LzKeys

Keyboard input service.

This service handles keyboard input events.

Here is a simple example:

Example 1. LzKeys

<canvas height="140" debug="true">
  <handler name="onkeydown" reference="LzKeys" args="k">
    Debug.write("key " + k + " down");
  </handler>
  <handler name="onkeyup" reference="LzKeys" args="k">
    Debug.write("key " + k + " up");
  </handler>
  <method name="pressA">
    Debug.write("A pressed");
  </method>
  <handler name="oninit">
    del = new LzDelegate(this, "pressA");
    LzKeys.callOnKeyCombo(del, ["A"]);
  </handler> 
</canvas>

Attributes
Name	Usage	Type (Tag)	Type (JS)	Default	Category
downKeysArray	JS only		Array of Number		readonly
	An array of currently pressed key codes.

downKeysHash	JS only		Object		readonly
	A hash where each of the keys that is currently down on the keyboard is set to true.

keyCodes	JS only		Object		readonly
	A hash that maps key names to key codes.

mousewheeldelta	JS only		Number		readonly
	the amount the mouse wheel last moved. Use onmousewheeldelta to learn when this value changes.

Methods

callOnKeyCombo()
LzKeys.callOnKeyCombo(d, kCArr)
Instructs the service to call the given delegate whenever the given key combination is pressed. The names for recognized special keys are (case-insensitive): numbpad0 numbpad1 numbpad2 numbpad3 numbpad4 numbpad5 numbpad6 numbpad7 numbpad8 numbpad9 multiply enter subtract decimal divide f1 f2 f3 f4 f5 f6 f7 f8 f9 f10 f11 f12 backspace tab clear enter shift control alt capslock esc spacebar pageup pagedown end home leftarrow uparrow rightarrow downarrow insert help numlock add delete 0 1 2 3 4 5 6 7 8 9 [ @ # $ % ^ & * * ( ) ; : = + - _ / ? ~ [ { \ \| ] } " '
Parameters
Name	Type	Desc
d	LzDelegate	The delegate to be called when the keycombo is down.
kCArr	[String]	Array of strings indicating which keys constitute the keycombo. This array may be in any order.

getDownKeys()
LzKeys.getDownKeys()

Returns
Type	Desc
[Number]	array of keys codes that are currently down

isKeyDown()
LzKeys.isKeyDown(k)

Parameters
Name	Type	Desc
k	String	The name of the key to check for downness or an array of key names (e.g. ['shift', 'tab']
Returns
Type	Desc
Boolean	indicating whether the given key is down.

removeKeyComboCall()
LzKeys.removeKeyComboCall(d, kCArr)
Removes the request to call the delegate on the keycombo.
Parameters
Name	Type	Desc
d	LzDelegate	The delegate that was to be called when the keycombo was down.
kCArr	[String]	An array of strings indicating which keys constituted the keycombo.

Events
Name	Description
onkeydown	None
onkeyup	None

Copyright © 2002-2005 Laszlo Systems, Inc. All Rights Reserved. Unauthorized use, duplication or distribution is strictly prohibited. This is the proprietary information of Laszlo Systems, Inc. Use is subject to license terms.