jdk.awt.Container — clojure-interop/java.awt 1.0.5

A generic Abstract Window Toolkit(AWT) container object is a component that can contain other AWT components.

Components added to a container are tracked in a list. The order of the list will define the components' front-to-back stacking order within the container. If no index is specified when adding a component to a container, it will be added to the end of the list (and hence to the bottom of the stacking order).

Note: For details on the focus subsystem, see

How to Use the Focus Subsystem, a section in The Java Tutorial, and the Focus Specification for more information.

->container clj

(->container)

Constructor.

Constructs a new Container. Containers can be extended directly, but are lightweight in this case and must be contained by a parent somewhere higher up in the component tree that is native. (such as Frame for example).

add clj

(add this comp)

(add this name comp)

(add this comp constraints index)

Adds the specified component to this container with the specified constraints at the specified index. Also notifies the layout manager to add the component to the this container's layout using the specified constraints object. This is a convenience method for addImpl(java.awt.Component, java.lang.Object, int).

This method changes layout-related information, and therefore, invalidates the component hierarchy. If the container has already been displayed, the hierarchy must be validated thereafter in order to display the added component.

comp - the component to be added - java.awt.Component constraints - an object expressing layout constraints for this - java.lang.Object index - the position in the container's list at which to insert the component; -1 means insert at the end component - int

throws: java.lang.NullPointerException - if comp is null

add-container-listener clj

(add-container-listener this l)

Adds the specified container listener to receive container events from this container. If l is null, no exception is thrown and no action is performed. Refer to AWT Threading Issues for details on AWT's threading model.

l - the container listener - java.awt.event.ContainerListener

add-notify clj

(add-notify this)

Makes this Container displayable by connecting it to a native screen resource. Making a container displayable will cause all of its children to be made displayable. This method is called internally by the toolkit and should not be called directly by programs.

add-property-change-listener clj

(add-property-change-listener this listener)

(add-property-change-listener this property-name listener)

Adds a PropertyChangeListener to the listener list for a specific property. The specified property may be user-defined, or one of the following defaults:

this Container's font ("font")
this Container's background color ("background")
this Container's foreground color ("foreground")
this Container's focusability ("focusable")
this Container's focus traversal keys enabled state
    ("focusTraversalKeysEnabled")
this Container's Set of FORWARD_TRAVERSAL_KEYS
    ("forwardFocusTraversalKeys")
this Container's Set of BACKWARD_TRAVERSAL_KEYS
    ("backwardFocusTraversalKeys")
this Container's Set of UP_CYCLE_TRAVERSAL_KEYS
    ("upCycleFocusTraversalKeys")
this Container's Set of DOWN_CYCLE_TRAVERSAL_KEYS
    ("downCycleFocusTraversalKeys")
this Container's focus traversal policy ("focusTraversalPolicy")

this Container's focus-cycle-root state ("focusCycleRoot")
this Container's focus-traversal-policy-provider state("focusTraversalPolicyProvider")
this Container's focus-traversal-policy-provider state("focusTraversalPolicyProvider")

Note that if this Container is inheriting a bound property, then no event will be fired in response to a change in the inherited property.

If listener is null, no exception is thrown and no action is performed.

property-name - one of the property names listed above - java.lang.String listener - the PropertyChangeListener to be added - java.beans.PropertyChangeListener

ancestor-of? clj

(ancestor-of? this c)

Checks if the component is contained in the component hierarchy of this container.

c - the component - java.awt.Component

returns: true if it is an ancestor; false otherwise. - boolean

apply-component-orientation clj

(apply-component-orientation this o)

Sets the ComponentOrientation property of this container and all components contained within it.

This method changes layout-related information, and therefore, invalidates the component hierarchy.

o - the new component orientation of this container and the components contained within it. - java.awt.ComponentOrientation

throws: java.lang.NullPointerException - if orientation is null.

are-focus-traversal-keys-set clj

(are-focus-traversal-keys-set this id)

Returns whether the Set of focus traversal keys for the given focus traversal operation has been explicitly defined for this Container. If this method returns false, this Container is inheriting the Set from an ancestor, or from the current KeyboardFocusManager.

