/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
import javax.accessibility.*;
/**
* vertical scrolling for a single child component. The display
* policy for the scrollbars can be set to:
* <OL>
* <LI>as needed: scrollbars created and shown only when needed by scrollpane
* <LI>always: scrollbars created and always shown by the scrollpane
* <LI>never: scrollbars never created or shown by the scrollpane
* </OL>
* <P>
* The state of the horizontal and vertical scrollbars is represented
* by two <code>ScrollPaneAdjustable</code> objects (one for each
* dimension) which implement the <code>Adjustable</code> interface.
* The API provides methods to access those objects such that the
* attributes on the Adjustable object (such as unitIncrement, value,
* etc.) can be manipulated.
* <P>
* Certain adjustable properties (minimum, maximum, blockIncrement,
* and visibleAmount) are set internally by the scrollpane in accordance
* with the geometry of the scrollpane and its child and these should
* not be set by programs using the scrollpane.
* <P>
* If the scrollbar display policy is defined as "never", then the
* scrollpane can still be programmatically scrolled using the
* setScrollPosition() method and the scrollpane will move and clip
* the child's contents appropriately. This policy is useful if the
* program needs to create and manage its own adjustable controls.
* <P>
* The placement of the scrollbars is controlled by platform-specific
* properties set by the user outside of the program.
* <P>
* The initial size of this container is set to 100x100, but can
* be reset using setSize().
* <P>
* Scrolling with the wheel on a wheel-equipped mouse is enabled by default.
* This can be disabled using <code>setWheelScrollingEnabled</code>.
* Wheel scrolling can be customized by setting the block and
* unit increment of the horizontal and vertical Adjustables.
* For information on how mouse wheel events are dispatched, see
* the class description for {@link MouseWheelEvent}.
* <P>
* Insets are used to define any space used by scrollbars and any
* borders created by the scroll pane. getInsets() can be used
* to get the current value for the insets. If the value of
* scrollbarsAlwaysVisible is false, then the value of the insets
* will change dynamically depending on whether the scrollbars are
* currently visible or not.
*
* @author Tom Ball
* @author Amy Fowler
* @author Tim Prinzing
*/
/**
* Initialize JNI field and method IDs
*/
private static native void initIDs();
static {
/* ensure that the necessary native libraries are loaded */
if (!GraphicsEnvironment.isHeadless()) {
initIDs();
}
}
/**
* Specifies that horizontal/vertical scrollbar should be shown
* only when the size of the child exceeds the size of the scrollpane
* in the horizontal/vertical dimension.
*/
/**
* Specifies that horizontal/vertical scrollbars should always be
* shown regardless of the respective sizes of the scrollpane and child.
*/
/**
* Specifies that horizontal/vertical scrollbars should never be shown
* regardless of the respective sizes of the scrollpane and child.
*/
/**
* There are 3 ways in which a scroll bar can be displayed.
* This integer will represent one of these 3 displays -
* (SCROLLBARS_ALWAYS, SCROLLBARS_AS_NEEDED, SCROLLBARS_NEVER)
*
* @serial
* @see #getScrollbarDisplayPolicy
*/
private int scrollbarDisplayPolicy;
/**
* An adjustable vertical scrollbar.
* It is important to note that you must <em>NOT</em> call 3
* <code>Adjustable</code> methods, namely:
* <code>setMinimum()</code>, <code>setMaximum()</code>,
* <code>setVisibleAmount()</code>.
*
* @serial
* @see #getVAdjustable
*/
/**
* An adjustable horizontal scrollbar.
* It is important to note that you must <em>NOT</em> call 3
* <code>Adjustable</code> methods, namely:
* <code>setMinimum()</code>, <code>setMaximum()</code>,
* <code>setVisibleAmount()</code>.
*
* @serial
* @see #getHAdjustable
*/
private static final boolean defaultWheelScroll = true;
/**
* Indicates whether or not scrolling should take place when a
* MouseWheelEvent is received.
*
* @serial
* @since 1.4
*/
/*
* JDK 1.1 serialVersionUID
*/
/**
* Create a new scrollpane container with a scrollbar display
* policy of "as needed".
* @throws HeadlessException if GraphicsEnvironment.isHeadless()
* returns true
* @see java.awt.GraphicsEnvironment#isHeadless
*/
this(SCROLLBARS_AS_NEEDED);
}
/**
* Create a new scrollpane container.
