/* BasicButtonUI.java --
Copyright (C) 2002, 2004, 2005 Free Software Foundation, Inc.
This file is part of GNU Classpath.
GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
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02110-1301 USA.
Linking this library statically or dynamically with other modules is
making a combined work based on this library. Thus, the terms and
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As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent
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package javax.swing.plaf.basic;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics;
import java.awt.Insets;
import java.awt.Rectangle;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import javax.swing.AbstractButton;
import javax.swing.ButtonModel;
import javax.swing.Icon;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.LookAndFeel;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;
import javax.swing.plaf.ButtonUI;
import javax.swing.plaf.ComponentUI;
import javax.swing.plaf.UIResource;
import javax.swing.text.View;
/**
* A UI delegate for the {@link JButton} component.
*/
public class BasicButtonUI extends ButtonUI
{
/**
* Cached rectangle for layouting the label. Used in paint() and
* BasicGraphicsUtils.getPreferredButtonSize().
*/
static Rectangle viewR = new Rectangle();
/**
* Cached rectangle for layouting the label. Used in paint() and
* BasicGraphicsUtils.getPreferredButtonSize().
*/
static Rectangle iconR = new Rectangle();
/**
* Cached rectangle for layouting the label. Used in paint() and
* BasicGraphicsUtils.getPreferredButtonSize().
*/
static Rectangle textR = new Rectangle();
/**
* Cached Insets instance, used in paint().
*/
static Insets cachedInsets;
/**
* The shared button UI.
*/
private static BasicButtonUI sharedUI;
/**
* The shared BasicButtonListener.
*/
private static BasicButtonListener sharedListener;
/**
* A constant used to pad out elements in the button's layout and
* preferred size calculations.
*/
protected int defaultTextIconGap = 4;
/**
* A constant added to the defaultTextIconGap to adjust the text
* within this particular button.
*/
protected int defaultTextShiftOffset;
private int textShiftOffset;
/**
* Factory method to create an instance of BasicButtonUI for a given
* {@link JComponent}, which should be an {@link AbstractButton}.
*
* @param c The component.
*
* @return A new UI capable of drawing the component
*/
public static ComponentUI createUI(final JComponent c)
{
if (sharedUI == null)
sharedUI = new BasicButtonUI();
return sharedUI;
}
/**
* Returns the default gap between the button's text and icon (in pixels).
*
* @param b the button (ignored).
*
* @return The gap.
*/
public int getDefaultTextIconGap(AbstractButton b)
{
return defaultTextIconGap;
}
/**
* Sets the text shift offset to zero.
*
* @see #setTextShiftOffset()
*/
protected void clearTextShiftOffset()
{
textShiftOffset = 0;
}
/**
* Returns the text shift offset.
*
* @return The text shift offset.
*
* @see #clearTextShiftOffset()
* @see #setTextShiftOffset()
*/
protected int getTextShiftOffset()
{
return textShiftOffset;
}
/**
* Sets the text shift offset to the value in {@link #defaultTextShiftOffset}.
*
* @see #clearTextShiftOffset()
*/
protected void setTextShiftOffset()
{
textShiftOffset = defaultTextShiftOffset;
}
/**
* Returns the prefix for the UI defaults property for this UI class.
* This is 'Button' for this class.
*
* @return the prefix for the UI defaults property
*/
protected String getPropertyPrefix()
{
return "Button.";
}
/**
* Installs the default settings.
*
* @param b the button (<code>null</code> not permitted).
*/
protected void installDefaults(AbstractButton b)
{
String prefix = getPropertyPrefix();
// Install colors and font.
LookAndFeel.installColorsAndFont(b, prefix + "background",
prefix + "foreground", prefix + "font");
// Install border.
LookAndFeel.installBorder(b, prefix + "border");
// Install margin property.
if (b.getMargin() == null || b.getMargin() instanceof UIResource)
b.setMargin(UIManager.getInsets(prefix + "margin"));
// Install rollover property.