id - one of KeyboardFocusManager.FORWARD_TRAVERSAL_KEYS, KeyboardFocusManager.BACKWARD_TRAVERSAL_KEYS, KeyboardFocusManager.UP_CYCLE_TRAVERSAL_KEYS, or KeyboardFocusManager.DOWN_CYCLE_TRAVERSAL_KEYS - int

returns: true if the the Set of focus traversal keys for the given focus traversal operation has been explicitly defined for this Component; false otherwise. - boolean

throws: java.lang.IllegalArgumentException - if id is not one of KeyboardFocusManager.FORWARD_TRAVERSAL_KEYS, KeyboardFocusManager.BACKWARD_TRAVERSAL_KEYS, KeyboardFocusManager.UP_CYCLE_TRAVERSAL_KEYS, or KeyboardFocusManager.DOWN_CYCLE_TRAVERSAL_KEYS

count-components clj

(count-components this)

Deprecated. As of JDK version 1.1, replaced by getComponentCount().

returns: int

deliver-event clj

(deliver-event this e)

Deprecated. As of JDK version 1.1, replaced by dispatchEvent(AWTEvent e)

e - java.awt.Event

do-layout clj

(do-layout this)

Causes this container to lay out its components. Most programs should not call this method directly, but should invoke the validate method instead.

find-component-at clj

(find-component-at this p)

(find-component-at this x y)

Locates the visible child component that contains the specified position. The top-most child component is returned in the case where there is overlap in the components. If the containing child component is a Container, this method will continue searching for the deepest nested child component. Components which are not visible are ignored during the search.

The findComponentAt method is different from getComponentAt in that getComponentAt only searches the Container's immediate children; if the containing component is a Container, findComponentAt will search that child to find a nested component.

x - the x coordinate - int y - the y coordinate - int

returns: null if the component does not contain the position. If there is no child component at the requested point and the point is within the bounds of the container the container itself is returned. - java.awt.Component

focus-cycle-root? clj

(focus-cycle-root? this)

(focus-cycle-root? this container)

Returns whether the specified Container is the focus cycle root of this Container's focus traversal cycle. Each focus traversal cycle has only a single focus cycle root and each Container which is not a focus cycle root belongs to only a single focus traversal cycle. Containers which are focus cycle roots belong to two cycles: one rooted at the Container itself, and one rooted at the Container's nearest focus-cycle-root ancestor. This method will return true for both such Containers in this case.

container - the Container to be tested - java.awt.Container

returns: true if the specified Container is a focus-cycle- root of this Container; false otherwise - boolean

focus-traversal-policy-provider? clj

(focus-traversal-policy-provider? this)

Returns whether this container provides focus traversal policy. If this property is set to true then when keyboard focus manager searches container hierarchy for focus traversal policy and encounters this container before any other container with this property as true or focus cycle roots then its focus traversal policy will be used instead of focus cycle root's policy.

returns: true if this container provides focus traversal policy, false otherwise - boolean

focus-traversal-policy-set? clj

(focus-traversal-policy-set? this)

Returns whether the focus traversal policy has been explicitly set for this Container. If this method returns false, this Container will inherit its focus traversal policy from an ancestor.

returns: true if the focus traversal policy has been explicitly set for this Container; false otherwise. - boolean

get-alignment-x clj

(get-alignment-x this)

Returns the alignment along the x axis. This specifies how the component would like to be aligned relative to other components. The value should be a number between 0 and 1 where 0 represents alignment along the origin, 1 is aligned the furthest away from the origin, 0.5 is centered, etc.

returns: float

get-alignment-y clj

(get-alignment-y this)

Returns the alignment along the y axis. This specifies how the component would like to be aligned relative to other components. The value should be a number between 0 and 1 where 0 represents alignment along the origin, 1 is aligned the furthest away from the origin, 0.5 is centered, etc.

returns: float

get-component clj

(get-component this n)

Gets the nth component in this container.

Note: This method should be called under AWT tree lock.

n - the index of the component to get. - int

returns: the nth component in this container. - java.awt.Component

throws: java.lang.ArrayIndexOutOfBoundsException - if the nth value does not exist.

get-component-at clj

(get-component-at this p)

(get-component-at this x y)

Locates the component that contains the x,y position. The top-most child component is returned in the case where there is overlap in the components. This is determined by finding the component closest to the index 0 that claims to contain the given point via Component.contains(), except that Components which have native peers take precedence over those which do not (i.e., lightweight Components).

x - the x coordinate - int y - the y coordinate - int

returns: null if the component does not contain the position. If there is no child component at the requested point and the point is within the bounds of the container the container itself is returned; otherwise the top-most child is returned. - java.awt.Component

get-component-count clj

(get-component-count this)

Gets the number of components in this panel.

