JSplitPane is used to divide two (and only two)
+ * Components. The two Components
+ * are graphically divided based on the look and feel
+ * implementation, and the two Components can then be
+ * interactively resized by the user.
+ * Information on using JSplitPane is in
+ * How to Use Split Panes in
+ * The Java Tutorial.
+ *
+ * The two Components in a split pane can be aligned
+ * left to right using
+ * JSplitPane.HORIZONTAL_SPLIT, or top to bottom using
+ * JSplitPane.VERTICAL_SPLIT.
+ * The preferred way to change the size of the Components
+ * is to invoke
+ * setDividerLocation where location is either
+ * the new x or y position, depending on the orientation of the
+ * JSplitPane.
+ *
+ * To resize the Components to their preferred sizes invoke
+ * resetToPreferredSizes.
+ *
+ * When the user is resizing the Components the minimum
+ * size of the Components is used to determine the
+ * maximum/minimum position the Components
+ * can be set to. If the minimum size of the two
+ * components is greater than the size of the split pane the divider
+ * will not allow you to resize it. To alter the minimum size of a
+ * JComponent, see {@link JComponent#setMinimumSize}.
+ *
+ * When the user resizes the split pane the new space is distributed between
+ * the two components based on the resizeWeight property.
+ * A value of 0,
+ * the default, indicates the right/bottom component gets all the space,
+ * where as a value of 1 indicates the left/top component gets all the space.
+ *
+ * Warning: Swing is not thread safe. For more + * information see Swing's Threading + * Policy. + *
+ * Warning:
+ * Serialized objects of this class will not be compatible with
+ * future Swing releases. The current serialization support is
+ * appropriate for short term storage or RMI between applications running
+ * the same version of Swing. As of 1.4, support for long term storage
+ * of all JavaBeansTM
+ * has been added to the java.beans package.
+ * Please see {@link java.beans.XMLEncoder}.
+ *
+ * @see #setDividerLocation
+ * @see #resetToPreferredSizes
+ *
+ * @author Scott Violet
+ */
+public class JSplitPane extends JComponent implements Accessible
+{
+ /**
+ * @see #getUIClassID
+ * @see #readObject
+ */
+ private static final String uiClassID = "SplitPaneUI";
+
+ /**
+ * Vertical split indicates the Components are
+ * split along the y axis. For example the two
+ * Components will be split one on top of the other.
+ */
+ public final static int VERTICAL_SPLIT = 0;
+
+ /**
+ * Horizontal split indicates the Components are
+ * split along the x axis. For example the two
+ * Components will be split one to the left of the
+ * other.
+ */
+ public final static int HORIZONTAL_SPLIT = 1;
+
+ /**
+ * Used to add a Component to the left of the other
+ * Component.
+ */
+ public final static String LEFT = "left";
+
+ /**
+ * Used to add a Component to the right of the other
+ * Component.
+ */
+ public final static String RIGHT = "right";
+
+ /**
+ * Used to add a Component above the other
+ * Component.
+ */
+ public final static String TOP = "top";
+
+ /**
+ * Used to add a Component below the other
+ * Component.
+ */
+ public final static String BOTTOM = "bottom";
+
+ /**
+ * Used to add a Component that will represent the divider.
+ */
+ public final static String DIVIDER = "divider";
+
+ /**
+ * Bound property name for orientation (horizontal or vertical).
+ */
+ public final static String ORIENTATION_PROPERTY = "orientation";
+
+ /**
+ * Bound property name for continuousLayout.
+ */
+ public final static String CONTINUOUS_LAYOUT_PROPERTY = "continuousLayout";
+
+ /**
+ * Bound property name for border.
+ */
+ public final static String DIVIDER_SIZE_PROPERTY = "dividerSize";
+
+ /**
+ * Bound property for oneTouchExpandable.
+ */
+ public final static String ONE_TOUCH_EXPANDABLE_PROPERTY =
+ "oneTouchExpandable";
+
+ /**
+ * Bound property for lastLocation.
+ */
+ public final static String LAST_DIVIDER_LOCATION_PROPERTY =
+ "lastDividerLocation";
+
+ /**
+ * Bound property for the dividerLocation.
+ * @since 1.3
+ */
+ public final static String DIVIDER_LOCATION_PROPERTY = "dividerLocation";
+
+ /**
+ * Bound property for weight.
