I have essentially rewritten most of JLayeredPane. I noticed some
troubles with this class and read a little in the OReilly Swing book 1st
edition. I learned that we did a couple of things wrong in this class:
- we stored all components and their layers in the Hashtable. This is
wrong. JComponents should have their layer stored as client property
with LAYER_PROPERTY as key.
- a lot of the methods used to throw IllegalArgumentExceptions for
unusual arguments like components that are not children of the layered
pane. These methods should ignore this instead and return -1 or 0. (This
error actually caused several problems in some applications)
Also, our implementation used a second datastructure called 'layers' to
manage the layers. This is really not needed and makes maintainence of
the code less straightforward. I removed this and rewrote most stuff in
a more straightforward manner.
2006-01-27 Roman Kennke <[EMAIL PROTECTED]>
* javax/swing/JLayeredPane.java
(FRAME_CONTENT_LAYER): Made field final.
(componentToLayer): Made field private.
(rectCache): Removed field.
(layers): Removed field.
(JLayeredPane()): Removed initialization of removed fields.
(getLayer): Rewritten to make use of client properties in
JComponents and to be more straighforward.
(static getLayer): Rewritten to make use of client properties in
JComponents.
(layerToRange): Removed method.
(incrLayer): Removed method.
(decrLayer): Removed method.
(highestLayer): Rewritten to be more straightforward.
(lowestLayer): Rewritten to be more straightforward.
(getPosition): Rewritten to be more straightforward.
(getComponentsInLayer): Rewritten to be more straightforward.
(getComponentCountInLayer): Rewritten to be more straightforward.
(getIndexOf): Rewritten to be more straightforward.
(inserIndexForLayer): Rewritten to be more straightforward.
(remove): Rewritten to be more straightforward.
(setLayer): Rewritten to be more straightforward.
(addImpl): Rewritten to be more straightforward.
(putLayer): Rewritten to be more straightforward.
/Roman
Index: javax/swing/JLayeredPane.java
===================================================================
RCS file: /cvsroot/classpath/classpath/javax/swing/JLayeredPane.java,v
retrieving revision 1.37
diff -u -r1.37 JLayeredPane.java
--- javax/swing/JLayeredPane.java 27 Jan 2006 15:51:21 -0000 1.37
+++ javax/swing/JLayeredPane.java 27 Jan 2006 19:56:19 -0000
@@ -43,11 +43,7 @@
import java.awt.Container;
import java.awt.Graphics;
import java.awt.Rectangle;
-import java.awt.Shape;
import java.util.Hashtable;
-import java.util.Iterator;
-import java.util.Map;
-import java.util.TreeMap;
import javax.accessibility.Accessible;
import javax.accessibility.AccessibleContext;
@@ -119,6 +115,7 @@
* component indexing and position order</p>
*
* @author Graydon Hoare ([EMAIL PROTECTED])
+ * @author Roman Kennke ([EMAIL PROTECTED])
*/
public class JLayeredPane extends JComponent implements Accessible
{
@@ -150,7 +147,7 @@
public static final String LAYER_PROPERTY = "layeredContainerLayer";
- public static Integer FRAME_CONTENT_LAYER = new Integer (-30000);
+ public static final Integer FRAME_CONTENT_LAYER = new Integer (-30000);
public static final Integer DEFAULT_LAYER = new Integer (0);
public static final Integer PALETTE_LAYER = new Integer (100);
@@ -158,14 +155,10 @@
public static final Integer POPUP_LAYER = new Integer (300);
public static final Integer DRAG_LAYER = new Integer (400);
- TreeMap layers; // Layer Number (Integer) -> Layer Size (Integer)
- Hashtable componentToLayer; // Component -> Layer Number (Integer)
+ private Hashtable componentToLayer; // Component -> Layer Number (Integer)
- private transient Rectangle rectCache;
-
public JLayeredPane()
{
- layers = new TreeMap ();
componentToLayer = new Hashtable ();
setLayout(null);
}
@@ -173,47 +166,50 @@
/**
* Looks up the layer a child component is currently assigned to.
