KeyCharacterMap

ALPHA

public static final int ALPHA

A keyboard with all the letters, and maybe some numbers.

An alphabetic keyboard supports text entry directly but may have a condensed layout with a small form factor. In contrast to a full keyboard, some symbols may only be accessible using special on-screen character pickers. In addition, to improve typing speed and accuracy, the framework provides special affordances for alphabetic keyboards such as auto-capitalization and toggled / locked shift and alt keys.

This type of keyboard is generally designed for thumb typing.

Constant Value: 3 (0x00000003)

BUILT_IN_KEYBOARD

public static final int BUILT_IN_KEYBOARD

This constant was deprecated in API level 15.
This constant should no longer be used because there is no guarantee that a device has a built-in keyboard that can be used for typing text. There might not be a built-in keyboard, the built-in keyboard might be a NUMERIC or SPECIAL_FUNCTION keyboard, or there might be multiple keyboards installed including external keyboards. When interpreting key presses received from the framework, applications should use the device id specified in the KeyEvent received. When synthesizing key presses for delivery elsewhere or when translating key presses from unknown keyboards, applications should use the special VIRTUAL_KEYBOARD device id.

The id of the device's primary built in keyboard is always 0.

Constant Value: 0 (0x00000000)

COMBINING_ACCENT

public static final int COMBINING_ACCENT

Constant Value: -2147483648 (0x80000000)

COMBINING_ACCENT_MASK

public static final int COMBINING_ACCENT_MASK

Mask the return value from get(int, int) with this value to get a printable representation of the accent character of a "dead key."

Constant Value: 2147483647 (0x7fffffff)

FULL

public static final int FULL

A full PC-style keyboard.

A full keyboard behaves like a PC keyboard. All symbols are accessed directly by pressing keys on the keyboard without on-screen support or affordances such as auto-capitalization.

This type of keyboard is generally designed for full two hand typing.

Constant Value: 4 (0x00000004)

HEX_INPUT

public static final char HEX_INPUT

This private-use character is used to trigger Unicode character input by hex digits.

Constant Value: 61184 (0x0000ef00)

MODIFIER_BEHAVIOR_CHORDED

public static final int MODIFIER_BEHAVIOR_CHORDED

Modifier keys may be chorded with character keys.

Constant Value: 0 (0x00000000)

MODIFIER_BEHAVIOR_CHORDED_OR_TOGGLED

public static final int MODIFIER_BEHAVIOR_CHORDED_OR_TOGGLED

Modifier keys may be chorded with character keys or they may toggle into latched or locked states when pressed independently.

Constant Value: 1 (0x00000001)

NUMERIC

public static final int NUMERIC

A numeric (12-key) keyboard.

A numeric keyboard supports text entry using a multi-tap approach. It may be necessary to tap a key multiple times to generate the desired letter or symbol.

This type of keyboard is generally designed for thumb typing.

Constant Value: 1 (0x00000001)

PICKER_DIALOG_INPUT

public static final char PICKER_DIALOG_INPUT

This private-use character is used to bring up a character picker for miscellaneous symbols.

Constant Value: 61185 (0x0000ef01)

PREDICTIVE

public static final int PREDICTIVE

A keyboard with all the letters, but with more than one letter per key.

This type of keyboard is generally designed for thumb typing.

Constant Value: 2 (0x00000002)

SPECIAL_FUNCTION

public static final int SPECIAL_FUNCTION

A keyboard that is only used to control special functions rather than for typing.

A special function keyboard consists only of non-printing keys such as HOME and POWER that are not actually used for typing.

Constant Value: 5 (0x00000005)

VIRTUAL_KEYBOARD

public static final int VIRTUAL_KEYBOARD

The id of a generic virtual keyboard with a full layout that can be used to synthesize key events. Typically used with getEvents(char).

