JDK8/Java8源码在线阅读
/*
* Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* 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.
*/
package javax.swing.tree;
import java.awt.Color;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Insets;
import java.awt.Rectangle;
import javax.swing.plaf.ColorUIResource;
import javax.swing.plaf.FontUIResource;
import javax.swing.plaf.UIResource;
import javax.swing.plaf.basic.BasicGraphicsUtils;
import javax.swing.Icon;
import javax.swing.JLabel;
import javax.swing.JTree;
import javax.swing.LookAndFeel;
import javax.swing.UIManager;
import javax.swing.border.EmptyBorder;
import sun.swing.DefaultLookup;
/**
* Displays an entry in a tree.
* <code>DefaultTreeCellRenderer</code> is not opaque and
* unless you subclass paint you should not change this.
* See <a
href="https://docs.oracle.com/javase/tutorial/uiswing/components/tree.html">How to Use Trees</a>
* in <em>The Java Tutorial</em>
* for examples of customizing node display using this class.
* <p>
* The set of icons and colors used by {@code DefaultTreeCellRenderer}
* can be configured using the various setter methods. The value for
* each property is initialized from the defaults table. When the
* look and feel changes ({@code updateUI} is invoked), any properties
* that have a value of type {@code UIResource} are refreshed from the
* defaults table. The following table lists the mapping between
* {@code DefaultTreeCellRenderer} property and defaults table key:
* <table border="1" cellpadding="1" cellspacing="0" summary="">
* <tr valign="top" align="left">
* <th style="background-color:#CCCCFF" align="left">Property:
* <th style="background-color:#CCCCFF" align="left">Key:
* <tr><td>"leafIcon"<td>"Tree.leafIcon"
* <tr><td>"closedIcon"<td>"Tree.closedIcon"
* <tr><td>"openIcon"<td>"Tree.openIcon"
* <tr><td>"textSelectionColor"<td>"Tree.selectionForeground"
* <tr><td>"textNonSelectionColor"<td>"Tree.textForeground"
* <tr><td>"backgroundSelectionColor"<td>"Tree.selectionBackground"
* <tr><td>"backgroundNonSelectionColor"<td>"Tree.textBackground"
* <tr><td>"borderSelectionColor"<td>"Tree.selectionBorderColor"
* </table>
* <p>
* <strong><a name="override">Implementation Note:</a></strong>
* This class overrides
* <code>invalidate</code>,
* <code>validate</code>,
* <code>revalidate</code>,
* <code>repaint</code>,
* and
* <code>firePropertyChange</code>
* solely to improve performance.
* If not overridden, these frequently called methods would execute code paths
* that are unnecessary for the default tree cell renderer.
* If you write your own renderer,
* take care to weigh the benefits and
* drawbacks of overriding these methods.
*
* <p>
* <strong>Warning:</strong>
* 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 JavaBeans™
* has been added to the <code>java.beans</code> package.
* Please see {@link java.beans.XMLEncoder}.
*
* @author Rob Davis
* @author Ray Ryan
* @author Scott Violet
*/
public class DefaultTreeCellRenderer extends JLabel implements TreeCellRenderer
{
/** Last tree the renderer was painted in. */
private JTree tree;
/** Is the value currently selected. */
protected boolean selected;
/** True if has focus. */
protected boolean hasFocus;
/** True if draws focus border around icon as well. */
private boolean drawsFocusBorderAroundIcon;
/** If true, a dashed line is drawn as the focus indicator. */
private boolean drawDashedFocusIndicator;
// If drawDashedFocusIndicator is true, the following are used.
/**
* Background color of the tree.
*/
private Color treeBGColor;
/**
* Color to draw the focus indicator in, determined from the background.
* color.
*/
private Color focusBGColor;
// Icons
/** Icon used to show non-leaf nodes that aren't expanded. */
transient protected Icon closedIcon;
/** Icon used to show leaf nodes. */
transient protected Icon leafIcon;
/** Icon used to show non-leaf nodes that are expanded. */
transient protected Icon openIcon;
// Colors
/** Color to use for the foreground for selected nodes. */
protected Color textSelectionColor;
/** Color to use for the foreground for non-selected nodes. */
protected Color textNonSelectionColor;
/** Color to use for the background when a node is selected. */
protected Color backgroundSelectionColor;
/** Color to use for the background when the node isn't selected. */
protected Color backgroundNonSelectionColor;
/** Color to use for the focus indicator when the node has focus. */
protected Color borderSelectionColor;
private boolean isDropCell;
private boolean fillBackground;
/**
* Set to true after the constructor has run.