*
+ * If <code>c</code> is an instance of [EMAIL PROTECTED] JComponent}, then the layer
+ * is fetched from the client property with the key [EMAIL PROTECTED] #LAYER_PROPERTY}.
+ * Otherwise it is looked up in an internal hashtable that maps
+ * non-JComponent components to layers. If the components cannot be found
+ * in either way, the [EMAIL PROTECTED] #DEFAULT_LAYER} is returned.
+ *
* @param c the component to look up.
- * @return the layer the component is currently assigned to, in this container.
- * @throws IllegalArgumentException if the component is not a child of this container.
+ *
+ * @return the layer the component is currently assigned to; if the component
+ * is not in this layered pane, then 0 (DEFAULT_LAYER) is returned
*/
public int getLayer(Component c)
{
- Component myComp = c;
- while(! componentToLayer.containsKey(myComp))
+ Integer layerObj;
+ if (c instanceof JComponent)
{
- myComp = myComp.getParent();
- if (myComp == null)
- break;
+ JComponent jc = (JComponent) c;
+ layerObj = (Integer) jc.getClientProperty(LAYER_PROPERTY);
}
- if (myComp == null)
- throw new IllegalArgumentException
- ("component is not in this JLayeredPane");
- Integer layerObj = (Integer) componentToLayer.get(myComp);
+ else
+ layerObj = (Integer) componentToLayer.get(c);
+
+ if (layerObj == null)
+ layerObj = DEFAULT_LAYER;
+
return layerObj.intValue();
}
/**
- * Looks up the layer of <code>comp</code> in the component's nearest
- * JLayeredPane ancestor. If <code>comp</code> is not contained
- * in a JLayeredPane, the value 0 (default layer) is returned.
- *
+ * Looks up the layer in the client property with the key
+ * [EMAIL PROTECTED] #LAYER_PROPERTY} of <code>comp</code>. If no such property can be
+ * found, we return <code>0</code> ([EMAIL PROTECTED] #DEFAULT_LAYER}).
+ *
* @param comp the component for which the layer is looked up
*
- * @return the layer of <code>comp</code> in its nearest JLayeredPane
- * ancestor
+ * @return the layer of <code>comp</code> as stored in the corresponding
+ * client property, or <code>0</code> if there is no such property
*/
public static int getLayer(JComponent comp)
{
- JLayeredPane lp = (JLayeredPane) SwingUtilities.getAncestorOfClass
- (JLayeredPane.class, comp);
- if (lp == null)
- return 0;
- else
- // The cast here forces the call to the instance method getLayer()
- // instead of the static method (this would lead to infinite
- // recursion).
- return lp.getLayer((Component) comp);
+ Integer layerObj = (Integer) comp.getClientProperty(LAYER_PROPERTY);
+ if (layerObj == null)
+ layerObj = DEFAULT_LAYER;
+ return layerObj.intValue();
}
/**
@@ -236,105 +232,49 @@
}
/**
- * <p>Returns a pair of ints representing a half-open interval
- * <code>[top, bottom)</code>, which is the range of component indices
- * the provided layer number corresponds to.</p>
- *
- * <p>Note that "bottom" is <em>not</em> included in the interval of
- * component indices in this layer: a layer with 0 elements in it has
- * <code>ret[0] == ret[1]</code>.</p>
- *
- * @param layer the layer to look up.
- * @return the half-open range of indices this layer spans.
- * @throws IllegalArgumentException if layer does not refer to an active layer
- * in this container.