Note: This method should be called under AWT tree lock.

returns: the number of components in this panel. - int

get-component-z-order clj

(get-component-z-order this comp)

Returns the z-order index of the component inside the container. The higher a component is in the z-order hierarchy, the lower its index. The component with the lowest z-order index is painted last, above all other child components.

comp - the component being queried - java.awt.Component

returns: the z-order index of the component; otherwise returns -1 if the component is null or doesn't belong to the container - int

get-components clj

(get-components this)

Gets all the components in this container.

Note: This method should be called under AWT tree lock.

returns: an array of all the components in this container. - java.awt.Component[]

get-container-listeners clj

(get-container-listeners this)

Returns an array of all the container listeners registered on this container.

returns: all of this container's ContainerListeners or an empty array if no container listeners are currently registered - java.awt.event.ContainerListener[]

get-focus-traversal-keys clj

(get-focus-traversal-keys this id)

Returns the Set of focus traversal keys for a given traversal operation for this Container. (See setFocusTraversalKeys for a full description of each key.)

If a Set of traversal keys has not been explicitly defined for this Container, then this Container's parent's Set is returned. If no Set has been explicitly defined for any of this Container's ancestors, then the current KeyboardFocusManager's default Set is returned.

id - one of KeyboardFocusManager.FORWARD_TRAVERSAL_KEYS, KeyboardFocusManager.BACKWARD_TRAVERSAL_KEYS, KeyboardFocusManager.UP_CYCLE_TRAVERSAL_KEYS, or KeyboardFocusManager.DOWN_CYCLE_TRAVERSAL_KEYS - int

returns: the Set of AWTKeyStrokes for the specified operation. The Set will be unmodifiable, and may be empty. null will never be returned. - java.util.Set<java.awt.AWTKeyStroke>

throws: java.lang.IllegalArgumentException - if id is not one of KeyboardFocusManager.FORWARD_TRAVERSAL_KEYS, KeyboardFocusManager.BACKWARD_TRAVERSAL_KEYS, KeyboardFocusManager.UP_CYCLE_TRAVERSAL_KEYS, or KeyboardFocusManager.DOWN_CYCLE_TRAVERSAL_KEYS

get-focus-traversal-policy clj

(get-focus-traversal-policy this)

Returns the focus traversal policy that will manage keyboard traversal of this Container's children, or null if this Container is not a focus cycle root. If no traversal policy has been explicitly set for this Container, then this Container's focus-cycle-root ancestor's policy is returned.

returns: this Container's focus traversal policy, or null if this Container is not a focus cycle root. - java.awt.FocusTraversalPolicy

get-insets clj

(get-insets this)

Determines the insets of this container, which indicate the size of the container's border.

A Frame object, for example, has a top inset that corresponds to the height of the frame's title bar.

returns: the insets of this container. - java.awt.Insets

get-layout clj

(get-layout this)

Gets the layout manager for this container.

returns: java.awt.LayoutManager

get-listeners clj

(get-listeners this listener-type)

Returns an array of all the objects currently registered as FooListeners upon this Container. FooListeners are registered using the addFooListener method.

You can specify the listenerType argument with a class literal, such as FooListener.class. For example, you can query a Container c for its container listeners with the following code:

ContainerListener[] cls = (ContainerListener[])(c.getListeners(ContainerListener.class));

If no such listeners exist, this method returns an empty array.

listener-type - the type of listeners requested; this parameter should specify an interface that descends from java.util.EventListener - java.lang.Class

returns: an array of all objects registered as FooListeners on this container, or an empty array if no such listeners have been added - <T extends java.util.EventListener> T[]

throws: java.lang.ClassCastException - if listenerType doesn't specify a class or interface that implements java.util.EventListener

get-maximum-size clj

(get-maximum-size this)

Returns the maximum size of this container. If the maximum size has not been set explicitly by Component.setMaximumSize(Dimension) and the LayoutManager installed on this Container is an instance of LayoutManager2, then LayoutManager2.maximumLayoutSize(Container) is used to calculate the maximum size.

Note: some implementations may cache the value returned from the LayoutManager2. Implementations that cache need not invoke maximumLayoutSize on the LayoutManager2 every time this method is invoked, rather the LayoutManager2 will only be queried after the Container becomes invalid.

returns: an instance of Dimension that represents the maximum size of this container. - java.awt.Dimension

get-minimum-size clj

(get-minimum-size this)

Returns the minimum size of this container. If the minimum size has not been set explicitly by Component.setMinimumSize(Dimension) and this Container has a non-null LayoutManager, then LayoutManager.minimumLayoutSize(Container) is used to calculate the minimum size.

