<attribute>
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<attribute>
Sets an attribute of the object that contains it.

The <attribute> tag has two uses:

  1. In a class definiiton, the <attribute> tag defines an attribute that can be set in instances of the class. 

    <canvas height="30"> <class name="mybutton" extends="button">  <attribute name="myattr" type="string" value="after"/> </class>
							<mybutton text="before" myattr="after" onclick="setAttribute('text', this.myattr)"/>
							</canvas>

  2. In an instance, the <attribute> tag attaches an attribute to the instance. The attribute can be accessed from script. 

    <canvas height="30"> <class name="mybutton" extends="button"> <attribute name="myattr" type="string" value="after"/> </class> <mybutton text="before" onclick="setAttribute('text', this.myattr)">
								<attribute name="myattr" value="perhaps later"/> </mybutton> </canvas>

See the Developer's Guide for a complete discussion.

Also see the documentation for <class> . The Classes tutorial describes how to use attributes to define a class.

Attributes

Name (CSS property) Type (tag) Type (js) Default Category
allocation "instance" | "class" String "instance" initialize-only
  One of:
class
The attribute will be an attribute of the class; to refer to it, you say lz.classname.attributename .
instance
Each instance will have an attribute with the specified properties ( name , type , value , etc.).

You can set allocation to class to get static attributes. Static properties are attached to the class itself, for example lz.classname . 

<attribute name="allowed" value="false"
									type="boolean" allocation="class" />
name   String   initialize-only
  The name of the attribute.
required   Boolean "false" initialize-only
  True if this is a required attribute.
style   String   initialize-only
  The CSS property name that can be used to set the value of this attribute under the control of a <stylesheet> (See Chapter 19. Cascading Style Sheets ). style can be any valid CSS property name, and need not be the same as the attribute name; for example you could use the standard CSS property name background-color as the style of the bgcolor attribute. When an attribute has a style property, the value property acts as the default value for the attribute: in the absence of any applicable CSS rule specifying the corresponding property, the attribute will be given the default value. In the case of dynamic CSS, the attribute will revert to the default value if CSS was applied and is removed. (See Dynamic CSS .)
type "boolean" | "color" | "expression" | "number" | "size" | "string" | "text" | "html" String "expression" initialize-only
  The type of the attribute. This determines how the value is parsed. Attributes of type string are automatically quoted if when="immediate", for any other value of when, a literal string would have to be quoted to be used as a value.
value   Object   read/write
  The initial value of the attribute. The type of this value is specified by the value of the type attribute; if that attribute is not present, it's the type of this attribute in this element's tag. The attribute is given this value when the element is created.

Copyright © 2002-2010 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.

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