下面列出了java.awt.Container#isFocusCycleRoot ( ) 实例代码，或者点击链接到github查看源代码，也可以在右侧发表评论。
public Component getComponentBefore(Container aContainer,
Component aComponent)
{
Container root = (aContainer.isFocusCycleRoot())
? aContainer
: aContainer.getFocusCycleRootAncestor();
// Support for mixed 1.4/pre-1.4 focus APIs. If a particular root's
// traversal policy is non-legacy, then honor it.
if (root != null) {
FocusTraversalPolicy policy = root.getFocusTraversalPolicy();
if (policy != gluePolicy) {
return policy.getComponentBefore(root, aComponent);
}
comparator.setComponentOrientation(root.getComponentOrientation());
return layoutPolicy.getComponentBefore(root, aComponent);
}
return null;
}
public Component getComponentBefore(Container aContainer,
Component aComponent)
{
Container root = (aContainer.isFocusCycleRoot())
? aContainer
: aContainer.getFocusCycleRootAncestor();
// Support for mixed 1.4/pre-1.4 focus APIs. If a particular root's
// traversal policy is non-legacy, then honor it.
if (root != null) {
FocusTraversalPolicy policy = root.getFocusTraversalPolicy();
if (policy != gluePolicy) {
return policy.getComponentBefore(root, aComponent);
}
comparator.setComponentOrientation(root.getComponentOrientation());
return layoutPolicy.getComponentBefore(root, aComponent);
}
return null;
}
public Component getLastComponent(Container aContainer) {
Container root = (aContainer.isFocusCycleRoot())
? aContainer
: aContainer.getFocusCycleRootAncestor();
// Support for mixed 1.4/pre-1.4 focus APIs. If a particular root's
// traversal policy is non-legacy, then honor it.
if (root != null) {
FocusTraversalPolicy policy = root.getFocusTraversalPolicy();
if (policy != gluePolicy) {
return policy.getLastComponent(root);
}
comparator.setComponentOrientation(root.getComponentOrientation());
return layoutPolicy.getLastComponent(root);
}
return null;
}
public Component getComponentBefore(Container aContainer,
Component aComponent)
{
Container root = (aContainer.isFocusCycleRoot())
? aContainer
: aContainer.getFocusCycleRootAncestor();
// Support for mixed 1.4/pre-1.4 focus APIs. If a particular root's
// traversal policy is non-legacy, then honor it.
if (root != null) {
FocusTraversalPolicy policy = root.getFocusTraversalPolicy();
if (policy != gluePolicy) {
return policy.getComponentBefore(root, aComponent);
}
comparator.setComponentOrientation(root.getComponentOrientation());
return layoutPolicy.getComponentBefore(root, aComponent);
}
return null;
}
public Component getComponentAfter(Container aContainer,
Component aComponent)
{
Container root = (aContainer.isFocusCycleRoot())
? aContainer
: aContainer.getFocusCycleRootAncestor();
// Support for mixed 1.4/pre-1.4 focus APIs. If a particular root's
// traversal policy is non-legacy, then honor it.
if (root != null) {
FocusTraversalPolicy policy = root.getFocusTraversalPolicy();
if (policy != gluePolicy) {
return policy.getComponentAfter(root, aComponent);
}
comparator.setComponentOrientation(root.getComponentOrientation());
return layoutPolicy.getComponentAfter(root, aComponent);
}
return null;
}
public Component getLastComponent(Container aContainer) {
Container root = (aContainer.isFocusCycleRoot())
? aContainer
: aContainer.getFocusCycleRootAncestor();
// Support for mixed 1.4/pre-1.4 focus APIs. If a particular root's
// traversal policy is non-legacy, then honor it.
if (root != null) {
FocusTraversalPolicy policy = root.getFocusTraversalPolicy();
if (policy != gluePolicy) {
return policy.getLastComponent(root);
}
comparator.setComponentOrientation(root.getComponentOrientation());
return layoutPolicy.getLastComponent(root);
}
return null;
}
public Component getLastComponent(Container aContainer) {
Container root = (aContainer.isFocusCycleRoot())
? aContainer
: aContainer.getFocusCycleRootAncestor();
// Support for mixed 1.4/pre-1.4 focus APIs. If a particular root's
// traversal policy is non-legacy, then honor it.