Constant Value: -1 (0xffffffff)

CREATOR

public static final Creator<KeyCharacterMap> CREATOR

describeContents

public int describeContents ()

Describe the kinds of special objects contained in this Parcelable instance's marshaled representation. For example, if the object will include a file descriptor in the output of writeToParcel(android.os.Parcel, int), the return value of this method must include the CONTENTS_FILE_DESCRIPTOR bit.

deviceHasKey

public static boolean deviceHasKey (int keyCode)

Queries the framework about whether any physical keys exist on any currently attached input devices that are capable of producing the given key code.

deviceHasKeys

public static boolean[] deviceHasKeys (int[] keyCodes)

Queries the framework about whether any physical keys exist on any currently attached input devices that are capable of producing the given array of key codes.

equals

public boolean equals (Object obj)

Indicates whether some other object is "equal to" this one.

The equals method implements an equivalence relation on non-null object references:

• It is reflexive: for any non-null reference value x, x.equals(x) should return true.
• It is symmetric: for any non-null reference values x and y, x.equals(y) should return true if and only if y.equals(x) returns true.
• It is transitive: for any non-null reference values x, y, and z, if x.equals(y) returns true and y.equals(z) returns true, then x.equals(z) should return true.
• It is consistent: for any non-null reference values x and y, multiple invocations of x.equals(y) consistently return true or consistently return false, provided no information used in equals comparisons on the objects is modified.
• For any non-null reference value x, x.equals(null) should return false.

An equivalence relation partitions the elements it operates on into equivalence classes; all the members of an equivalence class are equal to each other. Members of an equivalence class are substitutable for each other, at least for some purposes.

get

public int get (int keyCode, 
                int metaState)

Gets the Unicode character generated by the specified key and meta key state combination.

Returns the Unicode character that the specified key would produce when the specified meta bits (see MetaKeyKeyListener) were active.

Returns 0 if the key is not one that is used to type Unicode characters.

If the return value has bit COMBINING_ACCENT set, the key is a "dead key" that should be combined with another to actually produce a character -- see getDeadChar(int, int) -- after masking with COMBINING_ACCENT_MASK.

getDeadChar

public static int getDeadChar (int accent, 
                int c)

Get the character that is produced by combining the dead key producing accent with the key producing character c. For example, getDeadChar('`', 'e') returns è. getDeadChar('^', ' ') returns '^' and getDeadChar('^', '^') returns '^'.

getDisplayLabel

public char getDisplayLabel (int keyCode)

Gets the primary character for this key. In other words, the label that is physically printed on it.

getEvents

public KeyEvent[] getEvents (char[] chars)

Get an array of KeyEvent objects that if put into the input stream could plausibly generate the provided sequence of characters. It is not guaranteed that the sequence is the only way to generate these events or that it is optimal.

This function is primarily offered for instrumentation and testing purposes. It may fail to map characters to key codes. In particular, the key character map for the built-in keyboard device id may be empty. Consider using the key character map associated with the virtual keyboard device id instead.

For robust text entry, do not use this function. Instead construct a KeyEvent with action code KeyEvent#ACTION_MULTIPLE that contains the desired string using KeyEvent#KeyEvent(long, String, int, int).

getKeyData

public boolean getKeyData (int keyCode, 
                KeyCharacterMap.KeyData results)

This method was deprecated in API level 15.
instead use KeyCharacterMap#getDisplayLabel(int), KeyCharacterMap#getNumber(int) or KeyCharacterMap#get(int, int).

Get the character conversion data for a given key code.

getKeyboardType

public int getKeyboardType ()

Gets the keyboard type. Returns NUMERIC, PREDICTIVE, ALPHA, FULL or SPECIAL_FUNCTION.

Different keyboard types have different semantics. Refer to the documentation associated with the keyboard type constants for details.

getMatch

public char getMatch (int keyCode, 
                char[] chars, 
                int metaState)

Gets the first character in the character array that can be generated by the specified key code. If there are multiple choices, prefers the one that would be generated with the specified meta key modifier state.

getMatch

public char getMatch (int keyCode, 
                char[] chars)

Gets the first character in the character array that can be generated by the specified key code.