*/
private boolean inited;
/**
* Creates a {@code DefaultTreeCellRenderer}. Icons and text color are
* determined from the {@code UIManager}.
*/
public DefaultTreeCellRenderer() {
inited = true;
}
/**
* {@inheritDoc}
*
* @since 1.7
*/
public void updateUI() {
super.updateUI();
// To avoid invoking new methods from the constructor, the
// inited field is first checked. If inited is false, the constructor
// has not run and there is no point in checking the value. As
// all look and feels have a non-null value for these properties,
// a null value means the developer has specifically set it to
// null. As such, if the value is null, this does not reset the
// value.
if (!inited || (getLeafIcon() instanceof UIResource)) {
setLeafIcon(DefaultLookup.getIcon(this, ui, "Tree.leafIcon"));
}
if (!inited || (getClosedIcon() instanceof UIResource)) {
setClosedIcon(DefaultLookup.getIcon(this, ui, "Tree.closedIcon"));
}
if (!inited || (getOpenIcon() instanceof UIManager)) {
setOpenIcon(DefaultLookup.getIcon(this, ui, "Tree.openIcon"));
}
if (!inited || (getTextSelectionColor() instanceof UIResource)) {
setTextSelectionColor(
DefaultLookup.getColor(this, ui, "Tree.selectionForeground"));
}
if (!inited || (getTextNonSelectionColor() instanceof UIResource)) {
setTextNonSelectionColor(
DefaultLookup.getColor(this, ui, "Tree.textForeground"));
}
if (!inited || (getBackgroundSelectionColor() instanceof UIResource)) {
setBackgroundSelectionColor(
DefaultLookup.getColor(this, ui, "Tree.selectionBackground"));
}
if (!inited ||
(getBackgroundNonSelectionColor() instanceof UIResource)) {
setBackgroundNonSelectionColor(
DefaultLookup.getColor(this, ui, "Tree.textBackground"));
}
if (!inited || (getBorderSelectionColor() instanceof UIResource)) {
setBorderSelectionColor(
DefaultLookup.getColor(this, ui, "Tree.selectionBorderColor"));
}
drawsFocusBorderAroundIcon = DefaultLookup.getBoolean(
this, ui, "Tree.drawsFocusBorderAroundIcon", false);
drawDashedFocusIndicator = DefaultLookup.getBoolean(
this, ui, "Tree.drawDashedFocusIndicator", false);
fillBackground = DefaultLookup.getBoolean(this, ui, "Tree.rendererFillBackground", true);
Insets margins = DefaultLookup.getInsets(this, ui, "Tree.rendererMargins");
if (margins != null) {
setBorder(new EmptyBorder(margins.top, margins.left,
margins.bottom, margins.right));
}
setName("Tree.cellRenderer");
}
/**
* Returns the default icon, for the current laf, that is used to
* represent non-leaf nodes that are expanded.
*/
public Icon getDefaultOpenIcon() {
return DefaultLookup.getIcon(this, ui, "Tree.openIcon");
}
/**
* Returns the default icon, for the current laf, that is used to
* represent non-leaf nodes that are not expanded.
*/
public Icon getDefaultClosedIcon() {
return DefaultLookup.getIcon(this, ui, "Tree.closedIcon");
}
/**
* Returns the default icon, for the current laf, that is used to
* represent leaf nodes.
*/
public Icon getDefaultLeafIcon() {
return DefaultLookup.getIcon(this, ui, "Tree.leafIcon");
}
/**
* Sets the icon used to represent non-leaf nodes that are expanded.
*/
public void setOpenIcon(Icon newIcon) {
openIcon = newIcon;
}
/**
* Returns the icon used to represent non-leaf nodes that are expanded.
*/
public Icon getOpenIcon() {
return openIcon;
}
/**
* Sets the icon used to represent non-leaf nodes that are not expanded.
*/
public void setClosedIcon(Icon newIcon) {
closedIcon = newIcon;
}
/**
* Returns the icon used to represent non-leaf nodes that are not
* expanded.