Note: some implementations may cache the value returned from the LayoutManager. Implementations that cache need not invoke minimumLayoutSize on the LayoutManager every time this method is invoked, rather the LayoutManager will only be queried after the Container becomes invalid.

returns: an instance of Dimension that represents the minimum size of this container. - java.awt.Dimension

get-mouse-position clj

(get-mouse-position this allow-children)

Returns the position of the mouse pointer in this Container's coordinate space if the Container is under the mouse pointer, otherwise returns null. This method is similar to Component.getMousePosition() with the exception that it can take the Container's children into account. If allowChildren is false, this method will return a non-null value only if the mouse pointer is above the Container directly, not above the part obscured by children. If allowChildren is true, this method returns a non-null value if the mouse pointer is above Container or any of its descendants.

allow-children - true if children should be taken into account - boolean

returns: mouse coordinates relative to this Component, or null - java.awt.Point

throws: java.awt.HeadlessException - if GraphicsEnvironment.isHeadless() returns true

get-preferred-size clj

(get-preferred-size this)

Returns the preferred size of this container. If the preferred size has not been set explicitly by Component.setPreferredSize(Dimension) and this Container has a non-null LayoutManager, then LayoutManager.preferredLayoutSize(Container) is used to calculate the preferred size.

Note: some implementations may cache the value returned from the LayoutManager. Implementations that cache need not invoke preferredLayoutSize on the LayoutManager every time this method is invoked, rather the LayoutManager will only be queried after the Container becomes invalid.

returns: an instance of Dimension that represents the preferred size of this container. - java.awt.Dimension

insets clj

(insets this)

Deprecated. As of JDK version 1.1, replaced by getInsets().

returns: java.awt.Insets

invalidate clj

(invalidate this)

Invalidates the container.

If the LayoutManager installed on this container is an instance of the LayoutManager2 interface, then the LayoutManager2.invalidateLayout(Container) method is invoked on it supplying this Container as the argument.

Afterwards this method marks this container invalid, and invalidates its ancestors. See the Component.invalidate() method for more details.

layout clj

(layout this)

Deprecated. As of JDK version 1.1, replaced by doLayout().

list clj

(list this out indent)

Prints a listing of this container to the specified output stream. The listing starts at the specified indentation.

The immediate children of the container are printed with an indentation of indent+1. The children of those children are printed at indent+2 and so on.

out - a print stream - java.io.PrintStream indent - the number of spaces to indent - int

throws: java.lang.NullPointerException - if out is null

locate clj

(locate this x y)

Deprecated. As of JDK version 1.1, replaced by getComponentAt(int, int).

x - int y - int

returns: java.awt.Component

minimum-size clj

(minimum-size this)

Deprecated. As of JDK version 1.1, replaced by getMinimumSize().

returns: java.awt.Dimension

paint clj

(paint this g)

Paints the container. This forwards the paint to any lightweight components that are children of this container. If this method is reimplemented, super.paint(g) should be called so that lightweight components are properly rendered. If a child component is entirely clipped by the current clipping setting in g, paint() will not be forwarded to that child.

g - the specified Graphics window - java.awt.Graphics

paint-components clj

(paint-components this g)

Paints each of the components in this container.

g - the graphics context. - java.awt.Graphics

preferred-size clj

(preferred-size this)

Deprecated. As of JDK version 1.1, replaced by getPreferredSize().

returns: java.awt.Dimension

print clj

(print this g)

Prints the container. This forwards the print to any lightweight components that are children of this container. If this method is reimplemented, super.print(g) should be called so that lightweight components are properly rendered. If a child component is entirely clipped by the current clipping setting in g, print() will not be forwarded to that child.

g - the specified Graphics window - java.awt.Graphics

print-components clj

(print-components this g)

Prints each of the components in this container.

g - the graphics context. - java.awt.Graphics

remove clj

(remove this index)

Removes the component, specified by index, from this container. This method also notifies the layout manager to remove the component from this container's layout via the removeLayoutComponent method.

This method changes layout-related information, and therefore, invalidates the component hierarchy. If the container has already been displayed, the hierarchy must be validated thereafter in order to reflect the changes.

index - the index of the component to be removed - int

throws: java.lang.ArrayIndexOutOfBoundsException - if index is not in range [0, getComponentCount()-1]

remove-all clj

(remove-all this)

Removes all the components from this container. This method also notifies the layout manager to remove the components from this container's layout via the removeLayoutComponent method.

