libjava/java/awt/ScrollPane.java - gcc - Git at Google

 /* Copyright (C) 2000  Free Software Foundation

    This file is part of libgcj.

 This software is copyrighted work licensed under the terms of the
 Libgcj License.  Please consult the file "LIBGCJ_LICENSE" for
 details.  */

 package java.awt;

 import java.awt.event.AdjustmentListener;
 import java.awt.peer.ScrollPanePeer;

 /** A ScrollPane is a component that has vertical and horizontal
  * scrollbars as well as a single child which is scrolled by them.
  * @author Tom Tromey <tromey@redhat.com>
  * @date December 31, 2000
  */
 public class ScrollPane extends Container
 {
   /** This indicates that scrollbars should only be displayed when
    * needed.  */
   public static final int SCROLLBARS_AS_NEEDED = 0;
   /** This indicates that scrollbars should always be displayed.  */
   public static final int SCROLLBARS_ALWAYS = 1;
   /** This indicates that scrollbars should never be displayed.  */
   public static final int SCROLLBARS_NEVER = 2;

   /** Create a new ScrollPane object using the indicated scrollbar
    * display policy.  If the policy is not specified it defaults to
    * SCROLLBARS_AS_NEEDED.  The default size of this component is
    * 100x100.
    * @param policy The scrollbar display policy
    */
   public ScrollPane ()
   {
     this (SCROLLBARS_AS_NEEDED);
   }

   public ScrollPane (int policy)
   {
     if (policy != SCROLLBARS_AS_NEEDED
 	&& policy != SCROLLBARS_ALWAYS
 	&& policy != SCROLLBARS_NEVER)
       throw new IllegalArgumentException ("invalid value for policy");

     this.policy = policy;
     setSize (100, 100);
   }

   /** Add a component to this ScrollPane.
    * @param comp The component to add
    * @param constraints Constraints.  This is ignored.
    * @param pos Position.  This must be <= 0, but is otherwise ignored.
    */
   protected final void addImpl (Component comp, Object constraints,
 				int pos)
   {
     if (pos > 0)
       throw new IllegalArgumentException ("pos must be <= 0");

     if (ncomponents > 0)
       remove (component[0]);

     if (comp.isLightweight ())
       {
 	Panel p = new Panel ();
 	p.add (comp);
 	comp = p;
       }

     super.addImpl (comp, constraints, pos);
   }

   /** This creates the component's peer.  */
   public void addNotify ()
   {
     if (peer == null)
       peer = getToolkit ().createScrollPane (this);
     super.addNotify ();
   }

   /** Lays out the components in this container.  */
   public void doLayout ()
   {
     ScrollPanePeer spp = (ScrollPanePeer) peer;
     Dimension c = component[0].getPreferredSize ();
     component[0].setSize (c.width, c.height);
     spp.childResized (c.width, c.height);
     // Update the scrollbar position to the closest valid value.
     setScrollPosition (hscroll.getValue (), vscroll.getValue ());
   }

   /** Returns an Adjustable representing the horizontal scrollbar.
    * The methods setMaximum, setMinimum, and setVisibleAmount should
    * not be called on this Adjustable.  They will throw AWTError if
    * called.
    */
   public Adjustable getHAdjustable ()
   {
     return hscroll;
   }

   /** Returns the height of the horizontal scrollbar.  */
   public int getHScrollbarHeight ()
   {
     if (peer == null)
       return 0;
     ScrollPanePeer spp = (ScrollPanePeer) peer;
     return spp.getHScrollbarHeight ();
   }

   /** Returns the scrollbar display policy.  */
   public int getScrollbarDisplayPolicy ()
   {
     return policy;
   }

   /** Returns the viewport's scroll position.  */
   public Point getScrollPosition ()
   {
     return new Point (hscroll.getValue (), vscroll.getValue ());
   }

   /** Returns an Adjustable representing the vertical scrollbar.
    * The methods setMaximum, setMinimum, and setVisibleAmount should
    * not be called on this Adjustable.  They will throw AWTError if
    * called.
    */
   public Adjustable getVAdjustable ()
   {
     return vscroll;
   }

   /** Returns the size of the viewport.  */
   public Dimension getViewportSize ()
   {
     // Note: according to the online docs, the Insets are
     // automatically updated by the peer to include the scrollbar
     // sizes.
     Insets ins = getInsets ();
     int myw = width - ins.left - ins.right;
     int myh = height - ins.top - ins.bottom;

     Dimension cs;
     if (ncomponents > 0)
       cs = component[0].getPreferredSize ();
     else
       cs = new Dimension (myw, myh);

     // A little optimization -- reuse the Dimension.
     cs.setSize (myw, myh);
     return cs;
   }

