MetaKeyKeyListener

Kotlin |Java

abstract class MetaKeyKeyListener

kotlin.Any
↳	android.text.method.MetaKeyKeyListener

Known Direct Subclasses

BaseKeyListener

Abstract base class for key listeners.

Known Indirect Subclasses

DateKeyListener, DateTimeKeyListener, DialerKeyListener, DigitsKeyListener, MultiTapKeyListener, NumberKeyListener, QwertyKeyListener, TextKeyListener, TimeKeyListener

DateKeyListener	For entering dates in a text field.
DateTimeKeyListener	For entering dates and times in the same text field.
DialerKeyListener	For dialing-only text entry
DigitsKeyListener	For digits-only text entry
MultiTapKeyListener	This is the standard key listener for alphabetic input on 12-key keyboards.
NumberKeyListener	For numeric text entry
QwertyKeyListener	This is the standard key listener for alphabetic input on qwerty keyboards.
TextKeyListener	This is the key listener for typing normal text.
TimeKeyListener	For entering times in a text field.

This base class encapsulates the behavior for tracking the state of meta keys such as SHIFT, ALT and SYM as well as the pseudo-meta state of selecting text.

Key listeners that care about meta state should inherit from this class; you should not instantiate this class directly in a client.

This class provides two mechanisms for tracking meta state that can be used together or independently.

Methods such as handleKeyDown(long,int,android.view.KeyEvent) and getMetaState(long) operate on a meta key state bit mask.
Methods such as onKeyDown(android.view.View,android.text.Editable,int,android.view.KeyEvent) and getMetaState(java.lang.CharSequence,int) operate on meta key state flags stored as spans in an Editable text buffer. The spans only describe the current meta key state of the text editor; they do not carry any positional information.

The behavior of this class varies according to the keyboard capabilities described by the KeyCharacterMap of the keyboard device such as the key modifier behavior.

MetaKeyKeyListener implements chorded and toggled key modifiers. When key modifiers are toggled into a latched or locked state, the state of the modifier is stored in the Editable text buffer or in a meta state integer managed by the client. These latched or locked modifiers should be considered to be held in addition to those that the keyboard already reported as being pressed in KeyEvent#getMetaState(). In other words, the MetaKeyKeyListener augments the meta state provided by the keyboard; it does not replace it. This distinction is important to ensure that meta keys not handled by MetaKeyKeyListener such as KeyEvent#KEYCODE_CAPS_LOCK or KeyEvent#KEYCODE_NUM_LOCK are taken into consideration.

To ensure correct meta key behavior, the following pattern should be used when mapping key codes to characters:

 private char getUnicodeChar(TextKeyListener listener, KeyEvent event, Editable textBuffer) { // Use the combined meta states from the event and the key listener. int metaState = event.getMetaState() | listener.getMetaState(textBuffer); return event.getUnicodeChar(metaState); }

Summary

Constants
static Int	`META_ALT_LOCKED` Flag that indicates that the ALT key is locked.
static Int	`META_ALT_ON` Flag that indicates that the ALT key is on.
static Int	`META_CAP_LOCKED` Flag that indicates that the SHIFT key is locked in CAPS mode.
static Int	`META_SHIFT_ON` Flag that indicates that the SHIFT key is on.
static Int	`META_SYM_LOCKED` Flag that indicates that the SYM key is locked.
static Int	`META_SYM_ON` Flag that indicates that the SYM key is on.