*/
public Icon getClosedIcon() {
return closedIcon;
}
/**
* Sets the icon used to represent leaf nodes.
*/
public void setLeafIcon(Icon newIcon) {
leafIcon = newIcon;
}
/**
* Returns the icon used to represent leaf nodes.
*/
public Icon getLeafIcon() {
return leafIcon;
}
/**
* Sets the color the text is drawn with when the node is selected.
*/
public void setTextSelectionColor(Color newColor) {
textSelectionColor = newColor;
}
/**
* Returns the color the text is drawn with when the node is selected.
*/
public Color getTextSelectionColor() {
return textSelectionColor;
}
/**
* Sets the color the text is drawn with when the node isn't selected.
*/
public void setTextNonSelectionColor(Color newColor) {
textNonSelectionColor = newColor;
}
/**
* Returns the color the text is drawn with when the node isn't selected.
*/
public Color getTextNonSelectionColor() {
return textNonSelectionColor;
}
/**
* Sets the color to use for the background if node is selected.
*/
public void setBackgroundSelectionColor(Color newColor) {
backgroundSelectionColor = newColor;
}
/**
* Returns the color to use for the background if node is selected.
*/
public Color getBackgroundSelectionColor() {
return backgroundSelectionColor;
}
/**
* Sets the background color to be used for non selected nodes.
*/
public void setBackgroundNonSelectionColor(Color newColor) {
backgroundNonSelectionColor = newColor;
}
/**
* Returns the background color to be used for non selected nodes.
*/
public Color getBackgroundNonSelectionColor() {
return backgroundNonSelectionColor;
}
/**
* Sets the color to use for the border.
*/
public void setBorderSelectionColor(Color newColor) {
borderSelectionColor = newColor;
}
/**
* Returns the color the border is drawn.
*/
public Color getBorderSelectionColor() {
return borderSelectionColor;
}
/**
* Subclassed to map <code>FontUIResource</code>s to null. If
* <code>font</code> is null, or a <code>FontUIResource</code>, this
* has the effect of letting the font of the JTree show
* through. On the other hand, if <code>font</code> is non-null, and not
* a <code>FontUIResource</code>, the font becomes <code>font</code>.
*/
public void setFont(Font font) {
if(font instanceof FontUIResource)
font = null;
super.setFont(font);
}
/**
* Gets the font of this component.
* @return this component's font; if a font has not been set
* for this component, the font of its parent is returned
*/
public Font getFont() {
Font font = super.getFont();
if (font == null && tree != null) {
// Strive to return a non-null value, otherwise the html support
// will typically pick up the wrong font in certain situations.
font = tree.getFont();
}
return font;
}
/**
* Subclassed to map <code>ColorUIResource</code>s to null. If
* <code>color</code> is null, or a <code>ColorUIResource</code>, this
* has the effect of letting the background color of the JTree show
* through. On the other hand, if <code>color</code> is non-null, and not
* a <code>ColorUIResource</code>, the background becomes
* <code>color</code>.
*/
public void setBackground(Color color) {
if(color instanceof ColorUIResource)
color = null;
super.setBackground(color);
}
/**
* Configures the renderer based on the passed in components.
* The value is set from messaging the tree with
* <code>convertValueToText</code>, which ultimately invokes
* <code>toString</code> on <code>value</code>.
* The foreground color is set based on the selection and the icon
* is set based on the <code>leaf</code> and <code>expanded</code>
* parameters.
*/
public Component getTreeCellRendererComponent(JTree tree, Object value,
boolean sel,
boolean expanded,
boolean leaf, int row,
boolean hasFocus) {
String stringValue = tree.convertValueToText(value, sel,
expanded, leaf, row, hasFocus);
this.tree = tree;
this.hasFocus = hasFocus;
setText(stringValue);
Color fg = null;
isDropCell = false;
JTree.DropLocation dropLocation = tree.getDropLocation();
if (dropLocation != null
&& dropLocation.getChildIndex() == -1
&& tree.getRowForPath(dropLocation.getPath()) == row) {
Color col = DefaultLookup.getColor(this, ui, "Tree.dropCellForeground");
if (col != null) {
fg = col;
} else {
fg = getTextSelectionColor();
}
isDropCell = true;
} else if (sel) {
fg = getTextSelectionColor();
} else {
fg = getTextNonSelectionColor();
}
setForeground(fg);
Icon icon = null;
if (leaf) {
icon = getLeafIcon();
} else if (expanded) {
icon = getOpenIcon();
} else {
icon = getClosedIcon();
}
if (!tree.isEnabled()) {
setEnabled(false);
LookAndFeel laf = UIManager.getLookAndFeel();
Icon disabledIcon = laf.getDisabledIcon(tree, icon);
if (disabledIcon != null) icon = disabledIcon;
setDisabledIcon(icon);
} else {
setEnabled(true);
setIcon(icon);
}
setComponentOrientation(tree.getComponentOrientation());
selected = sel;
return this;
}
/**
* Paints the value. The background is filled based on selected.