   /** Returns the width of the vertical scrollbar.  */
   public int getVScrollbarWidth ()
   {
     if (peer == null)
       return 0;
     ScrollPanePeer spp = (ScrollPanePeer) peer;
     return spp.getVScrollbarWidth ();
   }

   /** Generates a String representation of this ScrollPane's state.  */
   public String paramString ()
   {
     return ("[" + getClass ().getName ()
 	    + ": " + ((ncomponents > 0) ? component[0].paramString () : "")
 	    + "]");
   }

   /** Set the layout manager for this component.  ScrollPane has its
    * own layout manager and overrides this method so that the layout
    * manager cannot be changed.
    * @param m The new layout manager (ignored)
    */
   public final void setLayout (LayoutManager m)
   {
     // Nothing.
   }

   /** Sets the scroll position for this ScrollPane.  If the point if
    * out of range it is silently moved within range.
    * @param x The x coordinate
    * @param y The y coordinate
    */
   public void setScrollPosition (int x, int y)
   {
     // According to the JCL we throw a NullPointerException if there
     // is no child.
     if (ncomponents == 0)
       throw new NullPointerException ("no child in ScrollPane");

     Dimension child_d = component[0].getPreferredSize ();
     Dimension our_d = getViewportSize ();

     int xmax = Math.max (0, child_d.width - our_d.width);
     int ymax = Math.max (0, child_d.height - our_d.height);

     if (x < 0)
       x = 0;
     else if (x > xmax)
       x = xmax;
     if (y < 0)
       y = 0;
     else if (y > ymax)
       y = ymax;

     ScrollPanePeer spp = (ScrollPanePeer) peer;
     spp.setScrollPosition (x, y);
   }

   /** Sets the scroll position for this ScrollPane.  If the point if
    * out of range it is silently moved within range.
    * @param p The new point
    */
   public void setScrollPosition (Point p)
   {
     setScrollPosition (p.x, p.y);
   }

   // This implements the Adjustable for each scrollbar.  The
   // expectation is that the peer will look at these objects directly
   // and modify the values in them when the user manipulates the
   // scrollbars.  This has to be done from CNI to bypass Java
   // protection rules.  The peer should also take care of calling the
   // adjustment listeners.
   class ScrollPaneAdjustable implements Adjustable
   {
     AdjustmentListener listeners;
     int orient;
     int unit;
     int block;
     int value;

     public ScrollPaneAdjustable (int orient)
     {
       this.orient = orient;
     }

     public void addAdjustmentListener (AdjustmentListener l)
     {
       listeners = AWTEventMulticaster.add (listeners, l);
     }

     public int getBlockIncrement ()
     {
       return block;
     }

     public int getMaximum ()
     {
       Dimension child_d = component[0].getPreferredSize ();
       Dimension our_d = getViewportSize ();

       int xmax = Math.max (0, child_d.width - our_d.width);
       int ymax = Math.max (0, child_d.height - our_d.height);

       return (orient == Adjustable.HORIZONTAL) ? xmax : ymax;
     }

     public int getMinimum ()
     {
       return 0;
     }

     public int getOrientation ()
     {
       return orient;
     }

     public int getUnitIncrement ()
     {
       return unit;
     }

     public int getValue ()
     {
       return value;
     }

     public int getVisibleAmount ()
     {
       Dimension d = getViewportSize ();
       return (orient == Adjustable.HORIZONTAL) ? d.width : d.height;
     }

     public void removeAdjustmentListener (AdjustmentListener l)
     {
       listeners = AWTEventMulticaster.remove (listeners, l);
     }

     public void setBlockIncrement (int b)
     {
       throw new AWTError ("can't use setBlockIncrement on this Adjustable");
     }

     public void setMaximum (int max)
     {
       throw new AWTError ("can't use setMaximum on this Adjustable");
     }

     public void setMinimum (int min)
     {
       throw new AWTError ("can't use setMinimum on this Adjustable");
     }

     public void setUnitIncrement (int u)
     {
       unit = u;
       if (peer != null)
 	{
 	  ScrollPanePeer spp = (ScrollPanePeer) peer;
 	  spp.setUnitIncrement (this, u);
 	}
     }

     public void setValue (int v)
     {
       value = v;
       if (peer != null)
 	{
 	  ScrollPanePeer spp = (ScrollPanePeer) peer;
 	  spp.setValue (this, v);
 	}
     }

     public void setVisibleAmount (int v)
     {
       throw new AWTError ("can't use setVisibleAmount on this Adjustable");
     }
   }

   ScrollPaneAdjustable hscroll
     = new ScrollPaneAdjustable (Adjustable.HORIZONTAL);
   ScrollPaneAdjustable vscroll
     = new ScrollPaneAdjustable (Adjustable.VERTICAL);
   int policy;
 }
	/* Copyright (C) 2000 Free Software Foundation

	This file is part of libgcj.