if (root != null) {
FocusTraversalPolicy policy = root.getFocusTraversalPolicy();
if (policy != gluePolicy) {
return policy.getLastComponent(root);
}
comparator.setComponentOrientation(root.getComponentOrientation());
return layoutPolicy.getLastComponent(root);
}
return null;
}
public Component getComponentBefore(Container aContainer,
Component aComponent)
{
Container root = (aContainer.isFocusCycleRoot())
? aContainer
: aContainer.getFocusCycleRootAncestor();
// Support for mixed 1.4/pre-1.4 focus APIs. If a particular root's
// traversal policy is non-legacy, then honor it.
if (root != null) {
FocusTraversalPolicy policy = root.getFocusTraversalPolicy();
if (policy != gluePolicy) {
return policy.getComponentBefore(root, aComponent);
}
comparator.setComponentOrientation(root.getComponentOrientation());
return layoutPolicy.getComponentBefore(root, aComponent);
}
return null;
}
public Component getComponentBefore(Container aContainer,
Component aComponent)
{
Container root = (aContainer.isFocusCycleRoot())
? aContainer
: aContainer.getFocusCycleRootAncestor();
// Support for mixed 1.4/pre-1.4 focus APIs. If a particular root's
// traversal policy is non-legacy, then honor it.
if (root != null) {
FocusTraversalPolicy policy = root.getFocusTraversalPolicy();
if (policy != gluePolicy) {
return policy.getComponentBefore(root, aComponent);
}
comparator.setComponentOrientation(root.getComponentOrientation());
return layoutPolicy.getComponentBefore(root, aComponent);
}
return null;
}
public Component getLastComponent(Container aContainer) {
Container root = (aContainer.isFocusCycleRoot())
? aContainer
: aContainer.getFocusCycleRootAncestor();
// Support for mixed 1.4/pre-1.4 focus APIs. If a particular root's
// traversal policy is non-legacy, then honor it.
if (root != null) {
FocusTraversalPolicy policy = root.getFocusTraversalPolicy();
if (policy != gluePolicy) {
return policy.getLastComponent(root);
}
comparator.setComponentOrientation(root.getComponentOrientation());
return layoutPolicy.getLastComponent(root);
}
return null;
}
public Component getFirstComponent(Container aContainer) {
Container root = (aContainer.isFocusCycleRoot())
? aContainer
: aContainer.getFocusCycleRootAncestor();
// Support for mixed 1.4/pre-1.4 focus APIs. If a particular root's
// traversal policy is non-legacy, then honor it.
if (root != null) {
FocusTraversalPolicy policy = root.getFocusTraversalPolicy();
if (policy != gluePolicy) {
return policy.getFirstComponent(root);
}
comparator.setComponentOrientation(root.getComponentOrientation());
return layoutPolicy.getFirstComponent(root);
}
return null;
}
public Component getComponentBefore(Container aContainer,
Component aComponent)
{
Container root = (aContainer.isFocusCycleRoot())
? aContainer
: aContainer.getFocusCycleRootAncestor();
// Support for mixed 1.4/pre-1.4 focus APIs. If a particular root's
// traversal policy is non-legacy, then honor it.
if (root != null) {
FocusTraversalPolicy policy = root.getFocusTraversalPolicy();
if (policy != gluePolicy) {
return policy.getComponentBefore(root, aComponent);
}
comparator.setComponentOrientation(root.getComponentOrientation());
return layoutPolicy.getComponentBefore(root, aComponent);
}
return null;
}
/**
* Returns the component before.