+ * @since 1.3
+ */
+ public final static String RESIZE_WEIGHT_PROPERTY = "resizeWeight";
+
+ /**
+ * How the views are split.
+ */
+ protected int orientation;
+
+ /**
+ * Whether or not the views are continuously redisplayed while
+ * resizing.
+ */
+ protected boolean continuousLayout;
+
+ /**
+ * The left or top component.
+ */
+ protected Component leftComponent;
+
+ /**
+ * The right or bottom component.
+ */
+ protected Component rightComponent;
+
+ /**
+ * Size of the divider.
+ */
+ protected int dividerSize;
+ private boolean dividerSizeSet = false;
+
+ /**
+ * Is a little widget provided to quickly expand/collapse the
+ * split pane?
+ */
+ protected boolean oneTouchExpandable;
+ private boolean oneTouchExpandableSet;
+
+ /**
+ * Previous location of the split pane.
+ */
+ protected int lastDividerLocation;
+
+ /**
+ * How to distribute extra space.
+ */
+ private double resizeWeight;
+
+ /**
+ * Location of the divider, at least the value that was set, the UI may
+ * have a different value.
+ */
+ private int dividerLocation;
+
+
+ /**
+ * Creates a new JSplitPane configured to arrange the child
+ * components side-by-side horizontally with no continuous
+ * layout, using two buttons for the components.
+ */
+ public JSplitPane() {
+ this(JSplitPane.HORIZONTAL_SPLIT, false,
+ new JButton(UIManager.getString("SplitPane.leftButtonText")),
+ new JButton(UIManager.getString("SplitPane.rightButtonText")));
+ }
+
+
+ /**
+ * Creates a new JSplitPane configured with the
+ * specified orientation and no continuous layout.
+ *
+ * @param newOrientation JSplitPane.HORIZONTAL_SPLIT or
+ * JSplitPane.VERTICAL_SPLIT
+ * @exception IllegalArgumentException if orientation
+ * is not one of HORIZONTAL_SPLIT or VERTICAL_SPLIT.
+ */
+ @ConstructorProperties({"orientation"})
+ public JSplitPane(int newOrientation) {
+ this(newOrientation, false);
+ }
+
+
+ /**
+ * Creates a new JSplitPane with the specified
+ * orientation and redrawing style.
+ *
+ * @param newOrientation JSplitPane.HORIZONTAL_SPLIT or
+ * JSplitPane.VERTICAL_SPLIT
+ * @param newContinuousLayout a boolean, true for the components to
+ * redraw continuously as the divider changes position, false
+ * to wait until the divider position stops changing to redraw
+ * @exception IllegalArgumentException if orientation
+ * is not one of HORIZONTAL_SPLIT or VERTICAL_SPLIT
+ */
+ public JSplitPane(int newOrientation,
+ boolean newContinuousLayout) {
+ this(newOrientation, newContinuousLayout, null, null);
+ }
+
+
+ /**
+ * Creates a new JSplitPane with the specified
+ * orientation and
+ * with the specified components that do not do continuous
+ * redrawing.
+ *
+ * @param newOrientation JSplitPane.HORIZONTAL_SPLIT or
+ * JSplitPane.VERTICAL_SPLIT
+ * @param newLeftComponent the Component that will
+ * appear on the left
+ * of a horizontally-split pane, or at the top of a
+ * vertically-split pane
+ * @param newRightComponent the Component that will
+ * appear on the right
+ * of a horizontally-split pane, or at the bottom of a
+ * vertically-split pane
+ * @exception IllegalArgumentException if orientation
+ * is not one of: HORIZONTAL_SPLIT or VERTICAL_SPLIT
+ */
+ public JSplitPane(int newOrientation,
+ Component newLeftComponent,
+ Component newRightComponent){
+ this(newOrientation, false, newLeftComponent, newRightComponent);
+ }
+
+
+ /**
+ * Creates a new JSplitPane with the specified
+ * orientation and
+ * redrawing style, and with the specified components.