Object rollover = UIManager.get(prefix + "rollover");
if (rollover != null)
LookAndFeel.installProperty(b, "rolloverEnabled", rollover);
// Fetch default textShiftOffset.
defaultTextShiftOffset = UIManager.getInt(prefix + "textShiftOffset");
// Make button opaque if needed.
if (b.isContentAreaFilled())
LookAndFeel.installProperty(b, "opaque", Boolean.TRUE);
else
LookAndFeel.installProperty(b, "opaque", Boolean.FALSE);
}
/**
* Removes the defaults added by {@link #installDefaults(AbstractButton)}.
*
* @param b the button (<code>null</code> not permitted).
*/
protected void uninstallDefaults(AbstractButton b)
{
// The other properties aren't uninstallable.
LookAndFeel.uninstallBorder(b);
}
/**
* Creates and returns a new instance of {@link BasicButtonListener}. This
* method provides a hook to make it easy for subclasses to install a
* different listener.
*
* @param b the button.
*
* @return A new listener.
*/
protected BasicButtonListener createButtonListener(AbstractButton b)
{
// Note: The RI always returns a new instance here. However,
// the BasicButtonListener class is perfectly suitable to be shared
// between multiple buttons, so we return a shared instance here
// for efficiency.
if (sharedListener == null)
sharedListener = new BasicButtonListener(b);
return sharedListener;
}
/**
* Installs listeners for the button.
*
* @param b the button (<code>null</code> not permitted).
*/
protected void installListeners(AbstractButton b)
{
BasicButtonListener listener = createButtonListener(b);
if (listener != null)
{
b.addChangeListener(listener);
b.addPropertyChangeListener(listener);
b.addFocusListener(listener);
b.addMouseListener(listener);
b.addMouseMotionListener(listener);
}
// Fire synthetic property change event to let the listener update
// the TextLayout cache.
listener.propertyChange(new PropertyChangeEvent(b, "font", null,
b.getFont()));
}
/**
* Uninstalls listeners for the button.
*
* @param b the button (<code>null</code> not permitted).
*/
protected void uninstallListeners(AbstractButton b)
{
BasicButtonListener listener = getButtonListener(b);
if (listener != null)
{
b.removeChangeListener(listener);
b.removePropertyChangeListener(listener);
b.removeFocusListener(listener);
b.removeMouseListener(listener);
b.removeMouseMotionListener(listener);
}
}
protected void installKeyboardActions(AbstractButton b)
{
BasicButtonListener listener = getButtonListener(b);
if (listener != null)
listener.installKeyboardActions(b);
}
protected void uninstallKeyboardActions(AbstractButton b)
{
BasicButtonListener listener = getButtonListener(b);
if (listener != null)
listener.uninstallKeyboardActions(b);
}
/**
* Install the BasicButtonUI as the UI for a particular component.
* This means registering all the UI's listeners with the component,
* and setting any properties of the button which are particular to
* this look and feel.
*
* @param c The component to install the UI into
*/
public void installUI(final JComponent c)
{
super.installUI(c);
if (c instanceof AbstractButton)
{
AbstractButton b = (AbstractButton) c;
installDefaults(b);
// It is important to install the listeners before installing
// the keyboard actions, because the keyboard actions
// are actually installed on the listener instance.
installListeners(b);
installKeyboardActions(b);
BasicHTML.updateRenderer(b, b.getText());
}
}
/**
* Uninstalls the UI from the component.
*
* @param c the component from which to uninstall the UI
*/
public void uninstallUI(JComponent c)
{
if (c instanceof AbstractButton)
{
AbstractButton b = (AbstractButton) c;
uninstallKeyboardActions(b);
uninstallListeners(b);
uninstallDefaults(b);
BasicHTML.updateRenderer(b, "");
b.putClientProperty(BasicGraphicsUtils.CACHED_TEXT_LAYOUT, null);
}
}
/**
* Calculates the minimum size for the specified component.
*
* @param c the component for which to compute the minimum size
*
* @return the minimum size for the specified component
*/
public Dimension getMinimumSize(JComponent c)
{
Dimension size = getPreferredSize(c);
// When the HTML view has a minimum width different from the preferred
// width, then substract this here accordingly. The height is not
// affected by that.