* @return the component before
* @param aContainer a container
* @param aComponent a component
*/
public Component getComponentBefore(Container aContainer,
Component aComponent)
{
Container root = (aContainer.isFocusCycleRoot())
? aContainer
: aContainer.getFocusCycleRootAncestor();
// Support for mixed 1.4/pre-1.4 focus APIs. If a particular root's
// traversal policy is non-legacy, then honor it.
if (root != null) {
FocusTraversalPolicy policy = root.getFocusTraversalPolicy();
if (policy != gluePolicy) {
return policy.getComponentBefore(root, aComponent);
}
comparator.setComponentOrientation(root.getComponentOrientation());
return layoutPolicy.getComponentBefore(root, aComponent);
}
return null;
}
public Component getComponentAfter(Container aContainer,
Component aComponent)
{
Container root = (aContainer.isFocusCycleRoot())
? aContainer
: aContainer.getFocusCycleRootAncestor();
// Support for mixed 1.4/pre-1.4 focus APIs. If a particular root's
// traversal policy is non-legacy, then honor it.
if (root != null) {
FocusTraversalPolicy policy = root.getFocusTraversalPolicy();
if (policy != gluePolicy) {
return policy.getComponentAfter(root, aComponent);
}
comparator.setComponentOrientation(root.getComponentOrientation());
return layoutPolicy.getComponentAfter(root, aComponent);
}
return null;
}
public Component getComponentBefore(Container aContainer,
Component aComponent)
{
Container root = (aContainer.isFocusCycleRoot())
? aContainer
: aContainer.getFocusCycleRootAncestor();
// Support for mixed 1.4/pre-1.4 focus APIs. If a particular root's
// traversal policy is non-legacy, then honor it.
if (root != null) {
FocusTraversalPolicy policy = root.getFocusTraversalPolicy();
if (policy != gluePolicy) {
return policy.getComponentBefore(root, aComponent);
}
comparator.setComponentOrientation(root.getComponentOrientation());
return layoutPolicy.getComponentBefore(root, aComponent);
}
return null;
}
private Component getComponentDownCycle(Component comp, int traversalDirection) {
Component retComp = null;
if (comp instanceof Container) {
Container cont = (Container)comp;
if (cont.isFocusCycleRoot()) {
if (getImplicitDownCycleTraversal()) {
retComp = cont.getFocusTraversalPolicy().getDefaultComponent(cont);
if (retComp != null && log.isLoggable(PlatformLogger.Level.FINE)) {
log.fine("### Transfered focus down-cycle to " + retComp +
" in the focus cycle root " + cont);
}
} else {
return null;
}
} else if (cont.isFocusTraversalPolicyProvider()) {
retComp = (traversalDirection == FORWARD_TRAVERSAL ?
cont.getFocusTraversalPolicy().getDefaultComponent(cont) :
cont.getFocusTraversalPolicy().getLastComponent(cont));
if (retComp != null && log.isLoggable(PlatformLogger.Level.FINE)) {
log.fine("### Transfered focus to " + retComp + " in the FTP provider " + cont);
}
}
}
return retComp;
}
private Component getComponentDownCycle(Component comp, int traversalDirection) {
Component retComp = null;
if (comp instanceof Container) {
Container cont = (Container)comp;
if (cont.isFocusCycleRoot()) {
if (getImplicitDownCycleTraversal()) {
retComp = cont.getFocusTraversalPolicy().getDefaultComponent(cont);
if (retComp != null && log.isLoggable(PlatformLogger.Level.FINE)) {
log.fine("### Transfered focus down-cycle to " + retComp +
" in the focus cycle root " + cont);
}
} else {
return null;
}
} else if (cont.isFocusTraversalPolicyProvider()) {
retComp = (traversalDirection == FORWARD_TRAVERSAL ?
cont.getFocusTraversalPolicy().getDefaultComponent(cont) :
cont.getFocusTraversalPolicy().getLastComponent(cont));
if (retComp != null && log.isLoggable(PlatformLogger.Level.FINE)) {
log.fine("### Transfered focus to " + retComp + " in the FTP provider " + cont);
}
}
}
return retComp;
}
private Component getComponentDownCycle(Component comp, int traversalDirection) {
Component retComp = null;
if (comp instanceof Container) {
Container cont = (Container)comp;
if (cont.isFocusCycleRoot()) {
if (getImplicitDownCycleTraversal()) {
retComp = cont.getFocusTraversalPolicy().getDefaultComponent(cont);
if (retComp != null && log.isLoggable(PlatformLogger.Level.FINE)) {
log.fine("### Transfered focus down-cycle to " + retComp +
" in the focus cycle root " + cont);
}
} else {
return null;
}
} else if (cont.isFocusTraversalPolicyProvider()) {
retComp = (traversalDirection == FORWARD_TRAVERSAL ?