+ *
+ * @param newOrientation JSplitPane.HORIZONTAL_SPLIT or
+ * JSplitPane.VERTICAL_SPLIT
+ * @param newContinuousLayout a boolean, true for the components to
+ * redraw continuously as the divider changes position, false
+ * to wait until the divider position stops changing to redraw
+ * @param newLeftComponent the Component that will
+ * appear on the left
+ * of a horizontally-split pane, or at the top of a
+ * vertically-split pane
+ * @param newRightComponent the Component that will
+ * appear on the right
+ * of a horizontally-split pane, or at the bottom of a
+ * vertically-split pane
+ * @exception IllegalArgumentException if orientation
+ * is not one of HORIZONTAL_SPLIT or VERTICAL_SPLIT
+ */
+ public JSplitPane(int newOrientation,
+ boolean newContinuousLayout,
+ Component newLeftComponent,
+ Component newRightComponent){
+ super();
+
+ dividerLocation = -1;
+ setLayout(null);
+ setUIProperty("opaque", Boolean.TRUE);
+ orientation = newOrientation;
+ if (orientation != HORIZONTAL_SPLIT && orientation != VERTICAL_SPLIT)
+ throw new IllegalArgumentException("cannot create JSplitPane, " +
+ "orientation must be one of " +
+ "JSplitPane.HORIZONTAL_SPLIT " +
+ "or JSplitPane.VERTICAL_SPLIT");
+ continuousLayout = newContinuousLayout;
+ if (newLeftComponent != null)
+ setLeftComponent(newLeftComponent);
+ if (newRightComponent != null)
+ setRightComponent(newRightComponent);
+ updateUI();
+
+ }
+
+
+ /**
+ * Sets the L&F object that renders this component.
+ *
+ * @param ui the SplitPaneUI L&F object
+ * @see UIDefaults#getUI
+ * @beaninfo
+ * bound: true
+ * hidden: true
+ * attribute: visualUpdate true
+ * description: The UI object that implements the Component's LookAndFeel.
+ */
+ public void setUI(SplitPaneUI ui) {
+ if ((SplitPaneUI)this.ui != ui) {
+ super.setUI(ui);
+ revalidate();
+ }
+ }
+
+
+ /**
+ * Returns the SplitPaneUI that is providing the
+ * current look and feel.
+ *
+ * @return the SplitPaneUI object that renders this component
+ * @beaninfo
+ * expert: true
+ * description: The L&F object that renders this component.
+ */
+ public SplitPaneUI getUI() {
+ return (SplitPaneUI)ui;
+ }
+
+
+ /**
+ * Notification from the UIManager that the L&F has changed.
+ * Replaces the current UI object with the latest version from the
+ * UIManager.
+ *
+ * @see JComponent#updateUI
+ */
+ public void updateUI() {
+ setUI((SplitPaneUI)UIManager.getUI(this));
+ revalidate();
+ }
+
+
+ /**
+ * Returns the name of the L&F class that renders this component.
+ *
+ * @return the string "SplitPaneUI"
+ * @see JComponent#getUIClassID
+ * @see UIDefaults#getUI
+ * @beaninfo
+ * expert: true
+ * description: A string that specifies the name of the L&F class.
+ */
+ public String getUIClassID() {
+ return uiClassID;
+ }
+
+
+ /**
+ * Sets the size of the divider.
+ *
+ * @param newSize an integer giving the size of the divider in pixels
+ * @beaninfo
+ * bound: true
+ * description: The size of the divider.
+ */
+ public void setDividerSize(int newSize) {
+ int oldSize = dividerSize;
+
+ dividerSizeSet = true;
+ if (oldSize != newSize) {
+ dividerSize = newSize;
+ firePropertyChange(DIVIDER_SIZE_PROPERTY, oldSize, newSize);
+ }
+ }
+
+
+ /**
+ * Returns the size of the divider.
+ *
+ * @return an integer giving the size of the divider in pixels
+ */
+ public int getDividerSize() {
+ return dividerSize;
+ }
+
+
+ /**
+ * Sets the component to the left (or above) the divider.
+ *
+ * @param comp the Component to display in that position
+ */
+ public void setLeftComponent(Component comp) {
+ if (comp == null) {
+ if (leftComponent != null) {
+ remove(leftComponent);
+ leftComponent = null;
+ }
+ } else {
+ add(comp, JSplitPane.LEFT);
+ }
+ }
+
+
+ /**
+ * Returns the component to the left (or above) the divider.