* @param scrollbarDisplayPolicy policy for when scrollbars should be shown
* @throws IllegalArgumentException if the specified scrollbar
* display policy is invalid
* @throws HeadlessException if GraphicsEnvironment.isHeadless()
* returns true
* @see java.awt.GraphicsEnvironment#isHeadless
*/
@ConstructorProperties({"scrollbarDisplayPolicy"})
this.width = 100;
this.height = 100;
switch (scrollbarDisplayPolicy) {
case SCROLLBARS_NEVER:
case SCROLLBARS_AS_NEEDED:
case SCROLLBARS_ALWAYS:
break;
default:
throw new IllegalArgumentException("illegal scrollbar display policy");
}
}
/**
* Construct a name for this component. Called by getName() when the
* name is null.
*/
synchronized (ScrollPane.class) {
return base + nameCounter++;
}
}
// The scrollpane won't work with a windowless child... it assumes
// it is moving a child window around so the windowless child is
// wrapped with a window.
validate();
}
/**
* Adds the specified component to this scroll pane container.
* If the scroll pane has an existing child component, that
* component is removed and the new one is added.
* @param comp the component to be added
* @param constraints not applicable
* @param index position of child component (must be <= 0)
*/
synchronized (getTreeLock()) {
if (getComponentCount() > 0) {
remove(0);
}
if (index > 0) {
throw new IllegalArgumentException("position greater than 0");
}
} else {
}
}
}
/**
* Returns the display policy for the scrollbars.
* @return the display policy for the scrollbars
*/
public int getScrollbarDisplayPolicy() {
return scrollbarDisplayPolicy;
}
/**
* Returns the current size of the scroll pane's view port.
* @return the size of the view port in pixels
*/
}
/**
* Returns the height that would be occupied by a horizontal
* scrollbar, which is independent of whether it is currently
* displayed by the scroll pane or not.
* @return the height of a horizontal scrollbar in pixels
*/
public int getHScrollbarHeight() {
int h = 0;
if (scrollbarDisplayPolicy != SCROLLBARS_NEVER) {
h = peer.getHScrollbarHeight();
}
}
return h;
}
/**
* Returns the width that would be occupied by a vertical
* scrollbar, which is independent of whether it is currently
* displayed by the scroll pane or not.
* @return the width of a vertical scrollbar in pixels
*/
public int getVScrollbarWidth() {
int w = 0;
if (scrollbarDisplayPolicy != SCROLLBARS_NEVER) {
w = peer.getVScrollbarWidth();
}
}
return w;
}
/**
* Returns the <code>ScrollPaneAdjustable</code> object which
* represents the state of the vertical scrollbar.
* The declared return type of this method is
* <code>Adjustable</code> to maintain backward compatibility.
* @see java.awt.ScrollPaneAdjustable
*/
return vAdjustable;
}
/**
* Returns the <code>ScrollPaneAdjustable</code> object which
* represents the state of the horizontal scrollbar.
* The declared return type of this method is
* <code>Adjustable</code> to maintain backward compatibility.
* @see java.awt.ScrollPaneAdjustable
*/
return hAdjustable;
}
/**
* Scrolls to the specified position within the child component.
* A call to this method is only valid if the scroll pane contains
* a child. Specifying a position outside of the legal scrolling bounds
* of the child will scroll to the closest legal position.
* Legal bounds are defined to be the rectangle:
* x = 0, y = 0, width = (child width - view port width),
* height = (child height - view port height).
* This is a convenience method which interfaces with the Adjustable
* objects which represent the state of the scrollbars.
* @param x the x position to scroll to
* @param y the y position to scroll to
* @throws NullPointerException if the scrollpane does not contain
* a child
*/
public void setScrollPosition(int x, int y) {
synchronized (getTreeLock()) {
if (getComponentCount()==0) {
throw new NullPointerException("child is null");
}
hAdjustable.setValue(x);
vAdjustable.setValue(y);
}
}
/**
* Scrolls to the specified position within the child component.
* A call to this method is only valid if the scroll pane contains
* a child and the specified position is within legal scrolling bounds
* of the child. Specifying a position outside of the legal scrolling
* bounds of the child will scroll to the closest legal position.
* Legal bounds are defined to be the rectangle:
* x = 0, y = 0, width = (child width - view port width),
* height = (child height - view port height).