Public constructors
`MetaKeyKeyListener()`

Public methods
open static Unit	`adjustMetaAfterKeypress(content: Spannable!)` Call this method after you handle a keypress so that the meta state will be reset to unshifted (if it is not still down) or primed to be reset to unshifted (once it is released).
open static Long	`adjustMetaAfterKeypress(state: Long)` Call this method after you handle a keypress so that the meta state will be reset to unshifted (if it is not still down) or primed to be reset to unshifted (once it is released).
open Unit	`clearMetaKeyState(view: View!, content: Editable!, states: Int)`
open Long	`clearMetaKeyState(state: Long, which: Int)` Clears the state of the specified meta key if it is locked.
open static Unit	`clearMetaKeyState(content: Editable!, states: Int)`
static Int	`getMetaState(text: CharSequence!)` Gets the state of the meta keys.
static Int	`getMetaState(text: CharSequence!, event: KeyEvent!)` Gets the state of the meta keys for a specific key event.
static Int	`getMetaState(text: CharSequence!, meta: Int)` Gets the state of a particular meta key.
static Int	`getMetaState(text: CharSequence!, meta: Int, event: KeyEvent!)` Gets the state of a particular meta key to use with a particular key event.
static Int	`getMetaState(state: Long)` Gets the state of the meta keys.
static Int	`getMetaState(state: Long, meta: Int)` Gets the state of a particular meta key.
open static Long	`handleKeyDown(state: Long, keyCode: Int, event: KeyEvent!)` Handles presses of the meta keys.
open static Long	`handleKeyUp(state: Long, keyCode: Int, event: KeyEvent!)` Handles release of the meta keys.
open static Boolean	`isMetaTracker(text: CharSequence!, what: Any!)` Returns true if this object is one that this class would use to keep track of any meta state in the specified text.
open static Boolean	`isSelectingMetaTracker(text: CharSequence!, what: Any!)` Returns true if this object is one that this class would use to keep track of the selecting meta state in the specified text.
open Boolean	`onKeyDown(view: View!, content: Editable!, keyCode: Int, event: KeyEvent!)` Handles presses of the meta keys.
open Boolean	`onKeyUp(view: View!, content: Editable!, keyCode: Int, event: KeyEvent!)` Handles release of the meta keys.
open static Long	`resetLockedMeta(state: Long)` Call this if you are a method that ignores the locked meta state (arrow keys, for example) and you handle a key.
open static Unit	`resetMetaState(text: Spannable!)` Resets all meta state to inactive.

Protected methods
open static Unit	`resetLockedMeta(content: Spannable!)` Call this if you are a method that ignores the locked meta state (arrow keys, for example) and you handle a key.

Constants

META_ALT_LOCKED

Added in API level 1

static val META_ALT_LOCKED: Int

Flag that indicates that the ALT key is locked.

Value: 512

META_ALT_ON

Added in API level 1

static val META_ALT_ON: Int

Flag that indicates that the ALT key is on. Value equals KeyEvent#META_ALT_ON.

Value: 2

META_CAP_LOCKED

Added in API level 1

static val META_CAP_LOCKED: Int

Flag that indicates that the SHIFT key is locked in CAPS mode.

Value: 256

META_SHIFT_ON

Added in API level 1

static val META_SHIFT_ON: Int

Flag that indicates that the SHIFT key is on. Value equals KeyEvent#META_SHIFT_ON.

Value: 1

META_SYM_LOCKED

Added in API level 1

static val META_SYM_LOCKED: Int

Flag that indicates that the SYM key is locked.

Value: 1024

META_SYM_ON

Added in API level 1

static val META_SYM_ON: Int

Flag that indicates that the SYM key is on. Value equals KeyEvent#META_SYM_ON.

Value: 4

Public constructors

MetaKeyKeyListener

MetaKeyKeyListener()

Public methods

adjustMetaAfterKeypress

Added in API level 1

open static fun adjustMetaAfterKeypress(content: Spannable!): Unit

Call this method after you handle a keypress so that the meta state will be reset to unshifted (if it is not still down) or primed to be reset to unshifted (once it is released).

adjustMetaAfterKeypress

Added in API level 3

open static fun adjustMetaAfterKeypress(state: Long): Long

Call this method after you handle a keypress so that the meta state will be reset to unshifted (if it is not still down) or primed to be reset to unshifted (once it is released). Takes the current state, returns the new state.

clearMetaKeyState

Added in API level 3

open fun clearMetaKeyState(
    view: View!, 
    content: Editable!, 
    states: Int
): Unit

clearMetaKeyState

Added in API level 3

open fun clearMetaKeyState(
    state: Long, 
    which: Int
): Long

Clears the state of the specified meta key if it is locked.

Parameters
`state`	Long: the meta key state
`which`	Int: meta keys to clear, may be a combination of `META_SHIFT_ON`, `META_ALT_ON` or `META_SYM_ON`.

clearMetaKeyState

Added in API level 3

open static fun clearMetaKeyState(
    content: Editable!, 
    states: Int
): Unit

getMetaState

Added in API level 1

static fun getMetaState(text: CharSequence!): Int

Gets the state of the meta keys.