+ *
+ * @return the Component displayed in that position
+ * @beaninfo
+ * preferred: true
+ * description: The component to the left (or above) the divider.
+ */
+ public Component getLeftComponent() {
+ return leftComponent;
+ }
+
+
+ /**
+ * Sets the component above, or to the left of the divider.
+ *
+ * @param comp the Component to display in that position
+ * @beaninfo
+ * description: The component above, or to the left of the divider.
+ */
+ public void setTopComponent(Component comp) {
+ setLeftComponent(comp);
+ }
+
+
+ /**
+ * Returns the component above, or to the left of the divider.
+ *
+ * @return the Component displayed in that position
+ */
+ public Component getTopComponent() {
+ return leftComponent;
+ }
+
+
+ /**
+ * Sets the component to the right (or below) the divider.
+ *
+ * @param comp the Component to display in that position
+ * @beaninfo
+ * preferred: true
+ * description: The component to the right (or below) the divider.
+ */
+ public void setRightComponent(Component comp) {
+ if (comp == null) {
+ if (rightComponent != null) {
+ remove(rightComponent);
+ rightComponent = null;
+ }
+ } else {
+ add(comp, JSplitPane.RIGHT);
+ }
+ }
+
+
+ /**
+ * Returns the component to the right (or below) the divider.
+ *
+ * @return the Component displayed in that position
+ */
+ public Component getRightComponent() {
+ return rightComponent;
+ }
+
+
+ /**
+ * Sets the component below, or to the right of the divider.
+ *
+ * @param comp the Component to display in that position
+ * @beaninfo
+ * description: The component below, or to the right of the divider.
+ */
+ public void setBottomComponent(Component comp) {
+ setRightComponent(comp);
+ }
+
+
+ /**
+ * Returns the component below, or to the right of the divider.
+ *
+ * @return the Component displayed in that position
+ */
+ public Component getBottomComponent() {
+ return rightComponent;
+ }
+
+
+ /**
+ * Sets the value of the oneTouchExpandable property,
+ * which must be true for the
+ * JSplitPane to provide a UI widget
+ * on the divider to quickly expand/collapse the divider.
+ * The default value of this property is false.
+ * Some look and feels might not support one-touch expanding;
+ * they will ignore this property.
+ *
+ * @param newValue true to specify that the split pane should provide a
+ * collapse/expand widget
+ * @beaninfo
+ * bound: true
+ * description: UI widget on the divider to quickly
+ * expand/collapse the divider.
+ *
+ * @see #isOneTouchExpandable
+ */
+ public void setOneTouchExpandable(boolean newValue) {
+ boolean oldValue = oneTouchExpandable;
+
+ oneTouchExpandable = newValue;
+ oneTouchExpandableSet = true;
+ firePropertyChange(ONE_TOUCH_EXPANDABLE_PROPERTY, oldValue, newValue);
+ repaint();
+ }
+
+
+ /**
+ * Gets the oneTouchExpandable property.
+ *
+ * @return the value of the oneTouchExpandable property
+ * @see #setOneTouchExpandable
+ */
+ public boolean isOneTouchExpandable() {
+ return oneTouchExpandable;
+ }
+
+
+ /**
+ * Sets the last location the divider was at to
+ * newLastLocation.
+ *
+ * @param newLastLocation an integer specifying the last divider location
+ * in pixels, from the left (or upper) edge of the pane to the
+ * left (or upper) edge of the divider
+ * @beaninfo
+ * bound: true
+ * description: The last location the divider was at.
+ */
+ public void setLastDividerLocation(int newLastLocation) {
+ int oldLocation = lastDividerLocation;
+
+ lastDividerLocation = newLastLocation;
+ firePropertyChange(LAST_DIVIDER_LOCATION_PROPERTY, oldLocation,
+ newLastLocation);
+ }
+
+
+ /**
+ * Returns the last location the divider was at.
+ *
+ * @return an integer specifying the last divider location as a count
+ * of pixels from the left (or upper) edge of the pane to the
+ * left (or upper) edge of the divider
+ */
+ public int getLastDividerLocation() {
+ return lastDividerLocation;
+ }
+
+
+ /**
+ * Sets the orientation, or how the splitter is divided. The options
+ * are:
continuousLayout property,
+ * which must be true for the child components
+ * to be continuously
+ * redisplayed and laid out during user intervention.