	This software is copyrighted work licensed under the terms of the
	Libgcj License. Please consult the file "LIBGCJ_LICENSE" for
	details. */

	package java.awt;

	import java.awt.event.AdjustmentListener;
	import java.awt.peer.ScrollPanePeer;

	/** A ScrollPane is a component that has vertical and horizontal
	* scrollbars as well as a single child which is scrolled by them.
	* @author Tom Tromey <tromey@redhat.com>
	* @date December 31, 2000
	*/
	public class ScrollPane extends Container
	{
	/** This indicates that scrollbars should only be displayed when
	* needed. */
	public static final int SCROLLBARS_AS_NEEDED = 0;
	/** This indicates that scrollbars should always be displayed. */
	public static final int SCROLLBARS_ALWAYS = 1;
	/** This indicates that scrollbars should never be displayed. */
	public static final int SCROLLBARS_NEVER = 2;

	/** Create a new ScrollPane object using the indicated scrollbar
	* display policy. If the policy is not specified it defaults to
	* SCROLLBARS_AS_NEEDED. The default size of this component is
	* 100x100.
	* @param policy The scrollbar display policy
	*/
	public ScrollPane ()
	{
	this (SCROLLBARS_AS_NEEDED);
	}

	public ScrollPane (int policy)
	{
	if (policy != SCROLLBARS_AS_NEEDED
	&& policy != SCROLLBARS_ALWAYS
	&& policy != SCROLLBARS_NEVER)
	throw new IllegalArgumentException ("invalid value for policy");

	this.policy = policy;
	setSize (100, 100);
	}

	/** Add a component to this ScrollPane.
	* @param comp The component to add
	* @param constraints Constraints. This is ignored.
	* @param pos Position. This must be <= 0, but is otherwise ignored.
	*/
	protected final void addImpl (Component comp, Object constraints,
	int pos)
	{
	if (pos > 0)
	throw new IllegalArgumentException ("pos must be <= 0");

	if (ncomponents > 0)
	remove (component[0]);

	if (comp.isLightweight ())
	{
	Panel p = new Panel ();
	p.add (comp);
	comp = p;
	}

	super.addImpl (comp, constraints, pos);
	}

	/** This creates the component's peer. */
	public void addNotify ()
	{
	if (peer == null)
	peer = getToolkit ().createScrollPane (this);
	super.addNotify ();
	}

	/** Lays out the components in this container. */
	public void doLayout ()
	{
	ScrollPanePeer spp = (ScrollPanePeer) peer;
	Dimension c = component[0].getPreferredSize ();
	component[0].setSize (c.width, c.height);
	spp.childResized (c.width, c.height);
	// Update the scrollbar position to the closest valid value.
	setScrollPosition (hscroll.getValue (), vscroll.getValue ());
	}

	/** Returns an Adjustable representing the horizontal scrollbar.
	* The methods setMaximum, setMinimum, and setVisibleAmount should
	* not be called on this Adjustable. They will throw AWTError if
	* called.
	*/
	public Adjustable getHAdjustable ()
	{
	return hscroll;
	}

	/** Returns the height of the horizontal scrollbar. */
	public int getHScrollbarHeight ()
	{
	if (peer == null)
	return 0;
	ScrollPanePeer spp = (ScrollPanePeer) peer;
	return spp.getHScrollbarHeight ();
	}

	/** Returns the scrollbar display policy. */
	public int getScrollbarDisplayPolicy ()
	{
	return policy;
	}

	/** Returns the viewport's scroll position. */
	public Point getScrollPosition ()
	{
	return new Point (hscroll.getValue (), vscroll.getValue ());
	}

	/** Returns an Adjustable representing the vertical scrollbar.
	* The methods setMaximum, setMinimum, and setVisibleAmount should
	* not be called on this Adjustable. They will throw AWTError if
	* called.
	*/
	public Adjustable getVAdjustable ()
	{
	return vscroll;
	}

	/** Returns the size of the viewport. */
	public Dimension getViewportSize ()
	{
	// Note: according to the online docs, the Insets are
	// automatically updated by the peer to include the scrollbar
	// sizes.
	Insets ins = getInsets ();
	int myw = width - ins.left - ins.right;
	int myh = height - ins.top - ins.bottom;

	Dimension cs;
	if (ncomponents > 0)
	cs = component[0].getPreferredSize ();
	else
	cs = new Dimension (myw, myh);

	// A little optimization -- reuse the Dimension.
	cs.setSize (myw, myh);
	return cs;
	}

