Defines the interface for an input method that supports complex text input.
Input methods traditionally support text input for languages that have
more characters than can be represented on a standard-size keyboard,
such as Chinese, Japanese, and Korean. However, they may also be used to
support phonetic text input for English or character reordering for Thai.
Subclasses of InputMethod can be loaded by the input method framework; they
can then be selected either through the API
(InputContext.selectInputMethod
)
or the user interface (the input method selection menu).
Activates the input method for immediate input processing.
If an input method provides its own windows, it should make sure
at this point that all necessary windows are open and visible.
This method is called
The method is only called when the input method is inactive.
A newly instantiated input method is assumed to be inactive.
Deactivates the input method.
The isTemporary argument has the same meaning as in
FocusEvent.isTemporary
.
If an input method provides its own windows, only windows that relate
to the current composition (such as a lookup choice window) should be
closed at this point.
It is possible that the input method will be immediately activated again
for a different client component, and closing and reopening more
persistent windows (such as a control panel) would create unnecessary
screen flicker.
Before an instance of a different input method class is activated,
#hideWindows
is called on the current input method.
This method is called
The method is only called when the input method is active.
Dispatches the event to the input method. If input method support is
enabled for the focussed component, incoming events of certain types
are dispatched to the current input method for this component before
they are dispatched to the component's methods or event listeners.
The input method decides whether it needs to handle the event. If it
does, it also calls the event's
consume
method; this
causes the event to not get dispatched to the component's event
processing methods or event listeners.
Events are dispatched if they are instances of InputEvent or its
subclasses.
This includes instances of the AWT classes KeyEvent and MouseEvent.
This method is called by InputContext.dispatchEvent
.
Disposes of the input method and releases the resources used by it.
In particular, the input method should dispose windows and close files that are no
longer needed.
This method is called by InputContext.dispose
.
The method is only called when the input method is inactive.
No method of this interface is called on this instance after dispose.
Ends any input composition that may currently be going on in this
context. Depending on the platform and possibly user preferences,
this may commit or delete uncommitted text. Any changes to the text
are communicated to the active component using an input method event.
A text editing component may call this in a variety of situations,
for example, when the user moves the insertion point within the text
(but outside the composed text), or when the component's text is
saved to a file or copied to the clipboard.
This method is called
Returns a control object from this input method, or null. A
control object provides methods that control the behavior of the
input method or obtain information from the input method. The type
of the object is an input method specific class. Clients have to
compare the result against known input method control object
classes and cast to the appropriate class to invoke the methods
provided.
This method is called by
InputContext.getInputMethodControlObject
.
Returns the current input locale. Might return null in exceptional cases.
This method is called
- by InputContext.getLocale
and
- when switching from this input method to a different one through the
user interface.
Closes or hides all windows opened by this input method instance or
its class.
This method is called
- before calling activate
on an instance of a different input
method class,
- before calling dispose
on this input method.
The method is only called when the input method is inactive.
Determines whether this input method is enabled.
An input method that is enabled for composition interprets incoming
events for both composition and control purposes, while a
disabled input method does not interpret events for composition.
This method is called
Notifies this input method of changes in the client window
location or state. This method is called while this input
method is the current input method of its input context and
notifications for it are enabled (see
InputMethodContext.enableClientWindowNotification
). Calls
to this method are temporarily suspended if the input context's
removeNotify
method is called, and resume when the input method is activated
for a new client component. It is called in the following
situations:
-
when the window containing the current client component changes
in location, size, visibility, iconification state, or when the
window is closed.
-
from
enableClientWindowNotification(inputMethod,
true)
if the current client component exists,
-
when activating the input method for the first time after it
called
enableClientWindowNotification(inputMethod,
true)
if during the call no current client component was
available,
-
when activating the input method for a new client component
after the input context's removeNotify method has been
called.
Starts the reconversion operation. The input method obtains the
text to be reconverted from the current client component using the
InputMethodRequests.getSelectedText
method. It can use other
InputMethodRequests
methods to request additional information required for the
reconversion operation. The composed and committed text
produced by the operation is sent to the client component as a
sequence of
InputMethodEvent
s. If the given text
cannot be reconverted, the same text should be sent to the
client component as committed text.
This method is called by
InputContext.reconvert
.
Notifies the input method that a client component has been
removed from its containment hierarchy, or that input method
support has been disabled for the component.
This method is called by InputContext.removeNotify
.
The method is only called when the input method is inactive.
Sets the subsets of the Unicode character set that this input method
is allowed to input. Null may be passed in to indicate that all
characters are allowed.
This method is called
Enables or disables this input method for composition,
depending on the value of the parameter
enable
.
An input method that is enabled for composition interprets incoming
events for both composition and control purposes, while a
disabled input method does not interpret events for composition.
Note however that events are passed on to the input method regardless
whether it is enabled or not, and that an input method that is disabled
for composition may still interpret events for control purposes,
including to enable or disable itself for composition.
For input methods provided by host operating systems, it is not always possible to
determine whether this operation is supported. For example, an input method may enable
composition only for some locales, and do nothing for other locales. For such input
methods, it is possible that this method does not throw
UnsupportedOperationException
,
but also does not affect whether composition is enabled.
This method is called
Sets the input method context, which is used to dispatch input method
events to the client component and to request information from
the client component.
This method is called once immediately after instantiating this input
method.
Attempts to set the input locale. If the input method supports the
desired locale, it changes its behavior to support input for the locale
and returns true.
Otherwise, it returns false and does not change its behavior.
This method is called
- by InputContext.selectInputMethod
,
- when switching to this input method through the user interface if the user
specified a locale or if the previously selected input method's
getLocale
method
returns a non-null value.