* This is a convenience method which interfaces with the Adjustable
* objects which represent the state of the scrollbars.
* @param p the Point representing the position to scroll to
* @throws NullPointerException if {@code p} is {@code null}
*/
setScrollPosition(p.x, p.y);
}
/**
* Returns the current x,y position within the child which is displayed
* at the 0,0 location of the scrolled panel's view port.
* This is a convenience method which interfaces with the adjustable
* objects which represent the state of the scrollbars.
* @return the coordinate position for the current scroll position
* @throws NullPointerException if the scrollpane does not contain
* a child
*/
synchronized (getTreeLock()) {
if (getComponentCount()==0) {
throw new NullPointerException("child is null");
}
}
}
/**
* Sets the layout manager for this container. This method is
* overridden to prevent the layout mgr from being set.
* @param mgr the specified layout manager
*/
throw new AWTError("ScrollPane controls layout");
}
/**
* Lays out this container by resizing its child to its preferred size.
* If the new preferred size of the child causes the current scroll
* position to be invalid, the scroll position is set to the closest
* valid position.
*
* @see Component#validate
*/
public void doLayout() {
layout();
}
/**
* Determine the size to allocate the child component.
* If the viewport area is bigger than the childs
* preferred size then the child is allocated enough
* to fill the viewport, otherwise the child is given
* it's preferred size.
*/
//
// calculate the view size, accounting for border but not scrollbars
// on whether or not scrollbars were displayed on last resize
//
//
// determine whether or not horz or vert scrollbars will be displayed
//
boolean vbarOn;
boolean hbarOn;
if (scrollbarDisplayPolicy == SCROLLBARS_AS_NEEDED) {
} else if (scrollbarDisplayPolicy == SCROLLBARS_ALWAYS) {
} else { // SCROLLBARS_NEVER
}
//
// adjust predicted view size to account for scrollbars
//
int vbarWidth = getVScrollbarWidth();
int hbarHeight = getHScrollbarHeight();
if (vbarOn) {
}
if(hbarOn) {
viewHeight -= hbarHeight;
}
//
// if child is smaller than view, size it up
//
}
}
return childSize;
}
/**
* @deprecated As of JDK version 1.1,
* replaced by <code>doLayout()</code>.
*/
public void layout() {
if (getComponentCount()==0) {
return;
}
Point p = getScrollPosition();
}
// update adjustables... the viewport size may have changed
// with the scrollbars coming or going so the viewport size
// is updated before the adjustables.
vs = getViewportSize();
}
/**
* Prints the component in this scroll pane.
* @param g the specified Graphics window
* @see Component#print
* @see Component#printAll
*/
if (getComponentCount()==0) {
return;
}
Point p = c.getLocation();
try {
} finally {
}
}
/**
* Creates the scroll pane's peer.
*/
public void addNotify() {
synchronized (getTreeLock()) {
int vAdjustableValue = 0;
int hAdjustableValue = 0;
// Bug 4124460. Save the current adjustable values,
// so they can be restored after addnotify. Set the
// adjustables to 0, to prevent crashes for possible
// negative values.
if (getComponentCount() > 0) {
}
super.addNotify();
// Bug 4124460. Restore the adjustable values.
if (getComponentCount() > 0) {
}
}
}
/**
* Returns a string representing the state of this
* <code>ScrollPane</code>. This
* method is intended to be used only for debugging purposes, and the
* content and format of the returned string may vary between
* implementations. The returned string may be empty but may not be
* <code>null</code>.
*
* @return the parameter string of this scroll pane
*/
switch (scrollbarDisplayPolicy) {
case SCROLLBARS_AS_NEEDED:
sdpStr = "as-needed";
break;
case SCROLLBARS_ALWAYS:
sdpStr = "always";
break;
case SCROLLBARS_NEVER:
sdpStr = "never";
break;
default:
sdpStr = "invalid display policy";
}
",ScrollbarDisplayPolicy="+sdpStr+
",wheelScrollingEnabled="+isWheelScrollingEnabled();
}
}
/**
* Process mouse wheel events that are delivered to this
* <code>ScrollPane</code> by scrolling an appropriate amount.
* <p>Note that if the event parameter is <code>null</code>
* the behavior is unspecified and may result in an
* exception.