- */
- private int[] layerToRange (Integer layer)
- {
- int[] ret = new int[2];
- ret[1] = getComponents ().length;
- Iterator i = layers.entrySet ().iterator ();
- while (i.hasNext())
- {
- Map.Entry pair = (Map.Entry) i.next();
- Integer layerNum = (Integer) pair.getKey ();
- Integer layerSz = (Integer) pair.getValue ();
- int layerInt = layerNum.intValue();
- if (layerInt == layer.intValue())
- {
- ret[0] = ret[1] - layerSz.intValue ();
- break;
- }
- // In the following case there exists no layer with the specified
- // number, so we return an empty interval here with the index at which
- // such a layer would be inserted
- else if (layerInt > layer.intValue())
- {
- ret[1] = ret[0];
- break;
- }
- else
- {
- ret[1] -= layerSz.intValue ();
- }
- }
- return ret;
- }
-
- /**
- * Increments the recorded size of a given layer.
- *
- * @param layer the layer number to increment.
- * @see #incrLayer
- */
- private void incrLayer(Integer layer)
- {
- int sz = 1;
- if (layers.containsKey (layer))
- sz += ((Integer)(layers.get (layer))).intValue ();
- layers.put (layer, new Integer(sz));
- }
-
- /**
- * Decrements the recorded size of a given layer.
- *
- * @param layer the layer number to decrement.
- * @see #incrLayer
- */
- private void decrLayer(Integer layer)
- {
- int sz = 0;
- if (layers.containsKey (layer))
- sz = ((Integer)(layers.get (layer))).intValue () - 1;
- layers.put (layer, new Integer(sz));
- }
-
- /**
* Return the greatest layer number currently in use, in this container.
* This number may legally be positive <em>or</em> negative.
*
- * @return the least layer number.
+ * @return the highest layer number
+ *
* @see #lowestLayer()
*/
public int highestLayer()
{
- if (layers.size() == 0)
- return 0;
- return ((Integer)(layers.lastKey ())).intValue ();
+ Component[] components = getComponents();
+ int highest;
+ if (components.length == 0)
+ highest = 0;
+ else
+ {
+ highest = Integer.MIN_VALUE;
+ for (int i = 0; i < components.length; i++)
+ highest = Math.max(highest, getLayer(components[i]));
+ }
+ return highest;
}
/**
* Return the least layer number currently in use, in this container.
* This number may legally be positive <em>or</em> negative.
*
- * @return the least layer number.
+ * @return the least layer number
+ *
* @see #highestLayer()
*/
public int lowestLayer()
{
- if (layers.size() == 0)
- return 0;
- return ((Integer)(layers.firstKey ())).intValue ();
+ Component[] components = getComponents();
+ int lowest;
+ if (components.length == 0)
+ lowest = 0;
+ else
+ {
+ lowest = Integer.MAX_VALUE;
+ for (int i = 0; i < components.length; i++)
+ lowest = Math.max(lowest, getLayer(components[i]));
+ }
+ return lowest;
}
/**
@@ -343,9 +283,8 @@
* layer, so is usually the component which occludes the most other
* components in its layer.
*
- * @param c the component to move to the front of its layer.
- * @throws IllegalArgumentException if the component is not a child of
- * this container.
+ * @param c the component to move to the front of its layer
+ *
* @see #moveToBack
*/
public void moveToFront(Component c)
@@ -363,8 +302,7 @@
* other components in its layer.</p>
*
* @param c the component to move to the back of its layer.
- * @throws IllegalArgumentException if the component is not a child of
- * this container.
+ *
* @see #moveToFront
*/
public void moveToBack(Component c)
@@ -377,25 +315,30 @@
* from the "front" (position 0) to the "back" (position N-1), and drawn from
* the back towards the front.
*
- * @param c the component to get the position of.
- * @throws IllegalArgumentException if the component is not a child of
- * this container.
