level 3

This is a hook that subclasses can use to perform initialization of their interface. It is called for you prior to any of your UI objects being created, both after the service is first created and after a configuration change happens.

public boolean onKeyDown (int keyCode, KeyEvent event)

Added in API level 3

Override this to intercept key down events before they are processed by the application. If you return true, the application will not process the event itself. If you return false, the normal application processing will occur as if the IME had not seen the event at all.

The default implementation intercepts KeyEvent.KEYCODE_BACK if the IME is currently shown, to possibly hide it when the key goes up (if not canceled or long pressed). In addition, in fullscreen mode only, it will consume DPAD movement events to move the cursor in the extracted text view, not allowing them to perform navigation in the underlying application.

public boolean onKeyLongPress (int keyCode, KeyEvent event)

Added in API level 5

Default implementation of KeyEvent.Callback.onKeyLongPress(): always returns false (doesn't handle the event).

public boolean onKeyMultiple (int keyCode, int count, KeyEvent event)

Added in API level 3

Override this to intercept special key multiple events before they are processed by the application. If you return true, the application will not itself process the event. If you return false, the normal application processing will occur as if the IME had not seen the event at all.

The default implementation always returns false, except when in fullscreen mode, where it will consume DPAD movement events to move the cursor in the extracted text view, not allowing them to perform navigation in the underlying application.

public boolean onKeyUp (int keyCode, KeyEvent event)

Added in API level 3

Override this to intercept key up events before they are processed by the application. If you return true, the application will not itself process the event. If you return false, the normal application processing will occur as if the IME had not seen the event at all.

The default implementation intercepts KeyEvent.KEYCODE_BACK to hide the current IME UI if it is shown. In addition, in fullscreen mode only, it will consume DPAD movement events to move the cursor in the extracted text view, not allowing them to perform navigation in the underlying application.

public boolean onShowInputRequested (int flags, boolean configChange)

Added in API level 3

The system has decided that it may be time to show your input method. This is called due to a corresponding call to your InputMethod.showSoftInput() method. The default implementation uses onEvaluateInputViewShown(), onEvaluateFullscreenMode(), and the current configuration to decide whether the input view should be shown at this point.

Parameters
flags Provides additional information about the show request, as per InputMethod.showSoftInput().
configChange This is true if we are re-showing due to a configuration change.
Returns
  • Returns true to indicate that the window should be shown.

public void onStartCandidatesView (EditorInfo info, boolean restarting)

Added in API level 3

Called when only the candidates view has been shown for showing processing as the user enters text through a hard keyboard. This will always be called after onStartInput(EditorInfo, boolean), allowing you to do your general setup there and just view-specific setup here. You are guaranteed that onCreateCandidatesView() will have been called some time before this function is called.

Note that this will not be called when the input method is running in full editing mode, and thus receiving onStartInputView(EditorInfo, boolean) to initiate that operation. This is only for the case when candidates are being shown while the input method editor is hidden but wants to show its candidates UI as text is entered through some other mechanism.

Parameters
info Description of the type of text being edited.
restarting Set to true if we are restarting input on the same text field as before.

public void onStartInput (EditorInfo attribute, boolean restarting)

Added in API level 3

Called to inform the input method that text input has started in an editor. You should use this callback to initialize the state of your input to match the state of the editor given to it.

Parameters
attribute The attributes of the editor that input is starting in.
restarting Set to true if input is restarting in the same editor such as because the application has changed the text in the editor. Otherwise will be false, indicating this is a new session with the editor.

public void onStartInputView (EditorInfo info, boolean restarting)

Added in API level 3

Called when the input view is being shown and input has started on a new editor. This will always be called after onStartInput(EditorInfo, boolean), allowing you to do your general setup there and just view-specific setup here. You are guaranteed that onCreateInputView() will have been called some time before this function is called.

Parameters
info Description of the type of text being edited.
restarting Set to true if we are restarting input on the same text field as before.

public boolean onTrackballEvent (MotionEvent event)

Added in API level 3

Override this to intercept trackball motion events before they are processed by the application. If you return true, the application will not itself process the event. If you return false, the normal application processing will occur as if the IME had not seen the event at all.