This method changes layout-related information, and therefore, invalidates the component hierarchy. If the container has already been displayed, the hierarchy must be validated thereafter in order to reflect the changes.

remove-container-listener clj

(remove-container-listener this l)

Removes the specified container listener so it no longer receives container events from this container. If l is null, no exception is thrown and no action is performed. Refer to AWT Threading Issues for details on AWT's threading model.

l - the container listener - java.awt.event.ContainerListener

remove-notify clj

(remove-notify this)

Makes this Container undisplayable by removing its connection to its native screen resource. Making a container undisplayable will cause all of its children to be made undisplayable. This method is called by the toolkit internally and should not be called directly by programs.

set-component-z-order clj

(set-component-z-order this comp index)

Moves the specified component to the specified z-order index in the container. The z-order determines the order that components are painted; the component with the highest z-order paints first and the component with the lowest z-order paints last. Where components overlap, the component with the lower z-order paints over the component with the higher z-order.

If the component is a child of some other container, it is removed from that container before being added to this container. The important difference between this method and java.awt.Container.add(Component, int) is that this method doesn't call removeNotify on the component while removing it from its previous container unless necessary and when allowed by the underlying native windowing system. This way, if the component has the keyboard focus, it maintains the focus when moved to the new position.

This property is guaranteed to apply only to lightweight non-Container components.

This method changes layout-related information, and therefore, invalidates the component hierarchy.

Note: Not all platforms support changing the z-order of heavyweight components from one container into another without the call to removeNotify. There is no way to detect whether a platform supports this, so developers shouldn't make any assumptions.

comp - the component to be moved - java.awt.Component index - the position in the container's list to insert the component, where getComponentCount() appends to the end - int

throws: java.lang.NullPointerException - if comp is null

set-focus-cycle-root clj

(set-focus-cycle-root this focus-cycle-root)

Sets whether this Container is the root of a focus traversal cycle. Once focus enters a traversal cycle, typically it cannot leave it via focus traversal unless one of the up- or down-cycle keys is pressed. Normal traversal is limited to this Container, and all of this Container's descendants that are not descendants of inferior focus cycle roots. Note that a FocusTraversalPolicy may bend these restrictions, however. For example, ContainerOrderFocusTraversalPolicy supports implicit down-cycle traversal.

The alternative way to specify the traversal order of this Container's children is to make this Container a focus traversal policy provider.

focus-cycle-root - indicates whether this Container is the root of a focus traversal cycle - boolean

set-focus-traversal-keys clj

(set-focus-traversal-keys this id keystrokes)

Sets the focus traversal keys for a given traversal operation for this Container.

The default values for a Container's focus traversal keys are implementation-dependent. Sun recommends that all implementations for a particular native platform use the same default values. The recommendations for Windows and Unix are listed below. These recommendations are used in the Sun AWT implementations.

Identifier
Meaning
Default


KeyboardFocusManager.FORWARD_TRAVERSAL_KEYS
Normal forward keyboard traversal
TAB on KEY_PRESSED, CTRL-TAB on KEY_PRESSED


KeyboardFocusManager.BACKWARD_TRAVERSAL_KEYS
Normal reverse keyboard traversal
SHIFT-TAB on KEY_PRESSED, CTRL-SHIFT-TAB on KEY_PRESSED


KeyboardFocusManager.UP_CYCLE_TRAVERSAL_KEYS
Go up one focus traversal cycle
none


KeyboardFocusManager.DOWN_CYCLE_TRAVERSAL_KEYS
Go down one focus traversal cycle
none

To disable a traversal key, use an empty Set; Collections.EMPTY_SET is recommended.

Using the AWTKeyStroke API, client code can specify on which of two specific KeyEvents, KEY_PRESSED or KEY_RELEASED, the focus traversal operation will occur. Regardless of which KeyEvent is specified, however, all KeyEvents related to the focus traversal key, including the associated KEY_TYPED event, will be consumed, and will not be dispatched to any Container. It is a runtime error to specify a KEY_TYPED event as mapping to a focus traversal operation, or to map the same event to multiple default focus traversal operations.

If a value of null is specified for the Set, this Container inherits the Set from its parent. If all ancestors of this Container have null specified for the Set, then the current KeyboardFocusManager's default Set is used.