Parameters
`text`	CharSequence!: the buffer in which the meta key would have been pressed.

Return
`Int`	an integer in which each bit set to one represents a pressed or locked meta key.

getMetaState

Added in API level 19

static fun getMetaState(
    text: CharSequence!, 
    event: KeyEvent!
): Int

Gets the state of the meta keys for a specific key event. For input devices that use toggled key modifiers, the `toggled' state is stored into the text buffer. This method retrieves the meta state for this event, accounting for the stored state. If the event has been created by a device that does not support toggled key modifiers, like a virtual device for example, the stored state is ignored.

Parameters
`text`	CharSequence!: the buffer in which the meta key would have been pressed.
`event`	KeyEvent!: the event for which to evaluate the meta state.

Return
`Int`	an integer in which each bit set to one represents a pressed or locked meta key.

getMetaState

Added in API level 1

static fun getMetaState(
    text: CharSequence!, 
    meta: Int
): Int

Gets the state of a particular meta key.

Parameters
`meta`	Int: META_SHIFT_ON, META_ALT_ON, META_SYM_ON
`text`	CharSequence!: the buffer in which the meta key would have been pressed.

Return
`Int`	0 if inactive, 1 if active, 2 if locked.

getMetaState

Added in API level 19

static fun getMetaState(
    text: CharSequence!, 
    meta: Int, 
    event: KeyEvent!
): Int

Gets the state of a particular meta key to use with a particular key event. If the key event has been created by a device that does not support toggled key modifiers, like a virtual keyboard for example, only the meta state in the key event is considered.

Parameters
`meta`	Int: META_SHIFT_ON, META_ALT_ON, META_SYM_ON
`text`	CharSequence!: the buffer in which the meta key would have been pressed.
`event`	KeyEvent!: the event for which to evaluate the meta state.

Return
`Int`	0 if inactive, 1 if active, 2 if locked.

getMetaState

Added in API level 3

static fun getMetaState(state: Long): Int

Gets the state of the meta keys.

Parameters
`state`	Long: the current meta state bits.

Return
`Int`	an integer in which each bit set to one represents a pressed or locked meta key.

getMetaState

Added in API level 3

static fun getMetaState(
    state: Long, 
    meta: Int
): Int

Gets the state of a particular meta key.

Parameters
`state`	Long: the current state bits.
`meta`	Int: META_SHIFT_ON, META_ALT_ON, or META_SYM_ON

Return
`Int`	0 if inactive, 1 if active, 2 if locked.

handleKeyDown

Added in API level 3

open static fun handleKeyDown(
    state: Long, 
    keyCode: Int, 
    event: KeyEvent!
): Long

Handles presses of the meta keys.

handleKeyUp

Added in API level 3

open static fun handleKeyUp(
    state: Long, 
    keyCode: Int, 
    event: KeyEvent!
): Long

Handles release of the meta keys.

isMetaTracker

Added in API level 1

open static fun isMetaTracker(
    text: CharSequence!, 
    what: Any!
): Boolean

Returns true if this object is one that this class would use to keep track of any meta state in the specified text.

isSelectingMetaTracker

Added in API level 3

open static fun isSelectingMetaTracker(
    text: CharSequence!, 
    what: Any!
): Boolean

Returns true if this object is one that this class would use to keep track of the selecting meta state in the specified text.

onKeyDown

Added in API level 1

open fun onKeyDown(
    view: View!, 
    content: Editable!, 
    keyCode: Int, 
    event: KeyEvent!
): Boolean

Handles presses of the meta keys.

onKeyUp

Added in API level 1

open fun onKeyUp(
    view: View!, 
    content: Editable!, 
    keyCode: Int, 
    event: KeyEvent!
): Boolean

Handles release of the meta keys.

resetLockedMeta

Added in API level 3

open static fun resetLockedMeta(state: Long): Long

Call this if you are a method that ignores the locked meta state (arrow keys, for example) and you handle a key.

resetMetaState

Added in API level 1

open static fun resetMetaState(text: Spannable!): Unit

Resets all meta state to inactive.

Protected methods

resetLockedMeta

Added in API level 1

protected open static fun resetLockedMeta(content: Spannable!): Unit

Call this if you are a method that ignores the locked meta state (arrow keys, for example) and you handle a key.