+ * The default value of this property is false.
+ * Some look and feels might not support continuous layout;
+ * they will ignore this property.
+ *
+ * @param newContinuousLayout true if the components
+ * should continuously be redrawn as the divider changes position
+ * @beaninfo
+ * bound: true
+ * description: Whether the child components are
+ * continuously redisplayed and laid out during
+ * user intervention.
+ * @see #isContinuousLayout
+ */
+ public void setContinuousLayout(boolean newContinuousLayout) {
+ boolean oldCD = continuousLayout;
+
+ continuousLayout = newContinuousLayout;
+ firePropertyChange(CONTINUOUS_LAYOUT_PROPERTY, oldCD,
+ newContinuousLayout);
+ }
+
+
+ /**
+ * Gets the continuousLayout property.
+ *
+ * @return the value of the continuousLayout property
+ * @see #setContinuousLayout
+ */
+ public boolean isContinuousLayout() {
+ return continuousLayout;
+ }
+
+ /**
+ * Specifies how to distribute extra space when the size of the split pane
+ * changes. A value of 0, the default,
+ * indicates the right/bottom component gets all the extra space (the
+ * left/top component acts fixed), where as a value of 1 specifies the
+ * left/top component gets all the extra space (the right/bottom component
+ * acts fixed). Specifically, the left/top component gets (weight * diff)
+ * extra space and the right/bottom component gets (1 - weight) * diff
+ * extra space.
+ *
+ * @param value as described above
+ * @exception IllegalArgumentException if value is < 0 or > 1
+ * @since 1.3
+ * @beaninfo
+ * bound: true
+ * description: Specifies how to distribute extra space when the split pane
+ * resizes.
+ */
+ public void setResizeWeight(double value) {
+ if (value < 0 || value > 1) {
+ throw new IllegalArgumentException("JSplitPane weight must be between 0 and 1");
+ }
+ double oldWeight = resizeWeight;
+
+ resizeWeight = value;
+ firePropertyChange(RESIZE_WEIGHT_PROPERTY, oldWeight, value);
+ }
+
+ /**
+ * Returns the number that determines how extra space is distributed.
+ * @return how extra space is to be distributed on a resize of the
+ * split pane
+ * @since 1.3
+ */
+ public double getResizeWeight() {
+ return resizeWeight;
+ }
+
+ /**
+ * Lays out the JSplitPane layout based on the preferred size
+ * of the children components. This will likely result in changing
+ * the divider location.
+ */
+ public void resetToPreferredSizes() {
+ SplitPaneUI ui = getUI();
+
+ if (ui != null) {
+ ui.resetToPreferredSizes(this);
+ }
+ }
+
+
+ /**
+ * Sets the divider location as a percentage of the
+ * JSplitPane's size.
+ *
+ * This method is implemented in terms of
+ * setDividerLocation(int).
+ * This method immediately changes the size of the split pane based on
+ * its current size. If the split pane is not correctly realized and on
+ * screen, this method will have no effect (new divider location will
+ * become (current size * proportionalLocation) which is 0).
+ *
+ * @param proportionalLocation a double-precision floating point value
+ * that specifies a percentage, from zero (top/left) to 1.0
+ * (bottom/right)
+ * @exception IllegalArgumentException if the specified location is < 0
+ * or > 1.0
+ * @beaninfo
+ * description: The location of the divider.
+ */
+ public void setDividerLocation(double proportionalLocation) {
+ if (proportionalLocation < 0.0 ||
+ proportionalLocation > 1.0) {
+ throw new IllegalArgumentException("proportional location must " +
+ "be between 0.0 and 1.0.");
+ }
+ if (getOrientation() == VERTICAL_SPLIT) {
+ setDividerLocation((int)((double)(getHeight() - getDividerSize()) *
+ proportionalLocation));
+ } else {
+ setDividerLocation((int)((double)(getWidth() - getDividerSize()) *
+ proportionalLocation));
+ }
+ }
+
+
+ /**
+ * Sets the location of the divider. This is passed off to the
+ * look and feel implementation, and then listeners are notified. A value
+ * less than 0 implies the divider should be reset to a value that
+ * attempts to honor the preferred size of the left/top component.
+ * After notifying the listeners, the last divider location is updated,
+ * via setLastDividerLocation.
