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/*
* 11/14/2003
*
* RTextScrollPane.java - A JScrollPane that will only accept RTextAreas
* so that it can display line numbers, fold indicators, and icons.
*
* This library is distributed under a modified BSD license. See the included
* RSyntaxTextArea.License.txt file for details.
*/
package org.fife.ui.rtextarea;
import java.awt.Color;
import java.awt.Component;
import java.awt.Container;
import java.awt.Font;
import java.util.Arrays;
import java.util.Stack;
import javax.swing.JScrollPane;
/**
* An extension of JScrollPane that will only take
* RTextAreas (or javax.swing.JLayers decorating
* RTextAreas) for its view. This class has the ability to show:
*
* - Line numbers
*
- Per-line icons (for bookmarks, debugging breakpoints, error markers, etc.)
*
- +/- icons to denote code folding regions.
*
*
* The actual "meat" of these extras is contained in the {@link Gutter} class.
* Each RTextScrollPane has a Gutter instance that
* it uses as its row header. The gutter is only made visible when one of its
* features is being used (line numbering, folding, and/or icons).
*
* @author Robert Futrell
* @version 1.0
*/
public class RTextScrollPane extends JScrollPane {
private Gutter gutter;
/**
* Constructor. If you use this constructor, you must call
* {@link #setViewportView(Component)} and pass in an {@link RTextArea}
* for this scroll pane to render line numbers properly.
*/
public RTextScrollPane() {
this(null, true);
}
/**
* Creates a scroll pane. A default value will be used for line number
* color (gray), and the current line's line number will be highlighted.
*
* @param comp The component this scroll pane should display. This should
* be an instance of {@link RTextArea},
* javax.swing.JLayer (or the older
* org.jdesktop.jxlayer.JXLayer), or null.
* If this argument is null, you must call
* {@link #setViewportView(Component)}, passing in an instance of
* one of the types above.
*/
public RTextScrollPane(Component comp) {
this(comp, true);
}
/**
* Creates a scroll pane. A default value will be used for line number
* color (gray), and the current line's line number will be highlighted.
*
* @param comp The component this scroll pane should display. This should
* be an instance of {@link RTextArea},
* javax.swing.JLayer (or the older
* org.jdesktop.jxlayer.JXLayer), or null.
* If this argument is null, you must call
* {@link #setViewportView(Component)}, passing in an instance of
* one of the types above.
* @param lineNumbers Whether line numbers should be enabled.
*/
public RTextScrollPane(Component comp, boolean lineNumbers) {
this(comp, lineNumbers, Color.GRAY);
}
/**
* Creates a scroll pane.
*
* @param comp The component this scroll pane should display. This should
* be an instance of {@link RTextArea},
* javax.swing.JLayer (or the older
* org.jdesktop.jxlayer.JXLayer), or null.
* If this argument is null, you must call
* {@link #setViewportView(Component)}, passing in an instance of
* one of the types above.
* @param lineNumbers Whether line numbers are initially enabled.
* @param lineNumberColor The color to use for line numbers.
*/
public RTextScrollPane(Component comp, boolean lineNumbers,
Color lineNumberColor) {
super(comp);
RTextArea textArea = getFirstRTextAreaDescendant(comp);
// Create the gutter for this document.
Font defaultFont = new Font("Monospaced", Font.PLAIN, 12);
gutter = new Gutter(textArea);
gutter.setLineNumberFont(defaultFont);
gutter.setLineNumberColor(lineNumberColor);
setLineNumbersEnabled(lineNumbers);
// Set miscellaneous properties.
setVerticalScrollBarPolicy(VERTICAL_SCROLLBAR_ALWAYS);
setHorizontalScrollBarPolicy(HORIZONTAL_SCROLLBAR_AS_NEEDED);
}
/**
* Ensures the gutter is visible if it's showing anything.
*/
private void checkGutterVisibility() {
int count = gutter.getComponentCount();
if (count==0) {
if (getRowHeader()!=null && getRowHeader().getView()==gutter) {
setRowHeaderView(null);
}
}
else {
if (getRowHeader()==null || getRowHeader().getView()==null) {
setRowHeaderView(gutter);
}
}
}
/**
* Returns the gutter.
*
* @return The gutter.
*/
public Gutter getGutter() {
return gutter;
}
/**
* Returns true if the line numbers are enabled and visible.
*
* @return Whether or not line numbers are visible.
* @see #setLineNumbersEnabled(boolean)
*/
public boolean getLineNumbersEnabled() {
return gutter.getLineNumbersEnabled();
}
/**
* Returns the text area being displayed.
*
* @return The text area.
* @see #setViewportView(Component)
*/
public RTextArea getTextArea() {
return (RTextArea)getViewport().getView();
}
/**
* Returns whether the fold indicator is enabled.
*
* @return Whether the fold indicator is enabled.
* @see #setFoldIndicatorEnabled(boolean)
*/
public boolean isFoldIndicatorEnabled() {
return gutter.isFoldIndicatorEnabled();
}
/**
* Returns whether the icon row header is enabled.
*
* @return Whether the icon row header is enabled.
* @see #setIconRowHeaderEnabled(boolean)
*/
public boolean isIconRowHeaderEnabled() {
return gutter.isIconRowHeaderEnabled();
}
/**
* Toggles whether the fold indicator is enabled.
*
* @param enabled Whether the fold indicator should be enabled.
* @see #isFoldIndicatorEnabled()
*/
public void setFoldIndicatorEnabled(boolean enabled) {
gutter.setFoldIndicatorEnabled(enabled);
checkGutterVisibility();
}
/**
* Toggles whether the icon row header (used for breakpoints, bookmarks,
* etc.) is enabled.
*
* @param enabled Whether the icon row header is enabled.
* @see #isIconRowHeaderEnabled()
*/
public void setIconRowHeaderEnabled(boolean enabled) {
gutter.setIconRowHeaderEnabled(enabled);
checkGutterVisibility();
}
/**
* Toggles whether or not line numbers are visible.
*
* @param enabled Whether or not line numbers should be visible.
* @see #getLineNumbersEnabled()
*/
public void setLineNumbersEnabled(boolean enabled) {
gutter.setLineNumbersEnabled(enabled);
checkGutterVisibility();
}
/**
* Sets the view for this scroll pane. This must be an {@link RTextArea}.
*
* @param view The new view.
* @see #getTextArea()
*/
@Override
public void setViewportView(Component view) {
RTextArea rtaCandidate = null;
if (!(view instanceof RTextArea)) {
rtaCandidate = getFirstRTextAreaDescendant(view);
if (rtaCandidate==null) {
throw new IllegalArgumentException(
"view must be either an RTextArea or a JLayer wrapping one");
}
}
else {
rtaCandidate = (RTextArea)view;
}
super.setViewportView(view);
if (gutter!=null) {
gutter.setTextArea(rtaCandidate);
}
}
/**
* Returns the first descendant of a component that is an
* RTextArea. This is primarily here to support
* javax.swing.JLayers that wrap RTextAreas.
*
* @param comp The component to recursively look through.
* @return The first descendant text area, or null if none
* is found.
*/
private static final RTextArea getFirstRTextAreaDescendant(Component comp) {
Stack stack = new Stack();
stack.add(comp);
while (!stack.isEmpty()) {
Component current = stack.pop();
if (current instanceof RTextArea) {
return (RTextArea)current;
}
if (current instanceof Container) {
Container container = (Container)current;
stack.addAll(Arrays.asList(container.getComponents()));
}
}
return null;
}
}