*
* @param e the mouse wheel event
* @since 1.4
*/
if (isWheelScrollingEnabled()) {
ScrollPaneWheelScroller.handleWheelScrolling(this, e);
e.consume();
}
super.processMouseWheelEvent(e);
}
/**
* If wheel scrolling is enabled, we return true for MouseWheelEvents
* @since 1.4
*/
return true;
}
else {
return super.eventTypeEnabled(type);
}
}
/**
* Wheel scrolling is enabled by default.
*
* @param handleWheel <code>true</code> if scrolling should be done
* automatically for a MouseWheelEvent,
* <code>false</code> otherwise.
* @see #isWheelScrollingEnabled
* @see java.awt.event.MouseWheelEvent
* @see java.awt.event.MouseWheelListener
* @since 1.4
*/
}
/**
* Indicates whether or not scrolling will take place in response to
* the mouse wheel. Wheel scrolling is enabled by default.
*
* @see #setWheelScrollingEnabled(boolean)
* @since 1.4
*/
public boolean isWheelScrollingEnabled() {
return wheelScrollingEnabled;
}
/**
* Writes default serializable fields to stream.
*/
// 4352819: We only need this degenerate writeObject to make
// it safe for future versions of this class to write optional
// data to the stream.
s.defaultWriteObject();
}
/**
* Reads default serializable fields to stream.
* @exception HeadlessException if
* <code>GraphicsEnvironment.isHeadless()</code> returns
* <code>true</code>
* @see java.awt.GraphicsEnvironment#isHeadless
*/
{
// 4352819: Gotcha! Cannot use s.defaultReadObject here and
// then continue with reading optional data. Use GetField instead.
// Old fields
// Since 1.4
// // Note to future maintainers
// if (f.defaulted("wheelScrollingEnabled")) {
// // We are reading pre-1.4 stream that doesn't have
// // optional data, not even the TC_ENDBLOCKDATA marker.
// // Reading anything after this point is unsafe as we will
// // read unrelated objects further down the stream (4352819).
// }
// else {
// // Reading data from 1.4 or later, it's ok to try to read
// // optional data as OptionalDataException with eof == true
// // will be correctly reported
// }
}
{
}
/**
* Invoked when the value of the adjustable has changed.
*/
}
switch(adj.getOrientation()) {
case Adjustable.VERTICAL:
break;
case Adjustable.HORIZONTAL:
break;
default:
throw new IllegalArgumentException("Illegal adjustable orientation");
}
}
}
/////////////////
// Accessibility support
////////////////
/**
* Gets the AccessibleContext associated with this ScrollPane.
* For scroll panes, the AccessibleContext takes the form of an
* AccessibleAWTScrollPane.
* A new AccessibleAWTScrollPane instance is created if necessary.
*
* @return an AccessibleAWTScrollPane that serves as the
* AccessibleContext of this ScrollPane
* @since 1.3
*/
if (accessibleContext == null) {
accessibleContext = new AccessibleAWTScrollPane();
}
return accessibleContext;
}
/**
* This class implements accessibility support for the
* <code>ScrollPane</code> class. It provides an implementation of the
* Java Accessibility API appropriate to scroll pane user-interface
* elements.
* @since 1.3
*/
{
/*
* JDK 1.3 serialVersionUID
*/
/**
* Get the role of this object.
*
* @return an instance of AccessibleRole describing the role of the
* object
* @see AccessibleRole
*/
return AccessibleRole.SCROLL_PANE;
}
} // class AccessibleAWTScrollPane
}
/*
* In JDK 1.1.1, the pkg private class java.awt.PeerFixer was moved to
* become an inner class of ScrollPane, which broke serialization
* for ScrollPane objects using JDK 1.1.
* Instead of moving it back out here, which would break all JDK 1.1.x
* releases, we keep PeerFixer in both places. Because of the scoping rules,
* the PeerFixer that is used in ScrollPane will be the one that is the
* inner class. This pkg private PeerFixer class below will only be used
* if the Java 2 platform is used to deserialize ScrollPane objects that were serialized
* using JDK1.1
*/
/*
* serialVersionUID
*/
}
/**
* Invoked when the value of the adjustable has changed.
*/
}
switch(adj.getOrientation()) {
case Adjustable.VERTICAL:
break;
case Adjustable.HORIZONTAL:
break;
default:
throw new IllegalArgumentException("Illegal adjustable orientation");
}
}
}