javax.microedition.lcdui
Interface KeyListener

public interface KeyListener

Classes implementing this interface provide methods that are called when user of the device will generate key events, for example, pressing the keys available in a system keypad or keyboard. When a key is pressed, held down or released, the appropriate method will be invoked. The methods have following parameters:

• keyCode: keyCodes often represent the character of the key that was typed. This is the final character that results after all modifiers have been applied. The keyCode values are the same that are used and defined for key event delivery methods of Canvas.
• keyModifier: carries the key modifier (Alt, Shift, Ctrl, Chr etc.) information. Modifier keys are only available in some devices, especially those with full keyboards.
The KeyListener may be set with Canvas.setKeyListener() method and CustomItem.setKeyListener().

Since:

MIDP 3.0

Field Summary

static int	MODIFIER_ALT Key modifier mask indicating the Alt key.
static int	MODIFIER_CHR Key modifier mask indicating the Chr key.
static int	MODIFIER_COMMAND Key modifier mask indicating the Command key.
static int	MODIFIER_CTRL Key modifier mask indicating the Control / Ctrl key.
static int	MODIFIER_MASK A bitmask for all key modifiers.
static int	MODIFIER_SHIFT Key modifier mask indicating the SHIFT key.

Method Summary

void	keyPressed(int keyCode, int keyModifier) Called when a key is pressed.
void	keyReleased(int keyCode, int keyModifier) Called when a key is released.
void	keyRepeated(int keyCode, int keyModifier) Called when a key is repeated (held down).

Field Detail

MODIFIER_ALT

static final int MODIFIER_ALT

Key modifier mask indicating the Alt key.

See Also:

Constant Field Values

MODIFIER_SHIFT

static final int MODIFIER_SHIFT

Key modifier mask indicating the SHIFT key.

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Constant Field Values

MODIFIER_CTRL

static final int MODIFIER_CTRL

Key modifier mask indicating the Control / Ctrl key.

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Constant Field Values

MODIFIER_COMMAND

static final int MODIFIER_COMMAND

Key modifier mask indicating the Command key.

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Constant Field Values

MODIFIER_CHR

static final int MODIFIER_CHR

Key modifier mask indicating the Chr key.

See Also:

Constant Field Values

MODIFIER_MASK

static final int MODIFIER_MASK

A bitmask for all key modifiers. Not initialized in the declaration to stop the compiler from inlining the value.

See Also:

Constant Field Values

Method Detail

keyPressed

void keyPressed(int keyCode,
                int keyModifier)

Called when a key is pressed.

Parameters:

keyCode - the key code of the key that was pressed

keyModifier - the key modifier mask of the modifier key that was pressed

keyReleased

void keyReleased(int keyCode,
                 int keyModifier)

Called when a key is released.

Parameters:

keyCode - the key code of the key that was released

keyModifier - the key modifier mask of the modifier key that was released

keyRepeated

void keyRepeated(int keyCode,
                 int keyModifier)

Called when a key is repeated (held down).

Parameters:

keyCode - the key code of the key that was held down

keyModifier - the key modifier mask of the modifier key that was held down