View html = (View) c.getClientProperty(BasicHTML.propertyKey);
if (html != null)
{
size.width -= html.getPreferredSpan(View.X_AXIS)
- html.getPreferredSpan(View.X_AXIS);
}
return size;
}
/**
* Calculates the maximum size for the specified component.
*
* @param c the component for which to compute the maximum size
*
* @return the maximum size for the specified component
*/
public Dimension getMaximumSize(JComponent c)
{
Dimension size = getPreferredSize(c);
// When the HTML view has a maximum width different from the preferred
// width, then add this here accordingly. The height is not
// affected by that.
View html = (View) c.getClientProperty(BasicHTML.propertyKey);
if (html != null)
{
size.width += html.getMaximumSpan(View.X_AXIS)
- html.getPreferredSpan(View.X_AXIS);
}
return size;
}
/**
* Calculate the preferred size of this component, by delegating to
* {@link BasicGraphicsUtils#getPreferredButtonSize}.
*
* @param c The component to measure
*
* @return The preferred dimensions of the component
*/
public Dimension getPreferredSize(JComponent c)
{
AbstractButton b = (AbstractButton) c;
Dimension d = BasicGraphicsUtils.getPreferredButtonSize(b,
b.getIconTextGap());
return d;
}
static Icon currentIcon(AbstractButton b)
{
Icon i = b.getIcon();
ButtonModel model = b.getModel();
if (model.isPressed() && b.getPressedIcon() != null && b.isEnabled())
i = b.getPressedIcon();
else if (model.isRollover())
{
if (b.isSelected() && b.getRolloverSelectedIcon() != null)
i = b.getRolloverSelectedIcon();
else if (b.getRolloverIcon() != null)
i = b.getRolloverIcon();
}
else if (b.isSelected() && b.isEnabled())
{
if (b.isEnabled() && b.getSelectedIcon() != null)
i = b.getSelectedIcon();
else if (b.getDisabledSelectedIcon() != null)
i = b.getDisabledSelectedIcon();
}
else if (! b.isEnabled() && b.getDisabledIcon() != null)
i = b.getDisabledIcon();
return i;
}
/**
* Paint the component, which is an {@link AbstractButton}, according to
* its current state.
*
* @param g The graphics context to paint with
* @param c The component to paint the state of
*/
public void paint(Graphics g, JComponent c)
{
AbstractButton b = (AbstractButton) c;
Insets i = c.getInsets(cachedInsets);
viewR.x = i.left;
viewR.y = i.top;
viewR.width = c.getWidth() - i.left - i.right;
viewR.height = c.getHeight() - i.top - i.bottom;
textR.x = 0;
textR.y = 0;
textR.width = 0;
textR.height = 0;
iconR.x = 0;
iconR.y = 0;
iconR.width = 0;
iconR.height = 0;
Font f = c.getFont();
g.setFont(f);
Icon icon = b.getIcon();
String text = b.getText();
text = SwingUtilities.layoutCompoundLabel(c, g.getFontMetrics(f),
text, icon,
b.getVerticalAlignment(),
b.getHorizontalAlignment(),
b.getVerticalTextPosition(),
b.getHorizontalTextPosition(),
viewR, iconR, textR,
text == null ? 0
: b.getIconTextGap());
ButtonModel model = b.getModel();
if (model.isArmed() && model.isPressed())
paintButtonPressed(g, b);
if (icon != null)
paintIcon(g, c, iconR);
if (text != null)
{
View html = (View) b.getClientProperty(BasicHTML.propertyKey);
if (html != null)
html.paint(g, textR);
else
paintText(g, b, textR, text);
}
if (b.isFocusOwner() && b.isFocusPainted())
paintFocus(g, b, viewR, textR, iconR);
}
/**
* Paint any focus decoration this {@link JComponent} might have. The
* component, which in this case will be an {@link AbstractButton},
* should only have focus decoration painted if it has the focus, and its
* "focusPainted" property is <code>true</code>.