This method may throw a ClassCastException if any Object in keystrokes is not an AWTKeyStroke.

id - one of KeyboardFocusManager.FORWARD_TRAVERSAL_KEYS, KeyboardFocusManager.BACKWARD_TRAVERSAL_KEYS, KeyboardFocusManager.UP_CYCLE_TRAVERSAL_KEYS, or KeyboardFocusManager.DOWN_CYCLE_TRAVERSAL_KEYS - int keystrokes - the Set of AWTKeyStroke for the specified operation - java.util.Set

throws: java.lang.IllegalArgumentException - if id is not one of KeyboardFocusManager.FORWARD_TRAVERSAL_KEYS, KeyboardFocusManager.BACKWARD_TRAVERSAL_KEYS, KeyboardFocusManager.UP_CYCLE_TRAVERSAL_KEYS, or KeyboardFocusManager.DOWN_CYCLE_TRAVERSAL_KEYS, or if keystrokes contains null, or if any keystroke represents a KEY_TYPED event, or if any keystroke already maps to another focus traversal operation for this Container

set-focus-traversal-policy clj

(set-focus-traversal-policy this policy)

Sets the focus traversal policy that will manage keyboard traversal of this Container's children, if this Container is a focus cycle root. If the argument is null, this Container inherits its policy from its focus- cycle-root ancestor. If the argument is non-null, this policy will be inherited by all focus-cycle-root children that have no keyboard- traversal policy of their own (as will, recursively, their focus-cycle- root children).

If this Container is not a focus cycle root, the policy will be remembered, but will not be used or inherited by this or any other Containers until this Container is made a focus cycle root.

policy - the new focus traversal policy for this Container - java.awt.FocusTraversalPolicy

set-focus-traversal-policy-provider clj

(set-focus-traversal-policy-provider this provider)

Sets whether this container will be used to provide focus traversal policy. Container with this property as true will be used to acquire focus traversal policy instead of closest focus cycle root ancestor.

provider - indicates whether this container will be used to provide focus traversal policy - boolean

set-font clj

(set-font this f)

Sets the font of this container.

This method changes layout-related information, and therefore, invalidates the component hierarchy.

f - The font to become this container's font. - java.awt.Font

set-layout clj

(set-layout this mgr)

Sets the layout manager for this container.

This method changes layout-related information, and therefore, invalidates the component hierarchy.

mgr - the specified layout manager - java.awt.LayoutManager

transfer-focus-down-cycle clj

(transfer-focus-down-cycle this)

Transfers the focus down one focus traversal cycle. If this Container is a focus cycle root, then the focus owner is set to this Container's default Component to focus, and the current focus cycle root is set to this Container. If this Container is not a focus cycle root, then no focus traversal operation occurs.

update clj

(update this g)

Updates the container. This forwards the update to any lightweight components that are children of this container. If this method is reimplemented, super.update(g) should be called so that lightweight components are properly rendered. If a child component is entirely clipped by the current clipping setting in g, update() will not be forwarded to that child.

g - the specified Graphics window - java.awt.Graphics

validate clj

(validate this)

Validates this container and all of its subcomponents.

Validating a container means laying out its subcomponents. Layout-related changes, such as setting the bounds of a component, or adding a component to the container, invalidate the container automatically. Note that the ancestors of the container may be invalidated also (see Component.invalidate() for details.) Therefore, to restore the validity of the hierarchy, the validate() method should be invoked on the top-most invalid container of the hierarchy.

Validating the container may be a quite time-consuming operation. For performance reasons a developer may postpone the validation of the hierarchy till a set of layout-related operations completes, e.g. after adding all the children to the container.

If this Container is not valid, this method invokes the validateTree method and marks this Container as valid. Otherwise, no action is performed.

validate-root? clj

(validate-root? this)

Indicates if this container is a validate root.

Layout-related changes, such as bounds of the validate root descendants, do not affect the layout of the validate root parent. This peculiarity enables the invalidate() method to stop invalidating the component hierarchy when the method encounters a validate root. However, to preserve backward compatibility this new optimized behavior is enabled only when the java.awt.smartInvalidate system property value is set to true.

If a component hierarchy contains validate roots and the new optimized invalidate() behavior is enabled, the validate() method must be invoked on the validate root of a previously invalidated component to restore the validity of the hierarchy later. Otherwise, calling the validate() method on the top-level container (such as a Frame object) should be used to restore the validity of the component hierarchy.

The Window class and the Applet class are the validate roots in AWT. Swing introduces more validate roots.

returns: whether this container is a validate root - boolean