+ * @param c the component to get the position of
+ *
+ * @return the position of <code>c</code> within its layer or -1 if
+ * <code>c</code> is not a child of this layered pane
+ *
* @see #setPosition
*/
public int getPosition(Component c)
{
- int layer = getLayer (c);
- int[] range = layerToRange(new Integer(layer));
- int top = range[0];
- int bot = range[1];
- Component[] comps = getComponents ();
- for (int i = top; i < bot; ++i)
- {
- if (comps[i] == c)
- return i - top;
- }
- // should have found it
- throw new IllegalArgumentException ();
+ int pos = -1;
+ int index = getIndexOf(c);
+ Component[] components = getComponents();
+ int layer = getLayer(c);
+ if (index >= 0)
+ {
+ for (int i = index; i >= 0; --i)
+ {
+ if (layer == getLayer(components[i]))
+ pos++;
+ else
+ break;
+ }
+ }
+ return pos;
}
/**
@@ -403,10 +346,9 @@
* from the "front" (position 0) to the "back" (position N-1), and drawn from
* the back towards the front.
*
- * @param c the component to change the position of.
- * @param position the position to assign the component to.
- * @throws IllegalArgumentException if the component is not a child of
- * this container.
+ * @param c the component to change the position of
+ * @param position the position to assign the component to
+ *
* @see #getPosition
*/
public void setPosition(Component c, int position)
@@ -428,39 +370,44 @@
* container. Components are ordered front-to-back, with the "front"
* element (which draws last) at position 0 of the returned array.
*
- * @param layer the layer to return components from.
- * @return the components in the layer.
+ * @param layer the layer to return components from
+ *
+ * @return the components in the layer
*/
public Component[] getComponentsInLayer(int layer)
{
- int[] range = layerToRange (getObjectForLayer (layer));
- if (range[0] == range[1])
- return new Component[0];
- else
- {
- Component[] comps = getComponents ();
- int sz = range[1] - range[0];
- Component[] nc = new Component[sz];
- for (int i = 0; i < sz; ++i)
- nc[i] = comps[range[0] + i];
- return nc;
- }
+ Component[] inLayer = new Component[getComponentCountInLayer(layer)];
+ Component[] components = getComponents();
+ int j = 0;
+ for (int i = 0; i < components.length; ++i)
+ {
+ if (layer == getLayer(components[i]))
+ {
+ inLayer[j] = components[i];
+ j++;
+ }
+ }
+ return inLayer;
}
/**
* Return the number of components within a layer of this
* container.
*
- * @param layer the layer count components in.
- * @return the number of components in the layer.
+ * @param layer the layer count components in
+ *
+ * @return the number of components in the layer
*/
public int getComponentCountInLayer(int layer)
{
- int[] range = layerToRange (getObjectForLayer (layer));
- if (range[0] == range[1])
- return 0;
- else
- return (range[1] - range[0]);
+ Component[] components = getComponents();
+ int count = 0;
+ for (int i = components.length - 1; i >= 0; --i)
+ {
+ if (getLayer(components[i]) == layer)
+ count++;
+ }
+ return count;
}
/**
@@ -479,23 +426,24 @@
* drawing order of all children of the container.
*
* @param c the component to look up.
- * @return the external index of the component.
- * @throws IllegalArgumentException if the component is not a child of
- * this container.
+ *
+ * @return the external index of the component or <code>-1</code> if
+ * <code>c</code> is not a child of this layered pane
*/
public int getIndexOf(Component c)
{
- int layer = getLayer (c);
- int[] range = layerToRange(new Integer(layer));
- Component[] comps = getComponents();
- for (int i = range[0]; i < range[1]; ++i)
- {
- if (comps[i] == c)
- return i;
- }
- // should have found the component during iteration
- throw new IllegalArgumentException ();
- }
+ int index = -1;
+ Component[] components = getComponents();
+ for (int i = 0; i < components.length; ++i)
+ {
+ if (components[i] == c)
+ {
+ index = i;
+ break;
+ }
+ }
+ return index;
+ }
/**
* Return an Integer object which holds the same int value as the
@@ -503,6 +451,7 @@
* identical Integer objects which we allocate.
*
* @param layer the layer number as an int.
+ *
* @return the layer number as an Integer, possibly shared.
*/
protected Integer getObjectForLayer(int layer)
@@ -541,25 +490,35 @@
*
* @param layer the layer in which to insert a component.