*
* @param g Graphics context to paint with
* @param b Button to paint the focus of
* @param vr Visible rectangle, the area in which to paint
* @param tr Text rectangle, contained in visible rectangle
* @param ir Icon rectangle, contained in visible rectangle
*
* @see AbstractButton#isFocusPainted()
* @see JComponent#hasFocus()
*/
protected void paintFocus(Graphics g, AbstractButton b, Rectangle vr,
Rectangle tr, Rectangle ir)
{
// In the BasicLookAndFeel no focus border is drawn. This can be
// overridden in subclasses to implement such behaviour.
}
/**
* Paint the icon for this component. Depending on the state of the
* component and the availability of the button's various icon
* properties, this might mean painting one of several different icons.
*
* @param g Graphics context to paint with
* @param c Component to paint the icon of
* @param iconRect Rectangle in which the icon should be painted
*/
protected void paintIcon(Graphics g, JComponent c, Rectangle iconRect)
{
AbstractButton b = (AbstractButton) c;
Icon i = currentIcon(b);
if (i != null)
{
ButtonModel m = b.getModel();
if (m.isPressed() && m.isArmed())
{
int offs = getTextShiftOffset();
i.paintIcon(c, g, iconRect.x + offs, iconRect.y + offs);
}
else
i.paintIcon(c, g, iconRect.x, iconRect.y);
}
}
/**
* Paints the background area of an {@link AbstractButton} in the pressed
* state. This means filling the supplied area with a darker than normal
* background.
*
* @param g The graphics context to paint with
* @param b The button to paint the state of
*/
protected void paintButtonPressed(Graphics g, AbstractButton b)
{
if (b.isContentAreaFilled() && b.isOpaque())
{
Rectangle area = new Rectangle();
SwingUtilities.calculateInnerArea(b, area);
g.setColor(UIManager.getColor(getPropertyPrefix() + "shadow"));
g.fillRect(area.x, area.y, area.width, area.height);
}
}
/**
* Paints the "text" property of an {@link AbstractButton}.
*
* @param g The graphics context to paint with
* @param c The component to paint the state of
* @param textRect The area in which to paint the text
* @param text The text to paint
*/
protected void paintText(Graphics g, JComponent c, Rectangle textRect,
String text)
{
AbstractButton b = (AbstractButton) c;
Font f = b.getFont();
g.setFont(f);
FontMetrics fm = g.getFontMetrics(f);
if (b.isEnabled())
{
g.setColor(b.getForeground());
// FIXME: Underline mnemonic.
BasicGraphicsUtils.drawString(b, g, text, -1, textRect.x,
textRect.y + fm.getAscent());
}
else
{
String prefix = getPropertyPrefix();
g.setColor(UIManager.getColor(prefix + "disabledText"));
// FIXME: Underline mnemonic.
BasicGraphicsUtils.drawString(b, g, text, -1, textRect.x,
textRect.y + fm.getAscent());
}
}
/**
* Paints the "text" property of an {@link AbstractButton}.
*
* @param g The graphics context to paint with
* @param b The button to paint the state of
* @param textRect The area in which to paint the text
* @param text The text to paint
*
* @since 1.4
*/
protected void paintText(Graphics g, AbstractButton b, Rectangle textRect,
String text)
{
paintText(g, (JComponent) b, textRect, text);
}
/**
* A helper method that finds the BasicButtonListener for the specified
* button. This is there because this UI class is stateless and
* shared for all buttons, and thus can't store the listener
* as instance field. (We store our shared instance in sharedListener,
* however, subclasses may override createButtonListener() and we would
* be lost in this case).
*
* @param b the button
*
* @return the UI event listener
*/
private BasicButtonListener getButtonListener(AbstractButton b)
{
// The listener gets installed as PropertyChangeListener,
// so look for it in the list of property change listeners.
PropertyChangeListener[] listeners = b.getPropertyChangeListeners();
BasicButtonListener l = null;
for (int i = 0; listeners != null && l == null && i < listeners.length;
i++)
{
if (listeners[i] instanceof BasicButtonListener)
l = (BasicButtonListener) listeners[i];
}
return l;
}
}