cont.getFocusTraversalPolicy().getDefaultComponent(cont) :
cont.getFocusTraversalPolicy().getLastComponent(cont));
if (retComp != null && log.isLoggable(PlatformLogger.Level.FINE)) {
log.fine("### Transfered focus to " + retComp + " in the FTP provider " + cont);
}
}
}
return retComp;
}
/**
* Returns the Component that should receive the focus before aComponent.
* aContainer must be a focus cycle root of aComponent or a focus traversal policy provider.
* <p>
* By default, SortingFocusTraversalPolicy implicitly transfers focus down-
* cycle. That is, during normal focus traversal, the Component
* traversed after a focus cycle root will be the focus-cycle-root's
* default Component to focus. This behavior can be disabled using the
* <code>setImplicitDownCycleTraversal</code> method.
* <p>
* If aContainer is <a href="../../java/awt/doc-files/FocusSpec.html#FocusTraversalPolicyProviders">focus
* traversal policy provider</a>, the focus is always transferred down-cycle.
*
* @param aContainer a focus cycle root of aComponent or a focus traversal policy provider
* @param aComponent a (possibly indirect) child of aContainer, or
* aContainer itself
* @return the Component that should receive the focus before aComponent,
* or null if no suitable Component can be found
* @throws IllegalArgumentException if aContainer is not a focus cycle
* root of aComponent or a focus traversal policy provider, or if either aContainer or
* aComponent is null
*/
public Component getComponentBefore(Container aContainer, Component aComponent) {
if (aContainer == null || aComponent == null) {
throw new IllegalArgumentException("aContainer and aComponent cannot be null");
}
if (!aContainer.isFocusTraversalPolicyProvider() && !aContainer.isFocusCycleRoot()) {
throw new IllegalArgumentException("aContainer should be focus cycle root or focus traversal policy provider");
} else if (aContainer.isFocusCycleRoot() && !aComponent.isFocusCycleRoot(aContainer)) {
throw new IllegalArgumentException("aContainer is not a focus cycle root of aComponent");
}
// See if the component is inside of policy provider.
Container provider = getTopmostProvider(aContainer, aComponent);
if (provider != null) {
if (log.isLoggable(PlatformLogger.Level.FINE)) {
log.fine("### Asking FTP " + provider + " for component after " + aComponent);
}
// FTP knows how to find component after the given. We don't.
FocusTraversalPolicy policy = provider.getFocusTraversalPolicy();
Component beforeComp = policy.getComponentBefore(provider, aComponent);
// Null result means that we overstepped the limit of the FTP's cycle.
// In that case we must quit the cycle, otherwise return the component found.
if (beforeComp != null) {
if (log.isLoggable(PlatformLogger.Level.FINE)) {
log.fine("### FTP returned " + beforeComp);
}
return beforeComp;
}
aComponent = provider;
// If the provider is traversable it's returned.
if (accept(aComponent)) {
return aComponent;
}
}
List<Component> cycle = getFocusTraversalCycle(aContainer);
if (log.isLoggable(PlatformLogger.Level.FINE)) {
log.fine("### Cycle is " + cycle + ", component is " + aComponent);
}
int index = getComponentIndex(cycle, aComponent);
if (index < 0) {
if (log.isLoggable(PlatformLogger.Level.FINE)) {
log.fine("### Didn't find component " + aComponent + " in a cycle " + aContainer);
}
return getLastComponent(aContainer);
}
Component comp;
Component tryComp;
for (index--; index>=0; index--) {
comp = cycle.get(index);
if (comp != aContainer && (tryComp = getComponentDownCycle(comp, BACKWARD_TRAVERSAL)) != null) {
return tryComp;
} else if (accept(comp)) {
return comp;
}
}
if (aContainer.isFocusCycleRoot()) {
this.cachedRoot = aContainer;
this.cachedCycle = cycle;
comp = getLastComponent(aContainer);
this.cachedRoot = null;
this.cachedCycle = null;
return comp;
}
return null;
}
/**
* Returns the Component that should receive the focus before aComponent.
