Adobe FLEX 2 - CREATING AND EXTENDING COMPONENTS Manual page 167

A component does not appear on the screen until its
called. Flex schedules a call to the
invalidateDisplayList()
during the next
render
you use the
addChild()
the
invalidateDisplayList()
The main uses of the
Sets the size and position of the elements of the component for display.
■
Many components are made up of one or more child components, or have properties that
control the display of information in the component. For example, the Button control lets
you specify an optional icon, and use the
button text appears relative to the icon.
The
Button.updateDisplayList()
labelPlacement
For containers that have child controls, the
those child components are positioned. For example, the
on the HBox container positions its children from left to right in a single row; the
updateDisplayList()
bottom in a single column.
To size components in the
setActualSize()
position a component, use the
Draws any visual elements necessary for the component.
■
Components support many types of visual elements such as skins, styles, and borders.
Within the
updateDisplayList()
Flash drawing APIs, and perform additional control over the visual display of your
component.
The
updateDisplayList()
protected function updateDisplayList(unscaledWidth:Number,
unscaledHeight:Number):void
updateDisplayList()
method occurs. The
event after a call to the
method to add a component to a container, Flex automatically calls
method.
updateDisplayList()
method uses the settings of the
properties to control the display of the button.
method for a VBox container positions its children from top to
updateDisplayList()
method, not the sizing properties, such as
move()
method, you can add these visual elements, use the
method has the following signature:
updateDisplayList()
method when a call to the
updateDisplayList()
invalidateDisplayList()
method are the following:
property to specify where the
labelPlacement
updateDisplayList()
updateDisplayList()
method, you use the
method, not the and
x
Implementing the component
method gets
method executes
method. When
and
icon
method controls how
method
and . To
width height
properties.
y
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