+ *
+ * @param location an int specifying a UI-specific value (typically a
+ * pixel count)
+ * @beaninfo
+ * bound: true
+ * description: The location of the divider.
+ */
+ public void setDividerLocation(int location) {
+ int oldValue = dividerLocation;
+
+ dividerLocation = location;
+
+ // Notify UI.
+ SplitPaneUI ui = getUI();
+
+ if (ui != null) {
+ ui.setDividerLocation(this, location);
+ }
+
+ // Then listeners
+ firePropertyChange(DIVIDER_LOCATION_PROPERTY, oldValue, location);
+
+ // And update the last divider location.
+ setLastDividerLocation(oldValue);
+ }
+
+
+ /**
+ * Returns the last value passed to setDividerLocation.
+ * The value returned from this method may differ from the actual
+ * divider location (if setDividerLocation was passed a
+ * value bigger than the curent size).
+ *
+ * @return an integer specifying the location of the divider
+ */
+ public int getDividerLocation() {
+ return dividerLocation;
+ }
+
+
+ /**
+ * Returns the minimum location of the divider from the look and feel
+ * implementation.
+ *
+ * @return an integer specifying a UI-specific value for the minimum
+ * location (typically a pixel count); or -1 if the UI is
+ * null
+ * @beaninfo
+ * description: The minimum location of the divider from the L&F.
+ */
+ public int getMinimumDividerLocation() {
+ SplitPaneUI ui = getUI();
+
+ if (ui != null) {
+ return ui.getMinimumDividerLocation(this);
+ }
+ return -1;
+ }
+
+
+ /**
+ * Returns the maximum location of the divider from the look and feel
+ * implementation.
+ *
+ * @return an integer specifying a UI-specific value for the maximum
+ * location (typically a pixel count); or -1 if the UI is
+ * null
+ */
+ public int getMaximumDividerLocation() {
+ SplitPaneUI ui = getUI();
+
+ if (ui != null) {
+ return ui.getMaximumDividerLocation(this);
+ }
+ return -1;
+ }
+
+
+ /**
+ * Removes the child component, component from the
+ * pane. Resets the leftComponent or
+ * rightComponent instance variable, as necessary.
+ *
+ * @param component the Component to remove
+ */
+ public void remove(Component component) {
+ if (component == leftComponent) {
+ leftComponent = null;
+ } else if (component == rightComponent) {
+ rightComponent = null;
+ }
+ super.remove(component);
+
+ // Update the JSplitPane on the screen
+ revalidate();
+ repaint();
+ }
+
+
+ /**
+ * Removes the Component at the specified index.
+ * Updates the leftComponent and rightComponent
+ * instance variables as necessary, and then messages super.
+ *
+ * @param index an integer specifying the component to remove, where
+ * 1 specifies the left/top component and 2 specifies the
+ * bottom/right component
+ */
+ public void remove(int index) {
+ Component comp = getComponent(index);
+
+ if (comp == leftComponent) {
+ leftComponent = null;
+ } else if (comp == rightComponent) {
+ rightComponent = null;
+ }
+ super.remove(index);
+
+ // Update the JSplitPane on the screen
+ revalidate();
+ repaint();
+ }
+
+
+ /**
+ * Removes all the child components from the split pane. Resets the
+ * leftComonent and rightComponent
+ * instance variables.
+ */
+ public void removeAll() {
+ leftComponent = rightComponent = null;
+ super.removeAll();
+
+ // Update the JSplitPane on the screen
+ revalidate();
+ repaint();
+ }
+
+
+ /**
+ * Returns true, so that calls to revalidate
+ * on any descendant of this JSplitPane
+ * will cause a request to be queued that
+ * will validate the JSplitPane and all its descendants.
+ *
+ * @return true
+ * @see JComponent#revalidate
+ *
+ * @beaninfo
+ * hidden: true
+ */
+ public boolean isValidateRoot() {
+ return true;
+ }
+
+
+ /**
+ * Adds the specified component to this split pane.
+ * If constraints identifies the left/top or
+ * right/bottom child component, and a component with that identifier
+ * was previously added, it will be removed and then comp
+ * will be added in its place. If constraints is not
+ * one of the known identifiers the layout manager may throw an
+ * IllegalArgumentException.