	/** Returns the width of the vertical scrollbar. */
	public int getVScrollbarWidth ()
	{
	if (peer == null)
	return 0;
	ScrollPanePeer spp = (ScrollPanePeer) peer;
	return spp.getVScrollbarWidth ();
	}

	/** Generates a String representation of this ScrollPane's state. */
	public String paramString ()
	{
	return ("[" + getClass ().getName ()
	+ ": " + ((ncomponents > 0) ? component[0].paramString () : "")
	+ "]");
	}

	/** Set the layout manager for this component. ScrollPane has its
	* own layout manager and overrides this method so that the layout
	* manager cannot be changed.
	* @param m The new layout manager (ignored)
	*/
	public final void setLayout (LayoutManager m)
	{
	// Nothing.
	}

	/** Sets the scroll position for this ScrollPane. If the point if
	* out of range it is silently moved within range.
	* @param x The x coordinate
	* @param y The y coordinate
	*/
	public void setScrollPosition (int x, int y)
	{
	// According to the JCL we throw a NullPointerException if there
	// is no child.
	if (ncomponents == 0)
	throw new NullPointerException ("no child in ScrollPane");

	Dimension child_d = component[0].getPreferredSize ();
	Dimension our_d = getViewportSize ();

	int xmax = Math.max (0, child_d.width - our_d.width);
	int ymax = Math.max (0, child_d.height - our_d.height);

	if (x < 0)
	x = 0;
	else if (x > xmax)
	x = xmax;
	if (y < 0)
	y = 0;
	else if (y > ymax)
	y = ymax;

	ScrollPanePeer spp = (ScrollPanePeer) peer;
	spp.setScrollPosition (x, y);
	}

	/** Sets the scroll position for this ScrollPane. If the point if
	* out of range it is silently moved within range.
	* @param p The new point
	*/
	public void setScrollPosition (Point p)
	{
	setScrollPosition (p.x, p.y);
	}

	// This implements the Adjustable for each scrollbar. The
	// expectation is that the peer will look at these objects directly
	// and modify the values in them when the user manipulates the
	// scrollbars. This has to be done from CNI to bypass Java
	// protection rules. The peer should also take care of calling the
	// adjustment listeners.
	class ScrollPaneAdjustable implements Adjustable
	{
	AdjustmentListener listeners;
	int orient;
	int unit;
	int block;
	int value;

	public ScrollPaneAdjustable (int orient)
	{
	this.orient = orient;
	}

	public void addAdjustmentListener (AdjustmentListener l)
	{
	listeners = AWTEventMulticaster.add (listeners, l);
	}

	public int getBlockIncrement ()
	{
	return block;
	}

	public int getMaximum ()
	{
	Dimension child_d = component[0].getPreferredSize ();
	Dimension our_d = getViewportSize ();

	int xmax = Math.max (0, child_d.width - our_d.width);
	int ymax = Math.max (0, child_d.height - our_d.height);

	return (orient == Adjustable.HORIZONTAL) ? xmax : ymax;
	}

	public int getMinimum ()
	{
	return 0;
	}

	public int getOrientation ()
	{
	return orient;
	}

	public int getUnitIncrement ()
	{
	return unit;
	}

	public int getValue ()
	{
	return value;
	}

	public int getVisibleAmount ()
	{
	Dimension d = getViewportSize ();
	return (orient == Adjustable.HORIZONTAL) ? d.width : d.height;
	}

	public void removeAdjustmentListener (AdjustmentListener l)
	{
	listeners = AWTEventMulticaster.remove (listeners, l);
	}

	public void setBlockIncrement (int b)
	{
	throw new AWTError ("can't use setBlockIncrement on this Adjustable");
	}

	public void setMaximum (int max)
	{
	throw new AWTError ("can't use setMaximum on this Adjustable");
	}

	public void setMinimum (int min)
	{
	throw new AWTError ("can't use setMinimum on this Adjustable");
	}

	public void setUnitIncrement (int u)
	{
	unit = u;
	if (peer != null)
	{
	ScrollPanePeer spp = (ScrollPanePeer) peer;
	spp.setUnitIncrement (this, u);
	}
	}

	public void setValue (int v)
	{
	value = v;
	if (peer != null)
	{
	ScrollPanePeer spp = (ScrollPanePeer) peer;
	spp.setValue (this, v);
	}
	}

	public void setVisibleAmount (int v)
	{
	throw new AWTError ("can't use setVisibleAmount on this Adjustable");
	}
	}

	ScrollPaneAdjustable hscroll
	= new ScrollPaneAdjustable (Adjustable.HORIZONTAL);
	ScrollPaneAdjustable vscroll
	= new ScrollPaneAdjustable (Adjustable.VERTICAL);
	int policy;
	}