Parameters
event The motion event being received.
Returns
  • True if the event was handled in this function, false otherwise.

public void onUnbindInput ()

Added in API level 3

Called when the previous bound client is no longer associated with the input method. After returning getCurrentInputBinding() and getCurrentInputConnection() will no longer return valid objects.

public void onUpdateCursor (Rect newCursor)

Added in API level 3

Called when the application has reported a new location of its text cursor. This is only called if explicitly requested by the input method. The default implementation does nothing.

public void onUpdateExtractedText (int token, ExtractedText text)

Added in API level 3

Called when the application has reported new extracted text to be shown due to changes in its current text state. The default implementation here places the new text in the extract edit text, when the input method is running in fullscreen mode.

public void onUpdateExtractingViews (EditorInfo ei)

Added in API level 3

Called when the fullscreen-mode extracting editor info has changed, to update the state of its UI such as the action buttons shown. You do not need to deal with this if you are using the standard full screen extract UI. If replacing it, you will need to re-implement this to put the appropriate action button in your own UI and handle it, and perform any other changes.

The standard implementation turns on or off its accessory area depending on whether there is an action button, and hides or shows the entire extract area depending on whether it makes sense for the current editor. In particular, a TYPE_NULL or TYPE_TEXT_VARIATION_FILTER input type will turn off the extract area since there is no text to be shown.

public void onUpdateExtractingVisibility (EditorInfo ei)

Added in API level 3

Called when the fullscreen-mode extracting editor info has changed, to determine whether the extracting (extract text and candidates) portion of the UI should be shown. The standard implementation hides or shows the extract area depending on whether it makes sense for the current editor. In particular, a TYPE_NULL input type or IME_FLAG_NO_EXTRACT_UI flag will turn off the extract area since there is no text to be shown.

public void onUpdateSelection (int oldSelStart, int oldSelEnd, int newSelStart, int newSelEnd, int candidatesStart, int candidatesEnd)

Added in API level 3

Called when the application has reported a new selection region of the text. This is called whether or not the input method has requested extracted text updates, although if so it will not receive this call if the extracted text has changed as well.

Be careful about changing the text in reaction to this call with methods such as setComposingText, commitText or deleteSurroundingText. If the cursor moves as a result, this method will be called again, which may result in an infinite loop.

The default implementation takes care of updating the cursor in the extract text, if it is being shown.

public void onViewClicked (boolean focusChanged)

Added in API level 14

Called when the user tapped or clicked a text view. IMEs can't rely on this method being called because this was not part of the original IME protocol, so applications with custom text editing written before this method appeared will not call to inform the IME of this interaction.

Parameters
focusChanged true if the user changed the focused view by this click.

public void onWindowHidden ()

Added in API level 3

Called when the input method window has been hidden from the user, after previously being visible.

public void onWindowShown ()

Added in API level 3

Called when the input method window has been shown to the user, after previously not being visible. This is done after all of the UI setup for the window has occurred (creating its views etc).

public void requestHideSelf (int flags)

Added in API level 3

Close this input method's soft input area, removing it from the display. The input method will continue running, but the user can no longer use it to generate input by touching the screen.

Parameters
flags Provides additional operating flags. Currently may be 0 or have the InputMethodManager.HIDE_IMPLICIT_ONLY bit set.

public boolean sendDefaultEditorAction (boolean fromEnterKey)

Added in API level 3

Ask the input target to execute its default action via InputConnection.performEditorAction().

Parameters
fromEnterKey If true, this will be executed as if the user had pressed an enter key on the keyboard, that is it will not be done if the editor has set EditorInfo.IME_FLAG_NO_ENTER_ACTION. If false, the action will be sent regardless of how the editor has set that flag.
Returns
  • Returns a boolean indicating whether an action has been sent. If false, either the editor did not specify a default action or it does not want an action from the enter key. If true, the action was sent (or there was no input connection at all).

public void sendDownUpKeyEvents (int keyEventCode)

Added in API level 3

Send the given key event code (as defined by KeyEvent) to the current input connection is a key down + key up event pair. The sent events have KeyEvent.FLAG_SOFT_KEYBOARD set, so that the recipient can identify them as coming from a software input method, and KeyEvent.FLAG_KEEP_TOUCH_MODE, so that they don't impact the current touch mode of the UI.