+ *
+ * The possible constraints objects (Strings) are: + *
constraints object is null,
+ * the component is added in the
+ * first available position (left/top if open, else right/bottom).
+ *
+ * @param comp the component to add
+ * @param constraints an Object specifying the
+ * layout constraints
+ * (position) for this component
+ * @param index an integer specifying the index in the container's
+ * list.
+ * @exception IllegalArgumentException if the constraints
+ * object does not match an existing component
+ * @see java.awt.Container#addImpl(Component, Object, int)
+ */
+ protected void addImpl(Component comp, Object constraints, int index)
+ {
+ Component toRemove;
+
+ if (constraints != null && !(constraints instanceof String)) {
+ throw new IllegalArgumentException("cannot add to layout: " +
+ "constraint must be a string " +
+ "(or null)");
+ }
+
+ /* If the constraints are null and the left/right component is
+ invalid, add it at the left/right component. */
+ if (constraints == null) {
+ if (getLeftComponent() == null) {
+ constraints = JSplitPane.LEFT;
+ } else if (getRightComponent() == null) {
+ constraints = JSplitPane.RIGHT;
+ }
+ }
+
+ /* Find the Component that already exists and remove it. */
+ if (constraints != null && (constraints.equals(JSplitPane.LEFT) ||
+ constraints.equals(JSplitPane.TOP))) {
+ toRemove = getLeftComponent();
+ if (toRemove != null) {
+ remove(toRemove);
+ }
+ leftComponent = comp;
+ index = -1;
+ } else if (constraints != null &&
+ (constraints.equals(JSplitPane.RIGHT) ||
+ constraints.equals(JSplitPane.BOTTOM))) {
+ toRemove = getRightComponent();
+ if (toRemove != null) {
+ remove(toRemove);
+ }
+ rightComponent = comp;
+ index = -1;
+ } else if (constraints != null &&
+ constraints.equals(JSplitPane.DIVIDER)) {
+ index = -1;
+ }
+ /* LayoutManager should raise for else condition here. */
+
+ super.addImpl(comp, constraints, index);
+
+ // Update the JSplitPane on the screen
+ revalidate();
+ repaint();
+ }
+
+
+ /**
+ * Subclassed to message the UI with finishedPaintingChildren
+ * after super has been messaged, as well as painting the border.
+ *
+ * @param g the Graphics context within which to paint
+ */
+ protected void paintChildren(Graphics g) {
+ super.paintChildren(g);
+
+ SplitPaneUI ui = getUI();
+
+ if (ui != null) {
+ Graphics tempG = g.create();
+ ui.finishedPaintingChildren(this, tempG);
+ tempG.dispose();
+ }
+ }
+
+
+ /**
+ * See readObject and writeObject in
+ * JComponent for more
+ * information about serialization in Swing.
+ */
+ private void writeObject(ObjectOutputStream s) throws IOException {
+ s.defaultWriteObject();
+ if (getUIClassID().equals(uiClassID)) {
+ byte count = JComponent.getWriteObjCounter(this);
+ JComponent.setWriteObjCounter(this, --count);
+ if (count == 0 && ui != null) {
+ ui.installUI(this);
+ }
+ }
+ }
+
+ void setUIProperty(String propertyName, Object value) {
+ if (propertyName == "dividerSize") {
+ if (!dividerSizeSet) {
+ setDividerSize(((Number)value).intValue());
+ dividerSizeSet = false;
+ }
+ } else if (propertyName == "oneTouchExpandable") {
+ if (!oneTouchExpandableSet) {
+ setOneTouchExpandable(((Boolean)value).booleanValue());
+ oneTouchExpandableSet = false;
+ }
+ } else {
+ super.setUIProperty(propertyName, value);
+ }
+ }
+
+
+ /**
+ * Returns a string representation of this JSplitPane.
+ * 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 null.
+ *
+ * @return a string representation of this JSplitPane.
+ */
+ protected String paramString() {
+ String orientationString = (orientation == HORIZONTAL_SPLIT ?
+ "HORIZONTAL_SPLIT" : "VERTICAL_SPLIT");
+ String continuousLayoutString = (continuousLayout ?
+ "true" : "false");
+ String oneTouchExpandableString = (oneTouchExpandable ?