* @param position the position in the layer at which to insert a component.
+ *
* @return the index at which to insert the component.
*/
protected int insertIndexForLayer(int layer, int position)
{
+ Component[] components = getComponents();
+ int index = components.length;
- Integer lobj = getObjectForLayer (layer);
- if (! layers.containsKey(lobj))
- layers.put (lobj, new Integer (0));
- int[] range = layerToRange (lobj);
- if (range[0] == range[1])
- return range[0];
-
- int top = range[0];
- int bot = range[1];
-
- if (position == -1 || position > (bot - top))
- return bot;
- else
- return top + position;
+ // Try to find the start index of the specified layer.
+ int p = -1;
+ for (int i = components.length - 1; i >= 0; --i)
+ {
+ int l = getLayer(components[i]);
+ if (l > layer)
+ index = i;
+ // If we are in the layer we look for, try to find the position.
+ else if (l == layer)
+ {
+ p++;
+ if (p >= position)
+ index = i;
+ else
+ break;
+ }
+ // No need to look further if the layer at i is smaller than layer.
+ else
+ break;
+ }
+ return index;
}
/**
@@ -571,12 +530,9 @@
public void remove(int index)
{
Component c = getComponent(index);
- int layer = getLayer(c);
- decrLayer(new Integer(layer));
- componentToLayer.remove(c);
+ if (! (c instanceof JComponent))
+ componentToLayer.remove(c);
super.remove(index);
- // FIXME: Figure out if this call is correct.
- revalidate();
}
/**
@@ -592,7 +548,7 @@
*/
public void setLayer(Component c, int layer)
{
- componentToLayer.put (c, getObjectForLayer (layer));
+ setLayer(c, layer, -1);
}
/**
@@ -602,15 +558,20 @@
* @param layer the layer number to assign to the component.
* @param position the position number to assign to the component.
*/
- public void setLayer(Component c,
- int layer,
- int position)
- {
- remove(c);
- add(c, getObjectForLayer (layer));
- setPosition(c, position);
- revalidate();
- repaint();
+ public void setLayer(Component c, int layer, int position)
+ {
+ Integer layerObj = getObjectForLayer(layer);
+ if (c instanceof JComponent)
+ {
+ JComponent jc = (JComponent) c;
+ jc.putClientProperty(LAYER_PROPERTY, layerObj);
+ }
+ else
+ componentToLayer.put (c, layerObj);
+
+ // Set position only of component is already added to this layered pane.
+ if (getIndexOf(c) != -1)
+ setPosition(c, position);
}
/**
@@ -625,19 +586,14 @@
*/
protected void addImpl(Component comp, Object layerConstraint, int index)
{
- Integer layer;
+ int layer;
if (layerConstraint != null && layerConstraint instanceof Integer)
- layer = (Integer) layerConstraint;
- else if (componentToLayer.containsKey (comp))
- layer = (Integer) componentToLayer.remove (comp);
+ layer = ((Integer) layerConstraint).intValue();
else
- layer = DEFAULT_LAYER;
-
- int newIdx = insertIndexForLayer(layer.intValue (), index);
+ layer = getLayer(comp);
- componentToLayer.put (comp, layer);
- incrLayer (layer);
-
+ int newIdx = insertIndexForLayer(layer, index);
+ setLayer(comp, layer);
super.addImpl(comp, null, newIdx);
}
@@ -649,7 +605,7 @@
*/
public static void putLayer(JComponent component, int layer)
{
- getLayeredPaneAbove(component).setLayer(component, layer);
+ component.putClientProperty(LAYER_PROPERTY, new Integer(layer));
}
/**
@@ -743,7 +699,7 @@
remove(p2 + layerOffs);
remove(p1 + layerOffs);
// add() wants the position within the layer.
- Integer l = new Integer(layer);
+ Integer l = getObjectForLayer(layer);
add(c2, l, p1);
add(c1, l, p2);
}