*/
public void paint(Graphics g) {
Color bColor;
if (isDropCell) {
bColor = DefaultLookup.getColor(this, ui, "Tree.dropCellBackground");
if (bColor == null) {
bColor = getBackgroundSelectionColor();
}
} else if (selected) {
bColor = getBackgroundSelectionColor();
} else {
bColor = getBackgroundNonSelectionColor();
if (bColor == null) {
bColor = getBackground();
}
}
int imageOffset = -1;
if (bColor != null && fillBackground) {
imageOffset = getLabelStart();
g.setColor(bColor);
if(getComponentOrientation().isLeftToRight()) {
g.fillRect(imageOffset, 0, getWidth() - imageOffset,
getHeight());
} else {
g.fillRect(0, 0, getWidth() - imageOffset,
getHeight());
}
}
if (hasFocus) {
if (drawsFocusBorderAroundIcon) {
imageOffset = 0;
}
else if (imageOffset == -1) {
imageOffset = getLabelStart();
}
if(getComponentOrientation().isLeftToRight()) {
paintFocus(g, imageOffset, 0, getWidth() - imageOffset,
getHeight(), bColor);
} else {
paintFocus(g, 0, 0, getWidth() - imageOffset, getHeight(), bColor);
}
}
super.paint(g);
}
private void paintFocus(Graphics g, int x, int y, int w, int h, Color notColor) {
Color bsColor = getBorderSelectionColor();
if (bsColor != null && (selected || !drawDashedFocusIndicator)) {
g.setColor(bsColor);
g.drawRect(x, y, w - 1, h - 1);
}
if (drawDashedFocusIndicator && notColor != null) {
if (treeBGColor != notColor) {
treeBGColor = notColor;
focusBGColor = new Color(~notColor.getRGB());
}
g.setColor(focusBGColor);
BasicGraphicsUtils.drawDashedRect(g, x, y, w, h);
}
}
private int getLabelStart() {
Icon currentI = getIcon();
if(currentI != null && getText() != null) {
return currentI.getIconWidth() + Math.max(0, getIconTextGap() - 1);
}
return 0;
}
/**
* Overrides <code>JComponent.getPreferredSize</code> to
* return slightly wider preferred size value.
*/
public Dimension getPreferredSize() {
Dimension retDimension = super.getPreferredSize();
if(retDimension != null)
retDimension = new Dimension(retDimension.width + 3,
retDimension.height);
return retDimension;
}
/**
* Overridden for performance reasons.
* See the <a href="#override">Implementation Note</a>
* for more information.
*/
public void validate() {}
/**
* Overridden for performance reasons.
* See the <a href="#override">Implementation Note</a>
* for more information.
*
* @since 1.5
*/
public void invalidate() {}
/**
* Overridden for performance reasons.
* See the <a href="#override">Implementation Note</a>
* for more information.
*/
public void revalidate() {}
/**
* Overridden for performance reasons.
* See the <a href="#override">Implementation Note</a>
* for more information.
*/
public void repaint(long tm, int x, int y, int width, int height) {}
/**
* Overridden for performance reasons.
* See the <a href="#override">Implementation Note</a>
* for more information.
*/
public void repaint(Rectangle r) {}
/**
* Overridden for performance reasons.
* See the <a href="#override">Implementation Note</a>
* for more information.
*
* @since 1.5
*/
public void repaint() {}
/**
* Overridden for performance reasons.
* See the <a href="#override">Implementation Note</a>
* for more information.
*/
/**代码未完, 请加载全部代码(NowJava.com).**/
关注时代Java
关注时代Java