Class BasicTreeUI.ComponentHandler

java.lang.Object

java.awt.event.ComponentAdapter

javax.swing.plaf.basic.BasicTreeUI.ComponentHandler

All Implemented Interfaces:: ActionListener, ComponentListener, EventListener

Enclosing class:: BasicTreeUI

public class BasicTreeUI.ComponentHandler extends ComponentAdapter implements ActionListener

Updates the preferred size when scrolling (if necessary).

Field Summary

Modifier and Type	Field	Description
`protected JScrollBar`	`scrollBar`	ScrollBar that is being adjusted.
`protected Timer`	`timer`	Timer used when inside a scrollpane and the scrollbar is adjusting.

Constructor Summary

Constructor	Description
`ComponentHandler()`	Constructs a `ComponentHandler`.

Method Summary

Modifier and Type	Method	Description
`void`	`actionPerformed(ActionEvent ae)`	Public as a result of Timer.
`protected JScrollPane`	`getScrollPane()`	Returns the `JScrollPane` housing the `JTree`, or null if one isn't found.
`protected void`	`startTimer()`	Creates, if necessary, and starts a Timer to check if need to resize the bounds.

Methods declared in class ComponentAdapter

componentHidden, componentMoved, componentResized, componentShown

Modifier and Type	Method	Description
`void`	`componentHidden(ComponentEvent e)`	Invoked when the component has been made invisible.
`void`	`componentMoved(ComponentEvent e)`	Invoked when the component's position changes.
`void`	`componentResized(ComponentEvent e)`	Invoked when the component's size changes.
`void`	`componentShown(ComponentEvent e)`	Invoked when the component has been made visible.

Methods declared in class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Modifier and Type	Method	Description
`protected Object`	`clone()`	Creates and returns a copy of this object.
`boolean`	`equals(Object obj)`	Indicates whether some other object is "equal to" this one.
`protected void`	`finalize()`	Deprecated, for removal: This API element is subject to removal in a future version. Finalization is deprecated and subject to removal in a future release.
`final Class<?>`	`getClass()`	Returns the runtime class of this `Object`.
`int`	`hashCode()`	Returns a hash code value for this object.
`final void`	`notify()`	Wakes up a single thread that is waiting on this object's monitor.
`final void`	`notifyAll()`	Wakes up all threads that are waiting on this object's monitor.
`String`	`toString()`	Returns a string representation of the object.
`final void`	`wait()`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted.
`final void`	`wait(long timeoutMillis)`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
`final void`	`wait(long timeoutMillis, int nanos)`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

Field Details

timer

protected Timer timer

Timer used when inside a scrollpane and the scrollbar is adjusting.

scrollBar

protected JScrollBar scrollBar

ScrollBar that is being adjusted.

Constructor Details

ComponentHandler

public ComponentHandler()

Constructs a ComponentHandler.

Method Details

startTimer

protected void startTimer()

Creates, if necessary, and starts a Timer to check if need to resize the bounds.

getScrollPane

protected JScrollPane getScrollPane()

Returns the JScrollPane housing the JTree, or null if one isn't found.

Returns:: the JScrollPane housing the JTree

actionPerformed

public void actionPerformed(ActionEvent ae)

Public as a result of Timer. If the scrollBar is null, or not adjusting, this stops the timer and updates the sizing.

Specified by:: actionPerformed in interface ActionListener
Parameters:: ae - the event to be processed

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