* aContainer must be a focus cycle root of aComponent or a focus traversal policy provider.
* <p>
* By default, SortingFocusTraversalPolicy implicitly transfers focus down-
* cycle. That is, during normal focus traversal, the Component
* traversed after a focus cycle root will be the focus-cycle-root's
* default Component to focus. This behavior can be disabled using the
* <code>setImplicitDownCycleTraversal</code> method.
* <p>
* If aContainer is <a href="../../java/awt/doc-files/FocusSpec.html#FocusTraversalPolicyProviders">focus
* traversal policy provider</a>, the focus is always transferred down-cycle.
*
* @param aContainer a focus cycle root of aComponent or a focus traversal policy provider
* @param aComponent a (possibly indirect) child of aContainer, or
* aContainer itself
* @return the Component that should receive the focus before aComponent,
* or null if no suitable Component can be found
* @throws IllegalArgumentException if aContainer is not a focus cycle
* root of aComponent or a focus traversal policy provider, or if either aContainer or
* aComponent is null
*/
public Component getComponentBefore(Container aContainer, Component aComponent) {
if (aContainer == null || aComponent == null) {
throw new IllegalArgumentException("aContainer and aComponent cannot be null");
}
if (!aContainer.isFocusTraversalPolicyProvider() && !aContainer.isFocusCycleRoot()) {
throw new IllegalArgumentException("aContainer should be focus cycle root or focus traversal policy provider");
} else if (aContainer.isFocusCycleRoot() && !aComponent.isFocusCycleRoot(aContainer)) {
throw new IllegalArgumentException("aContainer is not a focus cycle root of aComponent");
}
// See if the component is inside of policy provider.
Container provider = getTopmostProvider(aContainer, aComponent);
if (provider != null) {
if (log.isLoggable(PlatformLogger.Level.FINE)) {
log.fine("### Asking FTP " + provider + " for component after " + aComponent);
}
// FTP knows how to find component after the given. We don't.
FocusTraversalPolicy policy = provider.getFocusTraversalPolicy();
Component beforeComp = policy.getComponentBefore(provider, aComponent);
// Null result means that we overstepped the limit of the FTP's cycle.
// In that case we must quit the cycle, otherwise return the component found.
if (beforeComp != null) {
if (log.isLoggable(PlatformLogger.Level.FINE)) {
log.fine("### FTP returned " + beforeComp);
}
return beforeComp;
}
aComponent = provider;
// If the provider is traversable it's returned.
if (accept(aComponent)) {
return aComponent;
}
}
List<Component> cycle = getFocusTraversalCycle(aContainer);
if (log.isLoggable(PlatformLogger.Level.FINE)) {
log.fine("### Cycle is " + cycle + ", component is " + aComponent);
}
int index = getComponentIndex(cycle, aComponent);
if (index < 0) {
if (log.isLoggable(PlatformLogger.Level.FINE)) {
log.fine("### Didn't find component " + aComponent + " in a cycle " + aContainer);
}
return getLastComponent(aContainer);
}
Component comp;
Component tryComp;
for (index--; index>=0; index--) {
comp = cycle.get(index);
if (comp != aContainer && (tryComp = getComponentDownCycle(comp, BACKWARD_TRAVERSAL)) != null) {
return tryComp;
} else if (accept(comp)) {
return comp;
}
}
if (aContainer.isFocusCycleRoot()) {
this.cachedRoot = aContainer;
this.cachedCycle = cycle;
comp = getLastComponent(aContainer);
this.cachedRoot = null;
this.cachedCycle = null;
return comp;
}
return null;
}