+ "true" : "false");
+
+ return super.paramString() +
+ ",continuousLayout=" + continuousLayoutString +
+ ",dividerSize=" + dividerSize +
+ ",lastDividerLocation=" + lastDividerLocation +
+ ",oneTouchExpandable=" + oneTouchExpandableString +
+ ",orientation=" + orientationString;
+ }
+
+
+
+ ///////////////////////////
+ // Accessibility support //
+ ///////////////////////////
+
+
+ /**
+ * Gets the AccessibleContext associated with this JSplitPane.
+ * For split panes, the AccessibleContext takes the form of an
+ * AccessibleJSplitPane.
+ * A new AccessibleJSplitPane instance is created if necessary.
+ *
+ * @return an AccessibleJSplitPane that serves as the
+ * AccessibleContext of this JSplitPane
+ * @beaninfo
+ * expert: true
+ * description: The AccessibleContext associated with this SplitPane.
+ */
+ public AccessibleContext getAccessibleContext() {
+ if (accessibleContext == null) {
+ accessibleContext = new AccessibleJSplitPane();
+ }
+ return accessibleContext;
+ }
+
+
+ /**
+ * This class implements accessibility support for the
+ * JSplitPane class. It provides an implementation of the
+ * Java Accessibility API appropriate to split pane user-interface elements.
+ *
+ * Warning:
+ * Serialized objects of this class will not be compatible with
+ * future Swing releases. The current serialization support is
+ * appropriate for short term storage or RMI between applications running
+ * the same version of Swing. As of 1.4, support for long term storage
+ * of all JavaBeansTM
+ * has been added to the java.beans package.
+ * Please see {@link java.beans.XMLEncoder}.
+ */
+ protected class AccessibleJSplitPane extends AccessibleJComponent
+ implements AccessibleValue {
+ /**
+ * Gets the state set of this object.
+ *
+ * @return an instance of AccessibleState containing the current state
+ * of the object
+ * @see AccessibleState
+ */
+ public AccessibleStateSet getAccessibleStateSet() {
+ AccessibleStateSet states = super.getAccessibleStateSet();
+ // FIXME: [[[WDW - Should also add BUSY if this implements
+ // Adjustable at some point. If this happens, we probably
+ // should also add actions.]]]
+ if (getOrientation() == VERTICAL_SPLIT) {
+ states.add(AccessibleState.VERTICAL);
+ } else {
+ states.add(AccessibleState.HORIZONTAL);
+ }
+ return states;
+ }
+
+
+ /**
+ * Get the AccessibleValue associated with this object. In the
+ * implementation of the Java Accessibility API for this class,
+ * return this object, which is responsible for implementing the
+ * AccessibleValue interface on behalf of itself.
+ *
+ * @return this object
+ */
+ public AccessibleValue getAccessibleValue() {
+ return this;
+ }
+
+
+ /**
+ * Gets the accessible value of this object.
+ *
+ * @return a localized String describing the value of this object
+ */
+ public Number getCurrentAccessibleValue() {
+ return new Integer(getDividerLocation());
+ }
+
+
+ /**
+ * Sets the value of this object as a Number.
+ *
+ * @return True if the value was set.
+ */
+ public boolean setCurrentAccessibleValue(Number n) {
+ // TIGER - 4422535
+ if (n == null) {
+ return false;
+ }
+ setDividerLocation(n.intValue());
+ return true;
+ }
+
+
+ /**
+ * Gets the minimum accessible value of this object.
+ *
+ * @return The minimum value of this object.
+ */
+ public Number getMinimumAccessibleValue() {
+ return new Integer(getUI().getMinimumDividerLocation(
+ JSplitPane.this));
+ }
+
+
+ /**
+ * Gets the maximum accessible value of this object.
+ *
+ * @return The maximum value of this object.
+ */
+ public Number getMaximumAccessibleValue() {
+ return new Integer(getUI().getMaximumDividerLocation(
+ JSplitPane.this));
+ }
+
+
+ /**
+ * Gets the role of this object.
+ *
+ * @return an instance of AccessibleRole describing the role of
+ * the object
+ * @see AccessibleRole
+ */
+ public AccessibleRole getAccessibleRole() {
+ return AccessibleRole.SPLIT_PANE;
+ }
+ } // inner class AccessibleJSplitPane
+}