Note that it's discouraged to send such key events in normal operation; this is mainly for use with TYPE_NULL type text fields, or for non-rich input methods. A reasonably capable software input method should use the commitText(CharSequence, int) family of methods to send text to an application, rather than sending key events.

Parameters
keyEventCode The raw key code to send, as defined by KeyEvent.

public void sendKeyChar (char charCode)

Added in API level 3

Send the given UTF-16 character to the current input connection. Most characters will be delivered simply by calling InputConnection.commitText() with the character; some, however, may be handled different. In particular, the enter character ('\n') will either be delivered as an action code or a raw key event, as appropriate. Consider this as a convenience method for IMEs that do not have a full implementation of actions; a fully complying IME will decide of the right action for each event and will likely never call this method except maybe to handle events coming from an actual hardware keyboard.

Parameters
charCode The UTF-16 character code to send.

public void setBackDisposition (int disposition)

Added in API level 11

public void setCandidatesView (View view)

Added in API level 3

Replaces the current candidates view with a new one. You only need to call this when dynamically changing the view; normally, you should implement onCreateCandidatesView() and create your view when first needed by the input method.

public void setCandidatesViewShown (boolean shown)

Added in API level 3

Controls the visibility of the candidates display area. By default it is hidden.

public void setExtractView (View view)

Added in API level 3

public void setExtractViewShown (boolean shown)

Added in API level 3

Controls the visibility of the extracted text area. This only applies when the input method is in fullscreen mode, and thus showing extracted text. When false, the extracted text will not be shown, allowing some of the application to be seen behind. This is normally set for you by onUpdateExtractingVisibility(EditorInfo). This controls the visibility of both the extracted text and candidate view; the latter since it is not useful if there is no text to see.

public void setInputView (View view)

Added in API level 3

Replaces the current input view with a new one. You only need to call this when dynamically changing the view; normally, you should implement onCreateInputView() and create your view when first needed by the input method.

public void setTheme (int theme)

Added in API level 3

You can call this to customize the theme used by your IME's window. This theme should typically be one that derives from Theme_InputMethod, which is the default theme you will get. This must be set before onCreate(), so you will typically call it in your constructor with the resource ID of your custom theme.

Parameters
theme The style resource describing the theme.

public void showStatusIcon (int iconResId)

Added in API level 3

public void showWindow (boolean showInput)

Added in API level 3

public void switchInputMethod (String id)

Added in API level 3

Force switch to a new input method, as identified by id. This input method will be destroyed, and the requested one started on the current input field.

Parameters
id Unique identifier of the new input method ot start.

public void updateFullscreenMode ()

Added in API level 3

Re-evaluate whether the input method should be running in fullscreen mode, and update its UI if this has changed since the last time it was evaluated. This will call onEvaluateFullscreenMode() to determine whether it should currently run in fullscreen mode. You can use isFullscreenMode() to determine if the input method is currently running in fullscreen mode.

public void updateInputViewShown ()

Added in API level 3

Re-evaluate whether the soft input area should currently be shown, and update its UI if this has changed since the last time it was evaluated. This will call onEvaluateInputViewShown() to determine whether the input view should currently be shown. You can use isInputViewShown() to determine if the input view is currently shown.

Protected Methods

protected void dump (FileDescriptor fd, PrintWriter fout, String[] args)

Added in API level 3

Performs a dump of the InputMethodService's internal state. Override to add your own information to the dump.

Parameters
fd The raw file descriptor that the dump is being sent to.
fout The PrintWriter to which you should dump your state. This will be closed for you after you return.
args additional arguments to the dump request.

protected void onCurrentInputMethodSubtypeChanged (InputMethodSubtype newSubtype)

Added in API level 11

Called when the subtype was changed.

Parameters
newSubtype the subtype which is being changed to.