This is a convenience function that returns the same value as getMatch(keyCode, chars, 0).

getModifierBehavior

public int getModifierBehavior ()

Gets a constant that describes the behavior of this keyboard's modifier keys such as KeyEvent#KEYCODE_SHIFT_LEFT.

Currently there are two behaviors that may be combined:

• Chorded behavior: When the modifier key is pressed together with one or more character keys, the keyboard inserts the modified keys and then resets the modifier state when the modifier key is released.
• Toggled behavior: When the modifier key is pressed and released on its own it first toggles into a latched state. When latched, the modifier will apply to next character key that is pressed and will then reset itself to the initial state. If the modifier is already latched and the modifier key is pressed and release on its own again, then it toggles into a locked state. When locked, the modifier will apply to all subsequent character keys that are pressed until unlocked by pressing the modifier key on its own one more time to reset it to the initial state. Toggled behavior is useful for small profile keyboards designed for thumb typing.

This function currently returns MODIFIER_BEHAVIOR_CHORDED when the keyboard type is FULL or SPECIAL_FUNCTION and MODIFIER_BEHAVIOR_CHORDED_OR_TOGGLED otherwise. In the future, the function may also take into account global keyboard accessibility settings, other user preferences, or new device capabilities.

getNumber

public char getNumber (int keyCode)

Gets the number or symbol associated with the key.

The character value is returned, not the numeric value. If the key is not a number, but is a symbol, the symbol is retuned.

This method is intended to to support dial pads and other numeric or symbolic entry on keyboards where certain keys serve dual function as alphabetic and symbolic keys. This method returns the number or symbol associated with the key independent of whether the user has pressed the required modifier.

For example, on one particular keyboard the keys on the top QWERTY row generate numbers when ALT is pressed such that ALT-Q maps to '1'. So for that keyboard when getNumber(int) is called with KeyEvent#KEYCODE_Q it returns '1' so that the user can type numbers without pressing ALT when it makes sense.

isPrintingKey

public boolean isPrintingKey (int keyCode)

Returns true if the specified key produces a glyph.

load

public static KeyCharacterMap load (int deviceId)

Loads the key character maps for the keyboard with the specified device id.

writeToParcel

public void writeToParcel (Parcel out, 
                int flags)

Flatten this object in to a Parcel.

finalize

protected void finalize ()

Called by the garbage collector on an object when garbage collection determines that there are no more references to the object. A subclass overrides the finalize method to dispose of system resources or to perform other cleanup.

The general contract of finalize is that it is invoked if and when the Java virtual machine has determined that there is no longer any means by which this object can be accessed by any thread that has not yet died, except as a result of an action taken by the finalization of some other object or class which is ready to be finalized. The finalize method may take any action, including making this object available again to other threads; the usual purpose of finalize, however, is to perform cleanup actions before the object is irrevocably discarded. For example, the finalize method for an object that represents an input/output connection might perform explicit I/O transactions to break the connection before the object is permanently discarded.

The finalize method of class Object performs no special action; it simply returns normally. Subclasses of Object may override this definition.

The Java programming language does not guarantee which thread will invoke the finalize method for any given object. It is guaranteed, however, that the thread that invokes finalize will not be holding any user-visible synchronization locks when finalize is invoked. If an uncaught exception is thrown by the finalize method, the exception is ignored and finalization of that object terminates.

After the finalize method has been invoked for an object, no further action is taken until the Java virtual machine has again determined that there is no longer any means by which this object can be accessed by any thread that has not yet died, including possible actions by other objects or classes which are ready to be finalized, at which point the object may be discarded.

The finalize method is never invoked more than once by a Java virtual machine for any given object.

Any exception thrown by the finalize method causes the finalization of this object to be halted, but is otherwise ignored.